//===-- lldb-vscode.cpp -----------------------------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

#include "VSCode.h"

#include <assert.h>
#include <limits.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#if defined(_WIN32)
// We need to #define NOMINMAX in order to skip `min()` and `max()` macro
// definitions that conflict with other system headers.
// We also need to #undef GetObject (which is defined to GetObjectW) because
// the JSON code we use also has methods named `GetObject()` and we conflict
// against these.
#define NOMINMAX
#include <windows.h>
#undef GetObject
#include <io.h>
#else
#include <netinet/in.h>
#include <sys/socket.h>
#include <unistd.h>
#endif

#include <algorithm>
#include <chrono>
#include <fstream>
#include <map>
#include <memory>
#include <mutex>
#include <set>
#include <sstream>
#include <thread>
#include <vector>

#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/ScopeExit.h"
#include "llvm/Option/Arg.h"
#include "llvm/Option/ArgList.h"
#include "llvm/Option/Option.h"
#include "llvm/Support/Errno.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/InitLLVM.h"
#include "llvm/Support/Path.h"
#include "llvm/Support/PrettyStackTrace.h"
#include "llvm/Support/raw_ostream.h"

#include "JSONUtils.h"
#include "LLDBUtils.h"

#if defined(_WIN32)
#ifndef PATH_MAX
#define PATH_MAX MAX_PATH
#endif
typedef int socklen_t;
constexpr const char *dev_null_path = "nul";

#else
constexpr const char *dev_null_path = "/dev/null";

#endif

using namespace lldb_vscode;

namespace {
enum ID {
  OPT_INVALID = 0, // This is not an option ID.
#define OPTION(PREFIX, NAME, ID, KIND, GROUP, ALIAS, ALIASARGS, FLAGS, PARAM,  \
               HELPTEXT, METAVAR, VALUES)                                      \
  OPT_##ID,
#include "Options.inc"
#undef OPTION
};

#define PREFIX(NAME, VALUE) const char *const NAME[] = VALUE;
#include "Options.inc"
#undef PREFIX

static const llvm::opt::OptTable::Info InfoTable[] = {
#define OPTION(PREFIX, NAME, ID, KIND, GROUP, ALIAS, ALIASARGS, FLAGS, PARAM,  \
               HELPTEXT, METAVAR, VALUES)                                      \
  {PREFIX,      NAME,      HELPTEXT,                                           \
   METAVAR,     OPT_##ID,  llvm::opt::Option::KIND##Class,                     \
   PARAM,       FLAGS,     OPT_##GROUP,                                        \
   OPT_##ALIAS, ALIASARGS, VALUES},
#include "Options.inc"
#undef OPTION
};
class LLDBVSCodeOptTable : public llvm::opt::OptTable {
public:
  LLDBVSCodeOptTable() : OptTable(InfoTable, true) {}
};

typedef void (*RequestCallback)(const llvm::json::Object &command);

enum LaunchMethod { Launch, Attach, AttachForSuspendedLaunch };

SOCKET AcceptConnection(int portno) {
  // Accept a socket connection from any host on "portno".
  SOCKET newsockfd = -1;
  struct sockaddr_in serv_addr, cli_addr;
  SOCKET sockfd = socket(AF_INET, SOCK_STREAM, 0);
  if (sockfd < 0) {
    if (g_vsc.log)
      *g_vsc.log << "error: opening socket (" << strerror(errno) << ")"
                 << std::endl;
  } else {
    memset((char *)&serv_addr, 0, sizeof(serv_addr));
    serv_addr.sin_family = AF_INET;
    // serv_addr.sin_addr.s_addr = htonl(INADDR_ANY);
    serv_addr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
    serv_addr.sin_port = htons(portno);
    if (bind(sockfd, (struct sockaddr *)&serv_addr, sizeof(serv_addr)) < 0) {
      if (g_vsc.log)
        *g_vsc.log << "error: binding socket (" << strerror(errno) << ")"
                   << std::endl;
    } else {
      listen(sockfd, 5);
      socklen_t clilen = sizeof(cli_addr);
      newsockfd =
          llvm::sys::RetryAfterSignal(static_cast<SOCKET>(-1), accept, sockfd,
                                      (struct sockaddr *)&cli_addr, &clilen);
      if (newsockfd < 0)
        if (g_vsc.log)
          *g_vsc.log << "error: accept (" << strerror(errno) << ")"
                     << std::endl;
    }
#if defined(_WIN32)
    closesocket(sockfd);
#else
    close(sockfd);
#endif
  }
  return newsockfd;
}

std::vector<const char *> MakeArgv(const llvm::ArrayRef<std::string> &strs) {
  // Create and return an array of "const char *", one for each C string in
  // "strs" and terminate the list with a NULL. This can be used for argument
  // vectors (argv) or environment vectors (envp) like those passed to the
  // "main" function in C programs.
  std::vector<const char *> argv;
  for (const auto &s : strs)
    argv.push_back(s.c_str());
  argv.push_back(nullptr);
  return argv;
}

// Send a "exited" event to indicate the process has exited.
void SendProcessExitedEvent(lldb::SBProcess &process) {
  llvm::json::Object event(CreateEventObject("exited"));
  llvm::json::Object body;
  body.try_emplace("exitCode", (int64_t)process.GetExitStatus());
  event.try_emplace("body", std::move(body));
  g_vsc.SendJSON(llvm::json::Value(std::move(event)));
}

void SendThreadExitedEvent(lldb::tid_t tid) {
  llvm::json::Object event(CreateEventObject("thread"));
  llvm::json::Object body;
  body.try_emplace("reason", "exited");
  body.try_emplace("threadId", (int64_t)tid);
  event.try_emplace("body", std::move(body));
  g_vsc.SendJSON(llvm::json::Value(std::move(event)));
}

// Send a "terminated" event to indicate the process is done being
// debugged.
void SendTerminatedEvent() {
  if (!g_vsc.sent_terminated_event) {
    g_vsc.sent_terminated_event = true;
    g_vsc.RunTerminateCommands();
    // Send a "terminated" event
    llvm::json::Object event(CreateEventObject("terminated"));
    g_vsc.SendJSON(llvm::json::Value(std::move(event)));
  }
}

// Send a thread stopped event for all threads as long as the process
// is stopped.
void SendThreadStoppedEvent() {
  lldb::SBProcess process = g_vsc.target.GetProcess();
  if (process.IsValid()) {
    auto state = process.GetState();
    if (state == lldb::eStateStopped) {
      llvm::DenseSet<lldb::tid_t> old_thread_ids;
      old_thread_ids.swap(g_vsc.thread_ids);
      uint32_t stop_id = process.GetStopID();
      const uint32_t num_threads = process.GetNumThreads();

      // First make a pass through the threads to see if the focused thread
      // has a stop reason. In case the focus thread doesn't have a stop
      // reason, remember the first thread that has a stop reason so we can
      // set it as the focus thread if below if needed.
      lldb::tid_t first_tid_with_reason = LLDB_INVALID_THREAD_ID;
      uint32_t num_threads_with_reason = 0;
      for (uint32_t thread_idx = 0; thread_idx < num_threads; ++thread_idx) {
        lldb::SBThread thread = process.GetThreadAtIndex(thread_idx);
        const lldb::tid_t tid = thread.GetThreadID();
        const bool has_reason = ThreadHasStopReason(thread);
        // If the focus thread doesn't have a stop reason, clear the thread ID
        if (tid == g_vsc.focus_tid && !has_reason)
          g_vsc.focus_tid = LLDB_INVALID_THREAD_ID;
        if (has_reason) {
          ++num_threads_with_reason;
          if (first_tid_with_reason == LLDB_INVALID_THREAD_ID)
            first_tid_with_reason = tid;
        }
      }

      // We will have cleared g_vsc.focus_tid if he focus thread doesn't
      // have a stop reason, so if it was cleared, or wasn't set, then set the
      // focus thread to the first thread with a stop reason.
      if (g_vsc.focus_tid == LLDB_INVALID_THREAD_ID)
        g_vsc.focus_tid = first_tid_with_reason;

      // If no threads stopped with a reason, then report the first one so
      // we at least let the UI know we stopped.
      if (num_threads_with_reason == 0) {
        lldb::SBThread thread = process.GetThreadAtIndex(0);
        g_vsc.SendJSON(CreateThreadStopped(thread, stop_id));
      } else {
        for (uint32_t thread_idx = 0; thread_idx < num_threads; ++thread_idx) {
          lldb::SBThread thread = process.GetThreadAtIndex(thread_idx);
          g_vsc.thread_ids.insert(thread.GetThreadID());
          if (ThreadHasStopReason(thread)) {
            g_vsc.SendJSON(CreateThreadStopped(thread, stop_id));
          }
        }
      }

      for (auto tid : old_thread_ids) {
        auto end = g_vsc.thread_ids.end();
        auto pos = g_vsc.thread_ids.find(tid);
        if (pos == end)
          SendThreadExitedEvent(tid);
      }
    } else {
      if (g_vsc.log)
        *g_vsc.log << "error: SendThreadStoppedEvent() when process"
                      " isn't stopped ("
                   << lldb::SBDebugger::StateAsCString(state) << ')'
                   << std::endl;
    }
  } else {
    if (g_vsc.log)
      *g_vsc.log << "error: SendThreadStoppedEvent() invalid process"
                 << std::endl;
  }
  g_vsc.RunStopCommands();
}

// "ProcessEvent": {
//   "allOf": [
//     { "$ref": "#/definitions/Event" },
//     {
//       "type": "object",
//       "description": "Event message for 'process' event type. The event
//                       indicates that the debugger has begun debugging a
//                       new process. Either one that it has launched, or one
//                       that it has attached to.",
//       "properties": {
//         "event": {
//           "type": "string",
//           "enum": [ "process" ]
//         },
//         "body": {
//           "type": "object",
//           "properties": {
//             "name": {
//               "type": "string",
//               "description": "The logical name of the process. This is
//                               usually the full path to process's executable
//                               file. Example: /home/myproj/program.js."
//             },
//             "systemProcessId": {
//               "type": "integer",
//               "description": "The system process id of the debugged process.
//                               This property will be missing for non-system
//                               processes."
//             },
//             "isLocalProcess": {
//               "type": "boolean",
//               "description": "If true, the process is running on the same
//                               computer as the debug adapter."
//             },
//             "startMethod": {
//               "type": "string",
//               "enum": [ "launch", "attach", "attachForSuspendedLaunch" ],
//               "description": "Describes how the debug engine started
//                               debugging this process.",
//               "enumDescriptions": [
//                 "Process was launched under the debugger.",
//                 "Debugger attached to an existing process.",
//                 "A project launcher component has launched a new process in
//                  a suspended state and then asked the debugger to attach."
//               ]
//             }
//           },
//           "required": [ "name" ]
//         }
//       },
//       "required": [ "event", "body" ]
//     }
//   ]
// }
void SendProcessEvent(LaunchMethod launch_method) {
  lldb::SBFileSpec exe_fspec = g_vsc.target.GetExecutable();
  char exe_path[PATH_MAX];
  exe_fspec.GetPath(exe_path, sizeof(exe_path));
  llvm::json::Object event(CreateEventObject("process"));
  llvm::json::Object body;
  EmplaceSafeString(body, "name", std::string(exe_path));
  const auto pid = g_vsc.target.GetProcess().GetProcessID();
  body.try_emplace("systemProcessId", (int64_t)pid);
  body.try_emplace("isLocalProcess", true);
  const char *startMethod = nullptr;
  switch (launch_method) {
  case Launch:
    startMethod = "launch";
    break;
  case Attach:
    startMethod = "attach";
    break;
  case AttachForSuspendedLaunch:
    startMethod = "attachForSuspendedLaunch";
    break;
  }
  body.try_emplace("startMethod", startMethod);
  event.try_emplace("body", std::move(body));
  g_vsc.SendJSON(llvm::json::Value(std::move(event)));
}

// Grab any STDOUT and STDERR from the process and send it up to VS Code
// via an "output" event to the "stdout" and "stderr" categories.
void SendStdOutStdErr(lldb::SBProcess &process) {
  char buffer[1024];
  size_t count;
  while ((count = process.GetSTDOUT(buffer, sizeof(buffer))) > 0)
    g_vsc.SendOutput(OutputType::Stdout, llvm::StringRef(buffer, count));
  while ((count = process.GetSTDERR(buffer, sizeof(buffer))) > 0)
    g_vsc.SendOutput(OutputType::Stderr, llvm::StringRef(buffer, count));
}

void ProgressEventThreadFunction() {
  lldb::SBListener listener("lldb-vscode.progress.listener");
  g_vsc.debugger.GetBroadcaster().AddListener(
      listener, lldb::SBDebugger::eBroadcastBitProgress);
  g_vsc.broadcaster.AddListener(listener, eBroadcastBitStopProgressThread);
  lldb::SBEvent event;
  bool done = false;
  while (!done) {
    if (listener.WaitForEvent(1, event)) {
      const auto event_mask = event.GetType();
      if (event.BroadcasterMatchesRef(g_vsc.broadcaster)) {
        if (event_mask & eBroadcastBitStopProgressThread) {
          done = true;
        }
      } else {
        uint64_t progress_id = 0;
        uint64_t completed = 0;
        uint64_t total = 0;
        bool is_debugger_specific = false;
        const char *message = lldb::SBDebugger::GetProgressFromEvent(
            event, progress_id, completed, total, is_debugger_specific);
        if (message)
          g_vsc.SendProgressEvent(progress_id, message, completed, total);
      }
    }
  }
}

// All events from the debugger, target, process, thread and frames are
// received in this function that runs in its own thread. We are using a
// "FILE *" to output packets back to VS Code and they have mutexes in them
// them prevent multiple threads from writing simultaneously so no locking
// is required.
void EventThreadFunction() {
  lldb::SBEvent event;
  lldb::SBListener listener = g_vsc.debugger.GetListener();
  bool done = false;
  while (!done) {
    if (listener.WaitForEvent(1, event)) {
      const auto event_mask = event.GetType();
      if (lldb::SBProcess::EventIsProcessEvent(event)) {
        lldb::SBProcess process = lldb::SBProcess::GetProcessFromEvent(event);
        if (event_mask & lldb::SBProcess::eBroadcastBitStateChanged) {
          auto state = lldb::SBProcess::GetStateFromEvent(event);
          switch (state) {
          case lldb::eStateInvalid:
            // Not a state event
            break;
          case lldb::eStateUnloaded:
            break;
          case lldb::eStateConnected:
            break;
          case lldb::eStateAttaching:
            break;
          case lldb::eStateLaunching:
            break;
          case lldb::eStateStepping:
            break;
          case lldb::eStateCrashed:
            break;
          case lldb::eStateDetached:
            break;
          case lldb::eStateSuspended:
            break;
          case lldb::eStateStopped:
            // Only report a stopped event if the process was not restarted.
            if (!lldb::SBProcess::GetRestartedFromEvent(event)) {
              SendStdOutStdErr(process);
              SendThreadStoppedEvent();
            }
            break;
          case lldb::eStateRunning:
            break;
          case lldb::eStateExited: {
            // Run any exit LLDB commands the user specified in the
            // launch.json
            g_vsc.RunExitCommands();
            SendProcessExitedEvent(process);
            SendTerminatedEvent();
            done = true;
          } break;
          }
        } else if ((event_mask & lldb::SBProcess::eBroadcastBitSTDOUT) ||
                   (event_mask & lldb::SBProcess::eBroadcastBitSTDERR)) {
          SendStdOutStdErr(process);
        }
      } else if (lldb::SBBreakpoint::EventIsBreakpointEvent(event)) {
        if (event_mask & lldb::SBTarget::eBroadcastBitBreakpointChanged) {
          auto event_type =
              lldb::SBBreakpoint::GetBreakpointEventTypeFromEvent(event);
          auto bp = lldb::SBBreakpoint::GetBreakpointFromEvent(event);
          // If the breakpoint was originated from the IDE, it will have the
          // BreakpointBase::GetBreakpointLabel() label attached. Regardless
          // of wether the locations were added or removed, the breakpoint
          // ins't going away, so we the reason is always "changed".
          if ((event_type & lldb::eBreakpointEventTypeLocationsAdded ||
               event_type & lldb::eBreakpointEventTypeLocationsRemoved) &&
              bp.MatchesName(BreakpointBase::GetBreakpointLabel())) {
            auto bp_event = CreateEventObject("breakpoint");
            llvm::json::Object body;
            // As VSCode already knows the path of this breakpoint, we don't
            // need to send it back as part of a "changed" event. This
            // prevent us from sending to VSCode paths that should be source
            // mapped. Note that CreateBreakpoint doesn't apply source mapping.
            // Besides, the current implementation of VSCode ignores the
            // "source" element of breakpoint events.
            llvm::json::Value source_bp = CreateBreakpoint(bp);
            source_bp.getAsObject()->erase("source");

            body.try_emplace("breakpoint", source_bp);
            body.try_emplace("reason", "changed");
            bp_event.try_emplace("body", std::move(body));
            g_vsc.SendJSON(llvm::json::Value(std::move(bp_event)));
          }
        }
      } else if (event.BroadcasterMatchesRef(g_vsc.broadcaster)) {
        if (event_mask & eBroadcastBitStopEventThread) {
          done = true;
        }
      }
    }
  }
}

// Both attach and launch take a either a sourcePath or sourceMap
// argument (or neither), from which we need to set the target.source-map.
void SetSourceMapFromArguments(const llvm::json::Object &arguments) {
  const char *sourceMapHelp =
      "source must be be an array of two-element arrays, "
      "each containing a source and replacement path string.\n";

  std::string sourceMapCommand;
  llvm::raw_string_ostream strm(sourceMapCommand);
  strm << "settings set target.source-map ";
  auto sourcePath = GetString(arguments, "sourcePath");

  // sourceMap is the new, more general form of sourcePath and overrides it.
  auto sourceMap = arguments.getArray("sourceMap");
  if (sourceMap) {
    for (const auto &value : *sourceMap) {
      auto mapping = value.getAsArray();
      if (mapping == nullptr || mapping->size() != 2 ||
          (*mapping)[0].kind() != llvm::json::Value::String ||
          (*mapping)[1].kind() != llvm::json::Value::String) {
        g_vsc.SendOutput(OutputType::Console, llvm::StringRef(sourceMapHelp));
        return;
      }
      auto mapFrom = GetAsString((*mapping)[0]);
      auto mapTo = GetAsString((*mapping)[1]);
      strm << "\"" << mapFrom << "\" \"" << mapTo << "\" ";
    }
  } else {
    if (ObjectContainsKey(arguments, "sourceMap")) {
      g_vsc.SendOutput(OutputType::Console, llvm::StringRef(sourceMapHelp));
      return;
    }
    if (sourcePath.empty())
      return;
    // Do any source remapping needed before we create our targets
    strm << "\".\" \"" << sourcePath << "\"";
  }
  strm.flush();
  if (!sourceMapCommand.empty()) {
    g_vsc.RunLLDBCommands("Setting source map:", {sourceMapCommand});
  }
}

// "AttachRequest": {
//   "allOf": [ { "$ref": "#/definitions/Request" }, {
//     "type": "object",
//     "description": "Attach request; value of command field is 'attach'.",
//     "properties": {
//       "command": {
//         "type": "string",
//         "enum": [ "attach" ]
//       },
//       "arguments": {
//         "$ref": "#/definitions/AttachRequestArguments"
//       }
//     },
//     "required": [ "command", "arguments" ]
//   }]
// },
// "AttachRequestArguments": {
//   "type": "object",
//   "description": "Arguments for 'attach' request.\nThe attach request has no
//   standardized attributes."
// },
// "AttachResponse": {
//   "allOf": [ { "$ref": "#/definitions/Response" }, {
//     "type": "object",
//     "description": "Response to 'attach' request. This is just an
//     acknowledgement, so no body field is required."
//   }]
// }
void request_attach(const llvm::json::Object &request) {
  g_vsc.is_attach = true;
  llvm::json::Object response;
  lldb::SBError error;
  FillResponse(request, response);
  lldb::SBAttachInfo attach_info;
  auto arguments = request.getObject("arguments");
  const lldb::pid_t pid =
      GetUnsigned(arguments, "pid", LLDB_INVALID_PROCESS_ID);
  if (pid != LLDB_INVALID_PROCESS_ID)
    attach_info.SetProcessID(pid);
  const auto wait_for = GetBoolean(arguments, "waitFor", false);
  attach_info.SetWaitForLaunch(wait_for, false /*async*/);
  g_vsc.init_commands = GetStrings(arguments, "initCommands");
  g_vsc.pre_run_commands = GetStrings(arguments, "preRunCommands");
  g_vsc.stop_commands = GetStrings(arguments, "stopCommands");
  g_vsc.exit_commands = GetStrings(arguments, "exitCommands");
  g_vsc.terminate_commands = GetStrings(arguments, "terminateCommands");
  auto attachCommands = GetStrings(arguments, "attachCommands");
  llvm::StringRef core_file = GetString(arguments, "coreFile");
  g_vsc.stop_at_entry =
      core_file.empty() ? GetBoolean(arguments, "stopOnEntry", false) : true;
  const llvm::StringRef debuggerRoot = GetString(arguments, "debuggerRoot");

  // This is a hack for loading DWARF in .o files on Mac where the .o files
  // in the debug map of the main executable have relative paths which require
  // the lldb-vscode binary to have its working directory set to that relative
  // root for the .o files in order to be able to load debug info.
  if (!debuggerRoot.empty())
    llvm::sys::fs::set_current_path(debuggerRoot);

  // Run any initialize LLDB commands the user specified in the launch.json
  g_vsc.RunInitCommands();

  lldb::SBError status;
  g_vsc.SetTarget(g_vsc.CreateTargetFromArguments(*arguments, status));
  if (status.Fail()) {
    response["success"] = llvm::json::Value(false);
    EmplaceSafeString(response, "message", status.GetCString());
    g_vsc.SendJSON(llvm::json::Value(std::move(response)));
    return;
  }

  // Run any pre run LLDB commands the user specified in the launch.json
  g_vsc.RunPreRunCommands();

  if (pid == LLDB_INVALID_PROCESS_ID && wait_for) {
    char attach_msg[256];
    auto attach_msg_len = snprintf(attach_msg, sizeof(attach_msg),
                                   "Waiting to attach to \"%s\"...",
                                   g_vsc.target.GetExecutable().GetFilename());
    g_vsc.SendOutput(OutputType::Console,
                     llvm::StringRef(attach_msg, attach_msg_len));
  }
  if (attachCommands.empty()) {
    // No "attachCommands", just attach normally.
    // Disable async events so the attach will be successful when we return from
    // the launch call and the launch will happen synchronously
    g_vsc.debugger.SetAsync(false);
    if (core_file.empty())
      g_vsc.target.Attach(attach_info, error);
    else
      g_vsc.target.LoadCore(core_file.data(), error);
    // Reenable async events
    g_vsc.debugger.SetAsync(true);
  } else {
    // We have "attachCommands" that are a set of commands that are expected
    // to execute the commands after which a process should be created. If there
    // is no valid process after running these commands, we have failed.
    g_vsc.RunLLDBCommands("Running attachCommands:", attachCommands);
    // The custom commands might have created a new target so we should use the
    // selected target after these commands are run.
    g_vsc.target = g_vsc.debugger.GetSelectedTarget();
  }

  SetSourceMapFromArguments(*arguments);

  if (error.Success() && core_file.empty()) {
    auto attached_pid = g_vsc.target.GetProcess().GetProcessID();
    if (attached_pid == LLDB_INVALID_PROCESS_ID) {
      if (attachCommands.empty())
        error.SetErrorString("failed to attach to a process");
      else
        error.SetErrorString("attachCommands failed to attach to a process");
    }
  }

  if (error.Fail()) {
    response["success"] = llvm::json::Value(false);
    EmplaceSafeString(response, "message", std::string(error.GetCString()));
  }
  g_vsc.SendJSON(llvm::json::Value(std::move(response)));
  if (error.Success()) {
    SendProcessEvent(Attach);
    g_vsc.SendJSON(CreateEventObject("initialized"));
    // SendThreadStoppedEvent();
  }
}

// "ContinueRequest": {
//   "allOf": [ { "$ref": "#/definitions/Request" }, {
//     "type": "object",
//     "description": "Continue request; value of command field is 'continue'.
//                     The request starts the debuggee to run again.",
//     "properties": {
//       "command": {
//         "type": "string",
//         "enum": [ "continue" ]
//       },
//       "arguments": {
//         "$ref": "#/definitions/ContinueArguments"
//       }
//     },
//     "required": [ "command", "arguments"  ]
//   }]
// },
// "ContinueArguments": {
//   "type": "object",
//   "description": "Arguments for 'continue' request.",
//   "properties": {
//     "threadId": {
//       "type": "integer",
//       "description": "Continue execution for the specified thread (if
//                       possible). If the backend cannot continue on a single
//                       thread but will continue on all threads, it should
//                       set the allThreadsContinued attribute in the response
//                       to true."
//     }
//   },
//   "required": [ "threadId" ]
// },
// "ContinueResponse": {
//   "allOf": [ { "$ref": "#/definitions/Response" }, {
//     "type": "object",
//     "description": "Response to 'continue' request.",
//     "properties": {
//       "body": {
//         "type": "object",
//         "properties": {
//           "allThreadsContinued": {
//             "type": "boolean",
//             "description": "If true, the continue request has ignored the
//                             specified thread and continued all threads
//                             instead. If this attribute is missing a value
//                             of 'true' is assumed for backward
//                             compatibility."
//           }
//         }
//       }
//     },
//     "required": [ "body" ]
//   }]
// }
void request_continue(const llvm::json::Object &request) {
  llvm::json::Object response;
  FillResponse(request, response);
  lldb::SBProcess process = g_vsc.target.GetProcess();
  auto arguments = request.getObject("arguments");
  // Remember the thread ID that caused the resume so we can set the
  // "threadCausedFocus" boolean value in the "stopped" events.
  g_vsc.focus_tid = GetUnsigned(arguments, "threadId", LLDB_INVALID_THREAD_ID);
  lldb::SBError error = process.Continue();
  llvm::json::Object body;
  body.try_emplace("allThreadsContinued", true);
  response.try_emplace("body", std::move(body));
  g_vsc.SendJSON(llvm::json::Value(std::move(response)));
}

// "ConfigurationDoneRequest": {
//   "allOf": [ { "$ref": "#/definitions/Request" }, {
//             "type": "object",
//             "description": "ConfigurationDone request; value of command field
//             is 'configurationDone'.\nThe client of the debug protocol must
//             send this request at the end of the sequence of configuration
//             requests (which was started by the InitializedEvent).",
//             "properties": {
//             "command": {
//             "type": "string",
//             "enum": [ "configurationDone" ]
//             },
//             "arguments": {
//             "$ref": "#/definitions/ConfigurationDoneArguments"
//             }
//             },
//             "required": [ "command" ]
//             }]
// },
// "ConfigurationDoneArguments": {
//   "type": "object",
//   "description": "Arguments for 'configurationDone' request.\nThe
//   configurationDone request has no standardized attributes."
// },
// "ConfigurationDoneResponse": {
//   "allOf": [ { "$ref": "#/definitions/Response" }, {
//             "type": "object",
//             "description": "Response to 'configurationDone' request. This is
//             just an acknowledgement, so no body field is required."
//             }]
// },
void request_configurationDone(const llvm::json::Object &request) {
  llvm::json::Object response;
  FillResponse(request, response);
  g_vsc.SendJSON(llvm::json::Value(std::move(response)));
  if (g_vsc.stop_at_entry)
    SendThreadStoppedEvent();
  else
    g_vsc.target.GetProcess().Continue();
}

// "DisconnectRequest": {
//   "allOf": [ { "$ref": "#/definitions/Request" }, {
//     "type": "object",
//     "description": "Disconnect request; value of command field is
//                     'disconnect'.",
//     "properties": {
//       "command": {
//         "type": "string",
//         "enum": [ "disconnect" ]
//       },
//       "arguments": {
//         "$ref": "#/definitions/DisconnectArguments"
//       }
//     },
//     "required": [ "command" ]
//   }]
// },
// "DisconnectArguments": {
//   "type": "object",
//   "description": "Arguments for 'disconnect' request.",
//   "properties": {
//     "terminateDebuggee": {
//       "type": "boolean",
//       "description": "Indicates whether the debuggee should be terminated
//                       when the debugger is disconnected. If unspecified,
//                       the debug adapter is free to do whatever it thinks
//                       is best. A client can only rely on this attribute
//                       being properly honored if a debug adapter returns
//                       true for the 'supportTerminateDebuggee' capability."
//     },
//     "restart": {
//       "type": "boolean",
//       "description": "Indicates whether the debuggee should be restart
//                       the process."
//     }
//   }
// },
// "DisconnectResponse": {
//   "allOf": [ { "$ref": "#/definitions/Response" }, {
//     "type": "object",
//     "description": "Response to 'disconnect' request. This is just an
//                     acknowledgement, so no body field is required."
//   }]
// }
void request_disconnect(const llvm::json::Object &request) {
  llvm::json::Object response;
  FillResponse(request, response);
  auto arguments = request.getObject("arguments");

  bool defaultTerminateDebuggee = g_vsc.is_attach ? false : true;
  bool terminateDebuggee =
      GetBoolean(arguments, "terminateDebuggee", defaultTerminateDebuggee);
  lldb::SBProcess process = g_vsc.target.GetProcess();
  auto state = process.GetState();
  switch (state) {
  case lldb::eStateInvalid:
  case lldb::eStateUnloaded:
  case lldb::eStateDetached:
  case lldb::eStateExited:
    break;
  case lldb::eStateConnected:
  case lldb::eStateAttaching:
  case lldb::eStateLaunching:
  case lldb::eStateStepping:
  case lldb::eStateCrashed:
  case lldb::eStateSuspended:
  case lldb::eStateStopped:
  case lldb::eStateRunning:
    g_vsc.debugger.SetAsync(false);
    lldb::SBError error = terminateDebuggee ? process.Kill() : process.Detach();
    if (!error.Success())
      response.try_emplace("error", error.GetCString());
    g_vsc.debugger.SetAsync(true);
    break;
  }
  SendTerminatedEvent();
  g_vsc.SendJSON(llvm::json::Value(std::move(response)));
  if (g_vsc.event_thread.joinable()) {
    g_vsc.broadcaster.BroadcastEventByType(eBroadcastBitStopEventThread);
    g_vsc.event_thread.join();
  }
  if (g_vsc.progress_event_thread.joinable()) {
    g_vsc.broadcaster.BroadcastEventByType(eBroadcastBitStopProgressThread);
    g_vsc.progress_event_thread.join();
  }
}

void request_exceptionInfo(const llvm::json::Object &request) {
  llvm::json::Object response;
  FillResponse(request, response);
  auto arguments = request.getObject("arguments");
  llvm::json::Object body;
  lldb::SBThread thread = g_vsc.GetLLDBThread(*arguments);
  if (thread.IsValid()) {
    auto stopReason = thread.GetStopReason();
    if (stopReason == lldb::eStopReasonSignal)
      body.try_emplace("exceptionId", "signal");
    else if (stopReason == lldb::eStopReasonBreakpoint) {
      ExceptionBreakpoint *exc_bp = g_vsc.GetExceptionBPFromStopReason(thread);
      if (exc_bp) {
        EmplaceSafeString(body, "exceptionId", exc_bp->filter);
        EmplaceSafeString(body, "description", exc_bp->label);
      } else {
        body.try_emplace("exceptionId", "exception");
      }
    } else {
      body.try_emplace("exceptionId", "exception");
    }
    if (!ObjectContainsKey(body, "description")) {
      char description[1024];
      if (thread.GetStopDescription(description, sizeof(description))) {
        EmplaceSafeString(body, "description", std::string(description));
      }
    }
    body.try_emplace("breakMode", "always");
    // auto excInfoCount = thread.GetStopReasonDataCount();
    // for (auto i=0; i<excInfoCount; ++i) {
    //   uint64_t exc_data = thread.GetStopReasonDataAtIndex(i);
    // }
  } else {
    response["success"] = llvm::json::Value(false);
  }
  response.try_emplace("body", std::move(body));
  g_vsc.SendJSON(llvm::json::Value(std::move(response)));
}

// "CompletionsRequest": {
//   "allOf": [ { "$ref": "#/definitions/Request" }, {
//     "type": "object",
//     "description": "Returns a list of possible completions for a given caret
//     position and text.\nThe CompletionsRequest may only be called if the
//     'supportsCompletionsRequest' capability exists and is true.",
//     "properties": {
//       "command": {
//         "type": "string",
//         "enum": [ "completions" ]
//       },
//       "arguments": {
//         "$ref": "#/definitions/CompletionsArguments"
//       }
//     },
//     "required": [ "command", "arguments"  ]
//   }]
// },
// "CompletionsArguments": {
//   "type": "object",
//   "description": "Arguments for 'completions' request.",
//   "properties": {
//     "frameId": {
//       "type": "integer",
//       "description": "Returns completions in the scope of this stack frame.
//       If not specified, the completions are returned for the global scope."
//     },
//     "text": {
//       "type": "string",
//       "description": "One or more source lines. Typically this is the text a
//       user has typed into the debug console before he asked for completion."
//     },
//     "column": {
//       "type": "integer",
//       "description": "The character position for which to determine the
//       completion proposals."
//     },
//     "line": {
//       "type": "integer",
//       "description": "An optional line for which to determine the completion
//       proposals. If missing the first line of the text is assumed."
//     }
//   },
//   "required": [ "text", "column" ]
// },
// "CompletionsResponse": {
//   "allOf": [ { "$ref": "#/definitions/Response" }, {
//     "type": "object",
//     "description": "Response to 'completions' request.",
//     "properties": {
//       "body": {
//         "type": "object",
//         "properties": {
//           "targets": {
//             "type": "array",
//             "items": {
//               "$ref": "#/definitions/CompletionItem"
//             },
//             "description": "The possible completions for ."
//           }
//         },
//         "required": [ "targets" ]
//       }
//     },
//     "required": [ "body" ]
//   }]
// },
// "CompletionItem": {
//   "type": "object",
//   "description": "CompletionItems are the suggestions returned from the
//   CompletionsRequest.", "properties": {
//     "label": {
//       "type": "string",
//       "description": "The label of this completion item. By default this is
//       also the text that is inserted when selecting this completion."
//     },
//     "text": {
//       "type": "string",
//       "description": "If text is not falsy then it is inserted instead of the
//       label."
//     },
//     "sortText": {
//       "type": "string",
//       "description": "A string that should be used when comparing this item
//       with other items. When `falsy` the label is used."
//     },
//     "type": {
//       "$ref": "#/definitions/CompletionItemType",
//       "description": "The item's type. Typically the client uses this
//       information to render the item in the UI with an icon."
//     },
//     "start": {
//       "type": "integer",
//       "description": "This value determines the location (in the
//       CompletionsRequest's 'text' attribute) where the completion text is
//       added.\nIf missing the text is added at the location specified by the
//       CompletionsRequest's 'column' attribute."
//     },
//     "length": {
//       "type": "integer",
//       "description": "This value determines how many characters are
//       overwritten by the completion text.\nIf missing the value 0 is assumed
//       which results in the completion text being inserted."
//     }
//   },
//   "required": [ "label" ]
// },
// "CompletionItemType": {
//   "type": "string",
//   "description": "Some predefined types for the CompletionItem. Please note
//   that not all clients have specific icons for all of them.", "enum": [
//   "method", "function", "constructor", "field", "variable", "class",
//   "interface", "module", "property", "unit", "value", "enum", "keyword",
//   "snippet", "text", "color", "file", "reference", "customcolor" ]
// }
void request_completions(const llvm::json::Object &request) {
  llvm::json::Object response;
  FillResponse(request, response);
  llvm::json::Object body;
  auto arguments = request.getObject("arguments");
  std::string text = std::string(GetString(arguments, "text"));
  auto original_column = GetSigned(arguments, "column", text.size());
  auto actual_column = original_column - 1;
  llvm::json::Array targets;
  // NOTE: the 'line' argument is not needed, as multiline expressions
  // work well already
  // TODO: support frameID. Currently
  // g_vsc.debugger.GetCommandInterpreter().HandleCompletionWithDescriptions
  // is frame-unaware.

  if (!text.empty() && text[0] == '`') {
    text = text.substr(1);
    actual_column--;
  } else {
    text = "p " + text;
    actual_column += 2;
  }
  lldb::SBStringList matches;
  lldb::SBStringList descriptions;
  g_vsc.debugger.GetCommandInterpreter().HandleCompletionWithDescriptions(
      text.c_str(), actual_column, 0, -1, matches, descriptions);
  size_t count = std::min((uint32_t)100, matches.GetSize());
  targets.reserve(count);
  for (size_t i = 0; i < count; i++) {
    std::string match = matches.GetStringAtIndex(i);
    std::string description = descriptions.GetStringAtIndex(i);

    llvm::json::Object item;

    llvm::StringRef match_ref = match;
    for (llvm::StringRef commit_point : {".", "->"}) {
      if (match_ref.contains(commit_point)) {
        match_ref = match_ref.rsplit(commit_point).second;
      }
    }
    EmplaceSafeString(item, "text", match_ref);

    if (description.empty())
      EmplaceSafeString(item, "label", match);
    else
      EmplaceSafeString(item, "label", match + " -- " + description);

    targets.emplace_back(std::move(item));
  }

  body.try_emplace("targets", std::move(targets));
  response.try_emplace("body", std::move(body));
  g_vsc.SendJSON(llvm::json::Value(std::move(response)));
}

//  "EvaluateRequest": {
//    "allOf": [ { "$ref": "#/definitions/Request" }, {
//      "type": "object",
//      "description": "Evaluate request; value of command field is 'evaluate'.
//                      Evaluates the given expression in the context of the
//                      top most stack frame. The expression has access to any
//                      variables and arguments that are in scope.",
//      "properties": {
//        "command": {
//          "type": "string",
//          "enum": [ "evaluate" ]
//        },
//        "arguments": {
//          "$ref": "#/definitions/EvaluateArguments"
//        }
//      },
//      "required": [ "command", "arguments"  ]
//    }]
//  },
//  "EvaluateArguments": {
//    "type": "object",
//    "description": "Arguments for 'evaluate' request.",
//    "properties": {
//      "expression": {
//        "type": "string",
//        "description": "The expression to evaluate."
//      },
//      "frameId": {
//        "type": "integer",
//        "description": "Evaluate the expression in the scope of this stack
//                        frame. If not specified, the expression is evaluated
//                        in the global scope."
//      },
//      "context": {
//        "type": "string",
//        "_enum": [ "watch", "repl", "hover" ],
//        "enumDescriptions": [
//          "evaluate is run in a watch.",
//          "evaluate is run from REPL console.",
//          "evaluate is run from a data hover."
//        ],
//        "description": "The context in which the evaluate request is run."
//      },
//      "format": {
//        "$ref": "#/definitions/ValueFormat",
//        "description": "Specifies details on how to format the Evaluate
//                        result."
//      }
//    },
//    "required": [ "expression" ]
//  },
//  "EvaluateResponse": {
//    "allOf": [ { "$ref": "#/definitions/Response" }, {
//      "type": "object",
//      "description": "Response to 'evaluate' request.",
//      "properties": {
//        "body": {
//          "type": "object",
//          "properties": {
//            "result": {
//              "type": "string",
//              "description": "The result of the evaluate request."
//            },
//            "type": {
//              "type": "string",
//              "description": "The optional type of the evaluate result."
//            },
//            "presentationHint": {
//              "$ref": "#/definitions/VariablePresentationHint",
//              "description": "Properties of a evaluate result that can be
//                              used to determine how to render the result in
//                              the UI."
//            },
//            "variablesReference": {
//              "type": "number",
//              "description": "If variablesReference is > 0, the evaluate
//                              result is structured and its children can be
//                              retrieved by passing variablesReference to the
//                              VariablesRequest."
//            },
//            "namedVariables": {
//              "type": "number",
//              "description": "The number of named child variables. The
//                              client can use this optional information to
//                              present the variables in a paged UI and fetch
//                              them in chunks."
//            },
//            "indexedVariables": {
//              "type": "number",
//              "description": "The number of indexed child variables. The
//                              client can use this optional information to
//                              present the variables in a paged UI and fetch
//                              them in chunks."
//            }
//          },
//          "required": [ "result", "variablesReference" ]
//        }
//      },
//      "required": [ "body" ]
//    }]
//  }
void request_evaluate(const llvm::json::Object &request) {
  llvm::json::Object response;
  FillResponse(request, response);
  llvm::json::Object body;
  auto arguments = request.getObject("arguments");
  lldb::SBFrame frame = g_vsc.GetLLDBFrame(*arguments);
  const auto expression = GetString(arguments, "expression");
  llvm::StringRef context = GetString(arguments, "context");

  if (!expression.empty() && expression[0] == '`') {
    auto result =
        RunLLDBCommands(llvm::StringRef(), {std::string(expression.substr(1))});
    EmplaceSafeString(body, "result", result);
    body.try_emplace("variablesReference", (int64_t)0);
  } else {
    // Always try to get the answer from the local variables if possible. If
    // this fails, then if the context is not "hover", actually evaluate an
    // expression using the expression parser.
    //
    // "frame variable" is more reliable than the expression parser in
    // many cases and it is faster.
    lldb::SBValue value = frame.GetValueForVariablePath(
        expression.data(), lldb::eDynamicDontRunTarget);

    if (value.GetError().Fail() && context != "hover")
      value = frame.EvaluateExpression(expression.data());

    if (value.GetError().Fail()) {
      response["success"] = llvm::json::Value(false);
      // This error object must live until we're done with the pointer returned
      // by GetCString().
      lldb::SBError error = value.GetError();
      const char *error_cstr = error.GetCString();
      if (error_cstr && error_cstr[0])
        EmplaceSafeString(response, "message", std::string(error_cstr));
      else
        EmplaceSafeString(response, "message", "evaluate failed");
    } else {
      SetValueForKey(value, body, "result");
      auto value_typename = value.GetType().GetDisplayTypeName();
      EmplaceSafeString(body, "type",
                        value_typename ? value_typename : NO_TYPENAME);
      if (value.MightHaveChildren()) {
        auto variablesReference = VARIDX_TO_VARREF(g_vsc.variables.GetSize());
        g_vsc.variables.Append(value);
        body.try_emplace("variablesReference", variablesReference);
      } else {
        body.try_emplace("variablesReference", (int64_t)0);
      }
    }
  }
  response.try_emplace("body", std::move(body));
  g_vsc.SendJSON(llvm::json::Value(std::move(response)));
}

// "compileUnitsRequest": {
//   "allOf": [ { "$ref": "#/definitions/Request" }, {
//     "type": "object",
//     "description": "Compile Unit request; value of command field is
//                     'compileUnits'.",
//     "properties": {
//       "command": {
//         "type": "string",
//         "enum": [ "compileUnits" ]
//       },
//       "arguments": {
//         "$ref": "#/definitions/compileUnitRequestArguments"
//       }
//     },
//     "required": [ "command", "arguments" ]
//   }]
// },
// "compileUnitsRequestArguments": {
//   "type": "object",
//   "description": "Arguments for 'compileUnits' request.",
//   "properties": {
//     "moduleId": {
//       "type": "string",
//       "description": "The ID of the module."
//     }
//   },
//   "required": [ "moduleId" ]
// },
// "compileUnitsResponse": {
//   "allOf": [ { "$ref": "#/definitions/Response" }, {
//     "type": "object",
//     "description": "Response to 'compileUnits' request.",
//     "properties": {
//       "body": {
//         "description": "Response to 'compileUnits' request. Array of
//                         paths of compile units."
//       }
//     }
//   }]
// }
void request_compileUnits(const llvm::json::Object &request) {
  llvm::json::Object response;
  FillResponse(request, response);
  llvm::json::Object body;
  llvm::json::Array units;
  auto arguments = request.getObject("arguments");
  std::string module_id = std::string(GetString(arguments, "moduleId"));
  int num_modules = g_vsc.target.GetNumModules();
  for (int i = 0; i < num_modules; i++) {
    auto curr_module = g_vsc.target.GetModuleAtIndex(i);
    if (module_id == curr_module.GetUUIDString()) {
      int num_units = curr_module.GetNumCompileUnits();
      for (int j = 0; j < num_units; j++) {
        auto curr_unit = curr_module.GetCompileUnitAtIndex(j);
        units.emplace_back(CreateCompileUnit(curr_unit));
      }
      body.try_emplace("compileUnits", std::move(units));
      break;
    }
  }
  response.try_emplace("body", std::move(body));
  g_vsc.SendJSON(llvm::json::Value(std::move(response)));
}

// "modulesRequest": {
//   "allOf": [ { "$ref": "#/definitions/Request" }, {
//     "type": "object",
//     "description": "Modules request; value of command field is
//                     'modules'.",
//     "properties": {
//       "command": {
//         "type": "string",
//         "enum": [ "modules" ]
//       },
//     },
//     "required": [ "command" ]
//   }]
// },
// "modulesResponse": {
//   "allOf": [ { "$ref": "#/definitions/Response" }, {
//     "type": "object",
//     "description": "Response to 'modules' request.",
//     "properties": {
//       "body": {
//         "description": "Response to 'modules' request. Array of
//                         module objects."
//       }
//     }
//   }]
// }
void request_modules(const llvm::json::Object &request) {
  llvm::json::Object response;
  FillResponse(request, response);

  llvm::json::Array modules;
  for (size_t i = 0; i < g_vsc.target.GetNumModules(); i++) {
    lldb::SBModule module = g_vsc.target.GetModuleAtIndex(i);
    modules.emplace_back(CreateModule(module));
  }

  llvm::json::Object body;
  body.try_emplace("modules", std::move(modules));
  response.try_emplace("body", std::move(body));
  g_vsc.SendJSON(llvm::json::Value(std::move(response)));
}

// "InitializeRequest": {
//   "allOf": [ { "$ref": "#/definitions/Request" }, {
//     "type": "object",
//     "description": "Initialize request; value of command field is
//                     'initialize'.",
//     "properties": {
//       "command": {
//         "type": "string",
//         "enum": [ "initialize" ]
//       },
//       "arguments": {
//         "$ref": "#/definitions/InitializeRequestArguments"
//       }
//     },
//     "required": [ "command", "arguments" ]
//   }]
// },
// "InitializeRequestArguments": {
//   "type": "object",
//   "description": "Arguments for 'initialize' request.",
//   "properties": {
//     "clientID": {
//       "type": "string",
//       "description": "The ID of the (frontend) client using this adapter."
//     },
//     "adapterID": {
//       "type": "string",
//       "description": "The ID of the debug adapter."
//     },
//     "locale": {
//       "type": "string",
//       "description": "The ISO-639 locale of the (frontend) client using
//                       this adapter, e.g. en-US or de-CH."
//     },
//     "linesStartAt1": {
//       "type": "boolean",
//       "description": "If true all line numbers are 1-based (default)."
//     },
//     "columnsStartAt1": {
//       "type": "boolean",
//       "description": "If true all column numbers are 1-based (default)."
//     },
//     "pathFormat": {
//       "type": "string",
//       "_enum": [ "path", "uri" ],
//       "description": "Determines in what format paths are specified. The
//                       default is 'path', which is the native format."
//     },
//     "supportsVariableType": {
//       "type": "boolean",
//       "description": "Client supports the optional type attribute for
//                       variables."
//     },
//     "supportsVariablePaging": {
//       "type": "boolean",
//       "description": "Client supports the paging of variables."
//     },
//     "supportsRunInTerminalRequest": {
//       "type": "boolean",
//       "description": "Client supports the runInTerminal request."
//     }
//   },
//   "required": [ "adapterID" ]
// },
// "InitializeResponse": {
//   "allOf": [ { "$ref": "#/definitions/Response" }, {
//     "type": "object",
//     "description": "Response to 'initialize' request.",
//     "properties": {
//       "body": {
//         "$ref": "#/definitions/Capabilities",
//         "description": "The capabilities of this debug adapter."
//       }
//     }
//   }]
// }
void request_initialize(const llvm::json::Object &request) {
  g_vsc.debugger = lldb::SBDebugger::Create(true /*source_init_files*/);
  g_vsc.progress_event_thread = std::thread(ProgressEventThreadFunction);

  // Create an empty target right away since we might get breakpoint requests
  // before we are given an executable to launch in a "launch" request, or a
  // executable when attaching to a process by process ID in a "attach"
  // request.
  FILE *out = llvm::sys::RetryAfterSignal(nullptr, fopen, dev_null_path, "w");
  if (out) {
    // Set the output and error file handles to redirect into nothing otherwise
    // if any code in LLDB prints to the debugger file handles, the output and
    // error file handles are initialized to STDOUT and STDERR and any output
    // will kill our debug session.
    g_vsc.debugger.SetOutputFileHandle(out, true);
    g_vsc.debugger.SetErrorFileHandle(out, false);
  }

  // Start our event thread so we can receive events from the debugger, target,
  // process and more.
  g_vsc.event_thread = std::thread(EventThreadFunction);

  llvm::json::Object response;
  FillResponse(request, response);
  llvm::json::Object body;
  // The debug adapter supports the configurationDoneRequest.
  body.try_emplace("supportsConfigurationDoneRequest", true);
  // The debug adapter supports function breakpoints.
  body.try_emplace("supportsFunctionBreakpoints", true);
  // The debug adapter supports conditional breakpoints.
  body.try_emplace("supportsConditionalBreakpoints", true);
  // The debug adapter supports breakpoints that break execution after a
  // specified number of hits.
  body.try_emplace("supportsHitConditionalBreakpoints", true);
  // The debug adapter supports a (side effect free) evaluate request for
  // data hovers.
  body.try_emplace("supportsEvaluateForHovers", true);
  // Available filters or options for the setExceptionBreakpoints request.
  llvm::json::Array filters;
  for (const auto &exc_bp : g_vsc.exception_breakpoints) {
    filters.emplace_back(CreateExceptionBreakpointFilter(exc_bp));
  }
  body.try_emplace("exceptionBreakpointFilters", std::move(filters));
  // The debug adapter supports launching a debugee in intergrated VSCode
  // terminal.
  body.try_emplace("supportsRunInTerminalRequest", true);
  // The debug adapter supports stepping back via the stepBack and
  // reverseContinue requests.
  body.try_emplace("supportsStepBack", false);
  // The debug adapter supports setting a variable to a value.
  body.try_emplace("supportsSetVariable", true);
  // The debug adapter supports restarting a frame.
  body.try_emplace("supportsRestartFrame", false);
  // The debug adapter supports the gotoTargetsRequest.
  body.try_emplace("supportsGotoTargetsRequest", false);
  // The debug adapter supports the stepInTargetsRequest.
  body.try_emplace("supportsStepInTargetsRequest", false);
  // We need to improve the current implementation of completions in order to
  // enable it again. For some context, this is how VSCode works:
  // - VSCode sends a completion request whenever chars are added, the user
  //   triggers completion manually via CTRL-space or similar mechanisms, but
  //   not when there's a deletion. Besides, VSCode doesn't let us know which
  //   of these events we are handling. What is more, the use can paste or cut
  //   sections of the text arbitrarily.
  //   https://github.com/microsoft/vscode/issues/89531 tracks part of the
  //   issue just mentioned.
  // This behavior causes many problems with the current way completion is
  // implemented in lldb-vscode, as these requests could be really expensive,
  // blocking the debugger, and there could be many concurrent requests unless
  // the user types very slowly... We need to address this specific issue, or
  // at least trigger completion only when the user explicitly wants it, which
  // is the behavior of LLDB CLI, that expects a TAB.
  body.try_emplace("supportsCompletionsRequest", false);
  // The debug adapter supports the modules request.
  body.try_emplace("supportsModulesRequest", false);
  // The set of additional module information exposed by the debug adapter.
  //   body.try_emplace("additionalModuleColumns"] = ColumnDescriptor
  // Checksum algorithms supported by the debug adapter.
  //   body.try_emplace("supportedChecksumAlgorithms"] = ChecksumAlgorithm
  // The debug adapter supports the RestartRequest. In this case a client
  // should not implement 'restart' by terminating and relaunching the adapter
  // but by calling the RestartRequest.
  body.try_emplace("supportsRestartRequest", false);
  // The debug adapter supports 'exceptionOptions' on the
  // setExceptionBreakpoints request.
  body.try_emplace("supportsExceptionOptions", true);
  // The debug adapter supports a 'format' attribute on the stackTraceRequest,
  // variablesRequest, and evaluateRequest.
  body.try_emplace("supportsValueFormattingOptions", true);
  // The debug adapter supports the exceptionInfo request.
  body.try_emplace("supportsExceptionInfoRequest", true);
  // The debug adapter supports the 'terminateDebuggee' attribute on the
  // 'disconnect' request.
  body.try_emplace("supportTerminateDebuggee", true);
  // The debug adapter supports the delayed loading of parts of the stack,
  // which requires that both the 'startFrame' and 'levels' arguments and the
  // 'totalFrames' result of the 'StackTrace' request are supported.
  body.try_emplace("supportsDelayedStackTraceLoading", true);
  // The debug adapter supports the 'loadedSources' request.
  body.try_emplace("supportsLoadedSourcesRequest", false);
  // The debug adapter supports sending progress reporting events.
  body.try_emplace("supportsProgressReporting", true);

  response.try_emplace("body", std::move(body));
  g_vsc.SendJSON(llvm::json::Value(std::move(response)));
}

llvm::Error request_runInTerminal(const llvm::json::Object &launch_request) {
  g_vsc.is_attach = true;
  lldb::SBAttachInfo attach_info;

  llvm::Expected<std::shared_ptr<FifoFile>> comm_file_or_err =
      CreateRunInTerminalCommFile();
  if (!comm_file_or_err)
    return comm_file_or_err.takeError();
  FifoFile &comm_file = *comm_file_or_err.get();

  RunInTerminalDebugAdapterCommChannel comm_channel(comm_file.m_path);

  llvm::json::Object reverse_request = CreateRunInTerminalReverseRequest(
      launch_request, g_vsc.debug_adaptor_path, comm_file.m_path);
  llvm::json::Object reverse_response;
  lldb_vscode::PacketStatus status =
      g_vsc.SendReverseRequest(reverse_request, reverse_response);
  if (status != lldb_vscode::PacketStatus::Success)
    return llvm::createStringError(llvm::inconvertibleErrorCode(),
                                   "Process cannot be launched by the IDE. %s",
                                   comm_channel.GetLauncherError().c_str());

  if (llvm::Expected<lldb::pid_t> pid = comm_channel.GetLauncherPid())
    attach_info.SetProcessID(*pid);
  else
    return pid.takeError();

  g_vsc.debugger.SetAsync(false);
  lldb::SBError error;
  g_vsc.target.Attach(attach_info, error);

  if (error.Fail())
    return llvm::createStringError(llvm::inconvertibleErrorCode(),
                                   "Failed to attach to the target process. %s",
                                   comm_channel.GetLauncherError().c_str());
  // This will notify the runInTerminal launcher that we attached.
  // We have to make this async, as the function won't return until the launcher
  // resumes and reads the data.
  std::future<lldb::SBError> did_attach_message_success =
      comm_channel.NotifyDidAttach();

  // We just attached to the runInTerminal launcher, which was waiting to be
  // attached. We now resume it, so it can receive the didAttach notification
  // and then perform the exec. Upon continuing, the debugger will stop the
  // process right in the middle of the exec. To the user, what we are doing is
  // transparent, as they will only be able to see the process since the exec,
  // completely unaware of the preparatory work.
  g_vsc.target.GetProcess().Continue();

  // Now that the actual target is just starting (i.e. exec was just invoked),
  // we return the debugger to its async state.
  g_vsc.debugger.SetAsync(true);

  // If sending the notification failed, the launcher should be dead by now and
  // the async didAttach notification should have an error message, so we
  // return it. Otherwise, everything was a success.
  did_attach_message_success.wait();
  error = did_attach_message_success.get();
  if (error.Success())
    return llvm::Error::success();
  return llvm::createStringError(llvm::inconvertibleErrorCode(),
                                 error.GetCString());
}

// "LaunchRequest": {
//   "allOf": [ { "$ref": "#/definitions/Request" }, {
//     "type": "object",
//     "description": "Launch request; value of command field is 'launch'.",
//     "properties": {
//       "command": {
//         "type": "string",
//         "enum": [ "launch" ]
//       },
//       "arguments": {
//         "$ref": "#/definitions/LaunchRequestArguments"
//       }
//     },
//     "required": [ "command", "arguments"  ]
//   }]
// },
// "LaunchRequestArguments": {
//   "type": "object",
//   "description": "Arguments for 'launch' request.",
//   "properties": {
//     "noDebug": {
//       "type": "boolean",
//       "description": "If noDebug is true the launch request should launch
//                       the program without enabling debugging."
//     }
//   }
// },
// "LaunchResponse": {
//   "allOf": [ { "$ref": "#/definitions/Response" }, {
//     "type": "object",
//     "description": "Response to 'launch' request. This is just an
//                     acknowledgement, so no body field is required."
//   }]
// }
void request_launch(const llvm::json::Object &request) {
  g_vsc.is_attach = false;
  llvm::json::Object response;
  lldb::SBError error;
  FillResponse(request, response);
  auto arguments = request.getObject("arguments");
  g_vsc.init_commands = GetStrings(arguments, "initCommands");
  g_vsc.pre_run_commands = GetStrings(arguments, "preRunCommands");
  g_vsc.stop_commands = GetStrings(arguments, "stopCommands");
  g_vsc.exit_commands = GetStrings(arguments, "exitCommands");
  g_vsc.terminate_commands = GetStrings(arguments, "terminateCommands");
  auto launchCommands = GetStrings(arguments, "launchCommands");
  g_vsc.stop_at_entry = GetBoolean(arguments, "stopOnEntry", false);
  const llvm::StringRef debuggerRoot = GetString(arguments, "debuggerRoot");

  // This is a hack for loading DWARF in .o files on Mac where the .o files
  // in the debug map of the main executable have relative paths which require
  // the lldb-vscode binary to have its working directory set to that relative
  // root for the .o files in order to be able to load debug info.
  if (!debuggerRoot.empty())
    llvm::sys::fs::set_current_path(debuggerRoot);

  // Run any initialize LLDB commands the user specified in the launch.json.
  // This is run before target is created, so commands can't do anything with
  // the targets - preRunCommands are run with the target.
  g_vsc.RunInitCommands();

  SetSourceMapFromArguments(*arguments);

  lldb::SBError status;
  g_vsc.SetTarget(g_vsc.CreateTargetFromArguments(*arguments, status));
  if (status.Fail()) {
    response["success"] = llvm::json::Value(false);
    EmplaceSafeString(response, "message", status.GetCString());
    g_vsc.SendJSON(llvm::json::Value(std::move(response)));
    return;
  }

  // Instantiate a launch info instance for the target.
  auto launch_info = g_vsc.target.GetLaunchInfo();

  // Grab the current working directory if there is one and set it in the
  // launch info.
  const auto cwd = GetString(arguments, "cwd");
  if (!cwd.empty())
    launch_info.SetWorkingDirectory(cwd.data());

  // Extract any extra arguments and append them to our program arguments for
  // when we launch
  auto args = GetStrings(arguments, "args");
  if (!args.empty())
    launch_info.SetArguments(MakeArgv(args).data(), true);

  // Pass any environment variables along that the user specified.
  auto envs = GetStrings(arguments, "env");
  if (!envs.empty())
    launch_info.SetEnvironmentEntries(MakeArgv(envs).data(), true);

  auto flags = launch_info.GetLaunchFlags();

  if (GetBoolean(arguments, "disableASLR", true))
    flags |= lldb::eLaunchFlagDisableASLR;
  if (GetBoolean(arguments, "disableSTDIO", false))
    flags |= lldb::eLaunchFlagDisableSTDIO;
  if (GetBoolean(arguments, "shellExpandArguments", false))
    flags |= lldb::eLaunchFlagShellExpandArguments;
  const bool detatchOnError = GetBoolean(arguments, "detachOnError", false);
  launch_info.SetDetachOnError(detatchOnError);
  launch_info.SetLaunchFlags(flags | lldb::eLaunchFlagDebug |
                             lldb::eLaunchFlagStopAtEntry);

  // Run any pre run LLDB commands the user specified in the launch.json
  g_vsc.RunPreRunCommands();

  if (GetBoolean(arguments, "runInTerminal", false)) {
    if (llvm::Error err = request_runInTerminal(request))
      error.SetErrorString(llvm::toString(std::move(err)).c_str());
  } else if (launchCommands.empty()) {
    // Disable async events so the launch will be successful when we return from
    // the launch call and the launch will happen synchronously
    g_vsc.debugger.SetAsync(false);
    g_vsc.target.Launch(launch_info, error);
    g_vsc.debugger.SetAsync(true);
  } else {
    g_vsc.RunLLDBCommands("Running launchCommands:", launchCommands);
    // The custom commands might have created a new target so we should use the
    // selected target after these commands are run.
    g_vsc.target = g_vsc.debugger.GetSelectedTarget();
  }

  if (error.Fail()) {
    response["success"] = llvm::json::Value(false);
    EmplaceSafeString(response, "message", std::string(error.GetCString()));
  }
  g_vsc.SendJSON(llvm::json::Value(std::move(response)));

  if (g_vsc.is_attach)
    SendProcessEvent(Attach); // this happens when doing runInTerminal
  else
    SendProcessEvent(Launch);
  g_vsc.SendJSON(llvm::json::Value(CreateEventObject("initialized")));
}

// "NextRequest": {
//   "allOf": [ { "$ref": "#/definitions/Request" }, {
//     "type": "object",
//     "description": "Next request; value of command field is 'next'. The
//                     request starts the debuggee to run again for one step.
//                     The debug adapter first sends the NextResponse and then
//                     a StoppedEvent (event type 'step') after the step has
//                     completed.",
//     "properties": {
//       "command": {
//         "type": "string",
//         "enum": [ "next" ]
//       },
//       "arguments": {
//         "$ref": "#/definitions/NextArguments"
//       }
//     },
//     "required": [ "command", "arguments"  ]
//   }]
// },
// "NextArguments": {
//   "type": "object",
//   "description": "Arguments for 'next' request.",
//   "properties": {
//     "threadId": {
//       "type": "integer",
//       "description": "Execute 'next' for this thread."
//     }
//   },
//   "required": [ "threadId" ]
// },
// "NextResponse": {
//   "allOf": [ { "$ref": "#/definitions/Response" }, {
//     "type": "object",
//     "description": "Response to 'next' request. This is just an
//                     acknowledgement, so no body field is required."
//   }]
// }
void request_next(const llvm::json::Object &request) {
  llvm::json::Object response;
  FillResponse(request, response);
  auto arguments = request.getObject("arguments");
  lldb::SBThread thread = g_vsc.GetLLDBThread(*arguments);
  if (thread.IsValid()) {
    // Remember the thread ID that caused the resume so we can set the
    // "threadCausedFocus" boolean value in the "stopped" events.
    g_vsc.focus_tid = thread.GetThreadID();
    thread.StepOver();
  } else {
    response["success"] = llvm::json::Value(false);
  }
  g_vsc.SendJSON(llvm::json::Value(std::move(response)));
}

// "PauseRequest": {
//   "allOf": [ { "$ref": "#/definitions/Request" }, {
//     "type": "object",
//     "description": "Pause request; value of command field is 'pause'. The
//     request suspenses the debuggee. The debug adapter first sends the
//     PauseResponse and then a StoppedEvent (event type 'pause') after the
//     thread has been paused successfully.", "properties": {
//       "command": {
//         "type": "string",
//         "enum": [ "pause" ]
//       },
//       "arguments": {
//         "$ref": "#/definitions/PauseArguments"
//       }
//     },
//     "required": [ "command", "arguments"  ]
//   }]
// },
// "PauseArguments": {
//   "type": "object",
//   "description": "Arguments for 'pause' request.",
//   "properties": {
//     "threadId": {
//       "type": "integer",
//       "description": "Pause execution for this thread."
//     }
//   },
//   "required": [ "threadId" ]
// },
// "PauseResponse": {
//   "allOf": [ { "$ref": "#/definitions/Response" }, {
//     "type": "object",
//     "description": "Response to 'pause' request. This is just an
//     acknowledgement, so no body field is required."
//   }]
// }
void request_pause(const llvm::json::Object &request) {
  llvm::json::Object response;
  FillResponse(request, response);
  lldb::SBProcess process = g_vsc.target.GetProcess();
  lldb::SBError error = process.Stop();
  g_vsc.SendJSON(llvm::json::Value(std::move(response)));
}

// "ScopesRequest": {
//   "allOf": [ { "$ref": "#/definitions/Request" }, {
//     "type": "object",
//     "description": "Scopes request; value of command field is 'scopes'. The
//     request returns the variable scopes for a given stackframe ID.",
//     "properties": {
//       "command": {
//         "type": "string",
//         "enum": [ "scopes" ]
//       },
//       "arguments": {
//         "$ref": "#/definitions/ScopesArguments"
//       }
//     },
//     "required": [ "command", "arguments"  ]
//   }]
// },
// "ScopesArguments": {
//   "type": "object",
//   "description": "Arguments for 'scopes' request.",
//   "properties": {
//     "frameId": {
//       "type": "integer",
//       "description": "Retrieve the scopes for this stackframe."
//     }
//   },
//   "required": [ "frameId" ]
// },
// "ScopesResponse": {
//   "allOf": [ { "$ref": "#/definitions/Response" }, {
//     "type": "object",
//     "description": "Response to 'scopes' request.",
//     "properties": {
//       "body": {
//         "type": "object",
//         "properties": {
//           "scopes": {
//             "type": "array",
//             "items": {
//               "$ref": "#/definitions/Scope"
//             },
//             "description": "The scopes of the stackframe. If the array has
//             length zero, there are no scopes available."
//           }
//         },
//         "required": [ "scopes" ]
//       }
//     },
//     "required": [ "body" ]
//   }]
// }
void request_scopes(const llvm::json::Object &request) {
  llvm::json::Object response;
  FillResponse(request, response);
  llvm::json::Object body;
  auto arguments = request.getObject("arguments");
  lldb::SBFrame frame = g_vsc.GetLLDBFrame(*arguments);
  // As the user selects different stack frames in the GUI, a "scopes" request
  // will be sent to the DAP. This is the only way we know that the user has
  // selected a frame in a thread. There are no other notifications that are
  // sent and VS code doesn't allow multiple frames to show variables
  // concurrently. If we select the thread and frame as the "scopes" requests
  // are sent, this allows users to type commands in the debugger console
  // with a backtick character to run lldb commands and these lldb commands
  // will now have the right context selected as they are run. If the user
  // types "`bt" into the debugger console and we had another thread selected
  // in the LLDB library, we would show the wrong thing to the user. If the
  // users switches threads with a lldb command like "`thread select 14", the
  // GUI will not update as there are no "event" notification packets that
  // allow us to change the currently selected thread or frame in the GUI that
  // I am aware of.
  if (frame.IsValid()) {
    frame.GetThread().GetProcess().SetSelectedThread(frame.GetThread());
    frame.GetThread().SetSelectedFrame(frame.GetFrameID());
  }
  g_vsc.variables.Clear();
  g_vsc.variables.Append(frame.GetVariables(true,   // arguments
                                            true,   // locals
                                            false,  // statics
                                            true)); // in_scope_only
  g_vsc.num_locals = g_vsc.variables.GetSize();
  g_vsc.variables.Append(frame.GetVariables(false,  // arguments
                                            false,  // locals
                                            true,   // statics
                                            true)); // in_scope_only
  g_vsc.num_globals = g_vsc.variables.GetSize() - (g_vsc.num_locals);
  g_vsc.variables.Append(frame.GetRegisters());
  g_vsc.num_regs =
      g_vsc.variables.GetSize() - (g_vsc.num_locals + g_vsc.num_globals);
  body.try_emplace("scopes", g_vsc.CreateTopLevelScopes());
  response.try_emplace("body", std::move(body));
  g_vsc.SendJSON(llvm::json::Value(std::move(response)));
}

// "SetBreakpointsRequest": {
//   "allOf": [ { "$ref": "#/definitions/Request" }, {
//     "type": "object",
//     "description": "SetBreakpoints request; value of command field is
//     'setBreakpoints'. Sets multiple breakpoints for a single source and
//     clears all previous breakpoints in that source. To clear all breakpoint
//     for a source, specify an empty array. When a breakpoint is hit, a
//     StoppedEvent (event type 'breakpoint') is generated.", "properties": {
//       "command": {
//         "type": "string",
//         "enum": [ "setBreakpoints" ]
//       },
//       "arguments": {
//         "$ref": "#/definitions/SetBreakpointsArguments"
//       }
//     },
//     "required": [ "command", "arguments"  ]
//   }]
// },
// "SetBreakpointsArguments": {
//   "type": "object",
//   "description": "Arguments for 'setBreakpoints' request.",
//   "properties": {
//     "source": {
//       "$ref": "#/definitions/Source",
//       "description": "The source location of the breakpoints; either
//       source.path or source.reference must be specified."
//     },
//     "breakpoints": {
//       "type": "array",
//       "items": {
//         "$ref": "#/definitions/SourceBreakpoint"
//       },
//       "description": "The code locations of the breakpoints."
//     },
//     "lines": {
//       "type": "array",
//       "items": {
//         "type": "integer"
//       },
//       "description": "Deprecated: The code locations of the breakpoints."
//     },
//     "sourceModified": {
//       "type": "boolean",
//       "description": "A value of true indicates that the underlying source
//       has been modified which results in new breakpoint locations."
//     }
//   },
//   "required": [ "source" ]
// },
// "SetBreakpointsResponse": {
//   "allOf": [ { "$ref": "#/definitions/Response" }, {
//     "type": "object",
//     "description": "Response to 'setBreakpoints' request. Returned is
//     information about each breakpoint created by this request. This includes
//     the actual code location and whether the breakpoint could be verified.
//     The breakpoints returned are in the same order as the elements of the
//     'breakpoints' (or the deprecated 'lines') in the
//     SetBreakpointsArguments.", "properties": {
//       "body": {
//         "type": "object",
//         "properties": {
//           "breakpoints": {
//             "type": "array",
//             "items": {
//               "$ref": "#/definitions/Breakpoint"
//             },
//             "description": "Information about the breakpoints. The array
//             elements are in the same order as the elements of the
//             'breakpoints' (or the deprecated 'lines') in the
//             SetBreakpointsArguments."
//           }
//         },
//         "required": [ "breakpoints" ]
//       }
//     },
//     "required": [ "body" ]
//   }]
// },
// "SourceBreakpoint": {
//   "type": "object",
//   "description": "Properties of a breakpoint or logpoint passed to the
//   setBreakpoints request.", "properties": {
//     "line": {
//       "type": "integer",
//       "description": "The source line of the breakpoint or logpoint."
//     },
//     "column": {
//       "type": "integer",
//       "description": "An optional source column of the breakpoint."
//     },
//     "condition": {
//       "type": "string",
//       "description": "An optional expression for conditional breakpoints."
//     },
//     "hitCondition": {
//       "type": "string",
//       "description": "An optional expression that controls how many hits of
//       the breakpoint are ignored. The backend is expected to interpret the
//       expression as needed."
//     },
//     "logMessage": {
//       "type": "string",
//       "description": "If this attribute exists and is non-empty, the backend
//       must not 'break' (stop) but log the message instead. Expressions within
//       {} are interpolated."
//     }
//   },
//   "required": [ "line" ]
// }
void request_setBreakpoints(const llvm::json::Object &request) {
  llvm::json::Object response;
  lldb::SBError error;
  FillResponse(request, response);
  auto arguments = request.getObject("arguments");
  auto source = arguments->getObject("source");
  const auto path = GetString(source, "path");
  auto breakpoints = arguments->getArray("breakpoints");
  llvm::json::Array response_breakpoints;

  // Decode the source breakpoint infos for this "setBreakpoints" request
  SourceBreakpointMap request_bps;
  // "breakpoints" may be unset, in which case we treat it the same as being set
  // to an empty array.
  if (breakpoints) {
    for (const auto &bp : *breakpoints) {
      auto bp_obj = bp.getAsObject();
      if (bp_obj) {
        SourceBreakpoint src_bp(*bp_obj);
        request_bps[src_bp.line] = src_bp;

        // We check if this breakpoint already exists to update it
        auto existing_source_bps = g_vsc.source_breakpoints.find(path);
        if (existing_source_bps != g_vsc.source_breakpoints.end()) {
          const auto &existing_bp =
              existing_source_bps->second.find(src_bp.line);
          if (existing_bp != existing_source_bps->second.end()) {
            existing_bp->second.UpdateBreakpoint(src_bp);
            AppendBreakpoint(existing_bp->second.bp, response_breakpoints, path,
                             src_bp.line);
            continue;
          }
        }
        // At this point the breakpoint is new
        src_bp.SetBreakpoint(path.data());
        AppendBreakpoint(src_bp.bp, response_breakpoints, path, src_bp.line);
        g_vsc.source_breakpoints[path][src_bp.line] = std::move(src_bp);
      }
    }
  }

  // Delete any breakpoints in this source file that aren't in the
  // request_bps set. There is no call to remove breakpoints other than
  // calling this function with a smaller or empty "breakpoints" list.
  auto old_src_bp_pos = g_vsc.source_breakpoints.find(path);
  if (old_src_bp_pos != g_vsc.source_breakpoints.end()) {
    for (auto &old_bp : old_src_bp_pos->second) {
      auto request_pos = request_bps.find(old_bp.first);
      if (request_pos == request_bps.end()) {
        // This breakpoint no longer exists in this source file, delete it
        g_vsc.target.BreakpointDelete(old_bp.second.bp.GetID());
        old_src_bp_pos->second.erase(old_bp.first);
      }
    }
  }

  llvm::json::Object body;
  body.try_emplace("breakpoints", std::move(response_breakpoints));
  response.try_emplace("body", std::move(body));
  g_vsc.SendJSON(llvm::json::Value(std::move(response)));
}

// "SetExceptionBreakpointsRequest": {
//   "allOf": [ { "$ref": "#/definitions/Request" }, {
//     "type": "object",
//     "description": "SetExceptionBreakpoints request; value of command field
//     is 'setExceptionBreakpoints'. The request configures the debuggers
//     response to thrown exceptions. If an exception is configured to break, a
//     StoppedEvent is fired (event type 'exception').", "properties": {
//       "command": {
//         "type": "string",
//         "enum": [ "setExceptionBreakpoints" ]
//       },
//       "arguments": {
//         "$ref": "#/definitions/SetExceptionBreakpointsArguments"
//       }
//     },
//     "required": [ "command", "arguments"  ]
//   }]
// },
// "SetExceptionBreakpointsArguments": {
//   "type": "object",
//   "description": "Arguments for 'setExceptionBreakpoints' request.",
//   "properties": {
//     "filters": {
//       "type": "array",
//       "items": {
//         "type": "string"
//       },
//       "description": "IDs of checked exception options. The set of IDs is
//       returned via the 'exceptionBreakpointFilters' capability."
//     },
//     "exceptionOptions": {
//       "type": "array",
//       "items": {
//         "$ref": "#/definitions/ExceptionOptions"
//       },
//       "description": "Configuration options for selected exceptions."
//     }
//   },
//   "required": [ "filters" ]
// },
// "SetExceptionBreakpointsResponse": {
//   "allOf": [ { "$ref": "#/definitions/Response" }, {
//     "type": "object",
//     "description": "Response to 'setExceptionBreakpoints' request. This is
//     just an acknowledgement, so no body field is required."
//   }]
// }
void request_setExceptionBreakpoints(const llvm::json::Object &request) {
  llvm::json::Object response;
  lldb::SBError error;
  FillResponse(request, response);
  auto arguments = request.getObject("arguments");
  auto filters = arguments->getArray("filters");
  // Keep a list of any exception breakpoint filter names that weren't set
  // so we can clear any exception breakpoints if needed.
  std::set<std::string> unset_filters;
  for (const auto &bp : g_vsc.exception_breakpoints)
    unset_filters.insert(bp.filter);

  for (const auto &value : *filters) {
    const auto filter = GetAsString(value);
    auto exc_bp = g_vsc.GetExceptionBreakpoint(std::string(filter));
    if (exc_bp) {
      exc_bp->SetBreakpoint();
      unset_filters.erase(std::string(filter));
    }
  }
  for (const auto &filter : unset_filters) {
    auto exc_bp = g_vsc.GetExceptionBreakpoint(filter);
    if (exc_bp)
      exc_bp->ClearBreakpoint();
  }
  g_vsc.SendJSON(llvm::json::Value(std::move(response)));
}

// "SetFunctionBreakpointsRequest": {
//   "allOf": [ { "$ref": "#/definitions/Request" }, {
//     "type": "object",
//     "description": "SetFunctionBreakpoints request; value of command field is
//     'setFunctionBreakpoints'. Sets multiple function breakpoints and clears
//     all previous function breakpoints. To clear all function breakpoint,
//     specify an empty array. When a function breakpoint is hit, a StoppedEvent
//     (event type 'function breakpoint') is generated.", "properties": {
//       "command": {
//         "type": "string",
//         "enum": [ "setFunctionBreakpoints" ]
//       },
//       "arguments": {
//         "$ref": "#/definitions/SetFunctionBreakpointsArguments"
//       }
//     },
//     "required": [ "command", "arguments"  ]
//   }]
// },
// "SetFunctionBreakpointsArguments": {
//   "type": "object",
//   "description": "Arguments for 'setFunctionBreakpoints' request.",
//   "properties": {
//     "breakpoints": {
//       "type": "array",
//       "items": {
//         "$ref": "#/definitions/FunctionBreakpoint"
//       },
//       "description": "The function names of the breakpoints."
//     }
//   },
//   "required": [ "breakpoints" ]
// },
// "FunctionBreakpoint": {
//   "type": "object",
//   "description": "Properties of a breakpoint passed to the
//   setFunctionBreakpoints request.", "properties": {
//     "name": {
//       "type": "string",
//       "description": "The name of the function."
//     },
//     "condition": {
//       "type": "string",
//       "description": "An optional expression for conditional breakpoints."
//     },
//     "hitCondition": {
//       "type": "string",
//       "description": "An optional expression that controls how many hits of
//       the breakpoint are ignored. The backend is expected to interpret the
//       expression as needed."
//     }
//   },
//   "required": [ "name" ]
// },
// "SetFunctionBreakpointsResponse": {
//   "allOf": [ { "$ref": "#/definitions/Response" }, {
//     "type": "object",
//     "description": "Response to 'setFunctionBreakpoints' request. Returned is
//     information about each breakpoint created by this request.",
//     "properties": {
//       "body": {
//         "type": "object",
//         "properties": {
//           "breakpoints": {
//             "type": "array",
//             "items": {
//               "$ref": "#/definitions/Breakpoint"
//             },
//             "description": "Information about the breakpoints. The array
//             elements correspond to the elements of the 'breakpoints' array."
//           }
//         },
//         "required": [ "breakpoints" ]
//       }
//     },
//     "required": [ "body" ]
//   }]
// }
void request_setFunctionBreakpoints(const llvm::json::Object &request) {
  llvm::json::Object response;
  lldb::SBError error;
  FillResponse(request, response);
  auto arguments = request.getObject("arguments");
  auto breakpoints = arguments->getArray("breakpoints");
  FunctionBreakpointMap request_bps;
  llvm::json::Array response_breakpoints;
  for (const auto &value : *breakpoints) {
    auto bp_obj = value.getAsObject();
    if (bp_obj == nullptr)
      continue;
    FunctionBreakpoint func_bp(*bp_obj);
    request_bps[func_bp.functionName] = std::move(func_bp);
  }

  std::vector<llvm::StringRef> remove_names;
  // Disable any function breakpoints that aren't in the request_bps.
  // There is no call to remove function breakpoints other than calling this
  // function with a smaller or empty "breakpoints" list.
  for (auto &pair : g_vsc.function_breakpoints) {
    auto request_pos = request_bps.find(pair.first());
    if (request_pos == request_bps.end()) {
      // This function breakpoint no longer exists delete it from LLDB
      g_vsc.target.BreakpointDelete(pair.second.bp.GetID());
      remove_names.push_back(pair.first());
    } else {
      // Update the existing breakpoint as any setting withing the function
      // breakpoint might have changed.
      pair.second.UpdateBreakpoint(request_pos->second);
      // Remove this breakpoint from the request breakpoints since we have
      // handled it here and we don't need to set a new breakpoint below.
      request_bps.erase(request_pos);
      // Add this breakpoint info to the response
      AppendBreakpoint(pair.second.bp, response_breakpoints);
    }
  }
  // Remove any breakpoints that are no longer in our list
  for (const auto &name : remove_names)
    g_vsc.function_breakpoints.erase(name);

  // Any breakpoints that are left in "request_bps" are breakpoints that
  // need to be set.
  for (auto &pair : request_bps) {
    pair.second.SetBreakpoint();
    // Add this breakpoint info to the response
    AppendBreakpoint(pair.second.bp, response_breakpoints);
    g_vsc.function_breakpoints[pair.first()] = std::move(pair.second);
  }

  llvm::json::Object body;
  body.try_emplace("breakpoints", std::move(response_breakpoints));
  response.try_emplace("body", std::move(body));
  g_vsc.SendJSON(llvm::json::Value(std::move(response)));
}

// "SourceRequest": {
//   "allOf": [ { "$ref": "#/definitions/Request" }, {
//     "type": "object",
//     "description": "Source request; value of command field is 'source'. The
//     request retrieves the source code for a given source reference.",
//     "properties": {
//       "command": {
//         "type": "string",
//         "enum": [ "source" ]
//       },
//       "arguments": {
//         "$ref": "#/definitions/SourceArguments"
//       }
//     },
//     "required": [ "command", "arguments"  ]
//   }]
// },
// "SourceArguments": {
//   "type": "object",
//   "description": "Arguments for 'source' request.",
//   "properties": {
//     "source": {
//       "$ref": "#/definitions/Source",
//       "description": "Specifies the source content to load. Either
//       source.path or source.sourceReference must be specified."
//     },
//     "sourceReference": {
//       "type": "integer",
//       "description": "The reference to the source. This is the same as
//       source.sourceReference. This is provided for backward compatibility
//       since old backends do not understand the 'source' attribute."
//     }
//   },
//   "required": [ "sourceReference" ]
// },
// "SourceResponse": {
//   "allOf": [ { "$ref": "#/definitions/Response" }, {
//     "type": "object",
//     "description": "Response to 'source' request.",
//     "properties": {
//       "body": {
//         "type": "object",
//         "properties": {
//           "content": {
//             "type": "string",
//             "description": "Content of the source reference."
//           },
//           "mimeType": {
//             "type": "string",
//             "description": "Optional content type (mime type) of the source."
//           }
//         },
//         "required": [ "content" ]
//       }
//     },
//     "required": [ "body" ]
//   }]
// }
void request_source(const llvm::json::Object &request) {
  llvm::json::Object response;
  FillResponse(request, response);
  llvm::json::Object body;

  auto arguments = request.getObject("arguments");
  auto source = arguments->getObject("source");
  auto sourceReference = GetSigned(source, "sourceReference", -1);
  auto pos = g_vsc.source_map.find((lldb::addr_t)sourceReference);
  if (pos != g_vsc.source_map.end()) {
    EmplaceSafeString(body, "content", pos->second.content);
  } else {
    response["success"] = llvm::json::Value(false);
  }
  EmplaceSafeString(body, "mimeType", "text/x-lldb.disassembly");
  response.try_emplace("body", std::move(body));
  g_vsc.SendJSON(llvm::json::Value(std::move(response)));
}

// "StackTraceRequest": {
//   "allOf": [ { "$ref": "#/definitions/Request" }, {
//     "type": "object",
//     "description": "StackTrace request; value of command field is
//     'stackTrace'. The request returns a stacktrace from the current execution
//     state.", "properties": {
//       "command": {
//         "type": "string",
//         "enum": [ "stackTrace" ]
//       },
//       "arguments": {
//         "$ref": "#/definitions/StackTraceArguments"
//       }
//     },
//     "required": [ "command", "arguments"  ]
//   }]
// },
// "StackTraceArguments": {
//   "type": "object",
//   "description": "Arguments for 'stackTrace' request.",
//   "properties": {
//     "threadId": {
//       "type": "integer",
//       "description": "Retrieve the stacktrace for this thread."
//     },
//     "startFrame": {
//       "type": "integer",
//       "description": "The index of the first frame to return; if omitted
//       frames start at 0."
//     },
//     "levels": {
//       "type": "integer",
//       "description": "The maximum number of frames to return. If levels is
//       not specified or 0, all frames are returned."
//     },
//     "format": {
//       "$ref": "#/definitions/StackFrameFormat",
//       "description": "Specifies details on how to format the stack frames."
//     }
//  },
//   "required": [ "threadId" ]
// },
// "StackTraceResponse": {
//   "allOf": [ { "$ref": "#/definitions/Response" }, {
//     "type": "object",
//     "description": "Response to 'stackTrace' request.",
//     "properties": {
//       "body": {
//         "type": "object",
//         "properties": {
//           "stackFrames": {
//             "type": "array",
//             "items": {
//               "$ref": "#/definitions/StackFrame"
//             },
//             "description": "The frames of the stackframe. If the array has
//             length zero, there are no stackframes available. This means that
//             there is no location information available."
//           },
//           "totalFrames": {
//             "type": "integer",
//             "description": "The total number of frames available."
//           }
//         },
//         "required": [ "stackFrames" ]
//       }
//     },
//     "required": [ "body" ]
//   }]
// }
void request_stackTrace(const llvm::json::Object &request) {
  llvm::json::Object response;
  FillResponse(request, response);
  lldb::SBError error;
  auto arguments = request.getObject("arguments");
  lldb::SBThread thread = g_vsc.GetLLDBThread(*arguments);
  llvm::json::Array stackFrames;
  llvm::json::Object body;

  if (thread.IsValid()) {
    const auto startFrame = GetUnsigned(arguments, "startFrame", 0);
    const auto levels = GetUnsigned(arguments, "levels", 0);
    const auto endFrame = (levels == 0) ? INT64_MAX : (startFrame + levels);
    for (uint32_t i = startFrame; i < endFrame; ++i) {
      auto frame = thread.GetFrameAtIndex(i);
      if (!frame.IsValid())
        break;
      stackFrames.emplace_back(CreateStackFrame(frame));
    }
    const auto totalFrames = thread.GetNumFrames();
    body.try_emplace("totalFrames", totalFrames);
  }
  body.try_emplace("stackFrames", std::move(stackFrames));
  response.try_emplace("body", std::move(body));
  g_vsc.SendJSON(llvm::json::Value(std::move(response)));
}

// "StepInRequest": {
//   "allOf": [ { "$ref": "#/definitions/Request" }, {
//     "type": "object",
//     "description": "StepIn request; value of command field is 'stepIn'. The
//     request starts the debuggee to step into a function/method if possible.
//     If it cannot step into a target, 'stepIn' behaves like 'next'. The debug
//     adapter first sends the StepInResponse and then a StoppedEvent (event
//     type 'step') after the step has completed. If there are multiple
//     function/method calls (or other targets) on the source line, the optional
//     argument 'targetId' can be used to control into which target the 'stepIn'
//     should occur. The list of possible targets for a given source line can be
//     retrieved via the 'stepInTargets' request.", "properties": {
//       "command": {
//         "type": "string",
//         "enum": [ "stepIn" ]
//       },
//       "arguments": {
//         "$ref": "#/definitions/StepInArguments"
//       }
//     },
//     "required": [ "command", "arguments"  ]
//   }]
// },
// "StepInArguments": {
//   "type": "object",
//   "description": "Arguments for 'stepIn' request.",
//   "properties": {
//     "threadId": {
//       "type": "integer",
//       "description": "Execute 'stepIn' for this thread."
//     },
//     "targetId": {
//       "type": "integer",
//       "description": "Optional id of the target to step into."
//     }
//   },
//   "required": [ "threadId" ]
// },
// "StepInResponse": {
//   "allOf": [ { "$ref": "#/definitions/Response" }, {
//     "type": "object",
//     "description": "Response to 'stepIn' request. This is just an
//     acknowledgement, so no body field is required."
//   }]
// }
void request_stepIn(const llvm::json::Object &request) {
  llvm::json::Object response;
  FillResponse(request, response);
  auto arguments = request.getObject("arguments");
  lldb::SBThread thread = g_vsc.GetLLDBThread(*arguments);
  if (thread.IsValid()) {
    // Remember the thread ID that caused the resume so we can set the
    // "threadCausedFocus" boolean value in the "stopped" events.
    g_vsc.focus_tid = thread.GetThreadID();
    thread.StepInto();
  } else {
    response["success"] = llvm::json::Value(false);
  }
  g_vsc.SendJSON(llvm::json::Value(std::move(response)));
}

// "StepOutRequest": {
//   "allOf": [ { "$ref": "#/definitions/Request" }, {
//     "type": "object",
//     "description": "StepOut request; value of command field is 'stepOut'. The
//     request starts the debuggee to run again for one step. The debug adapter
//     first sends the StepOutResponse and then a StoppedEvent (event type
//     'step') after the step has completed.", "properties": {
//       "command": {
//         "type": "string",
//         "enum": [ "stepOut" ]
//       },
//       "arguments": {
//         "$ref": "#/definitions/StepOutArguments"
//       }
//     },
//     "required": [ "command", "arguments"  ]
//   }]
// },
// "StepOutArguments": {
//   "type": "object",
//   "description": "Arguments for 'stepOut' request.",
//   "properties": {
//     "threadId": {
//       "type": "integer",
//       "description": "Execute 'stepOut' for this thread."
//     }
//   },
//   "required": [ "threadId" ]
// },
// "StepOutResponse": {
//   "allOf": [ { "$ref": "#/definitions/Response" }, {
//     "type": "object",
//     "description": "Response to 'stepOut' request. This is just an
//     acknowledgement, so no body field is required."
//   }]
// }
void request_stepOut(const llvm::json::Object &request) {
  llvm::json::Object response;
  FillResponse(request, response);
  auto arguments = request.getObject("arguments");
  lldb::SBThread thread = g_vsc.GetLLDBThread(*arguments);
  if (thread.IsValid()) {
    // Remember the thread ID that caused the resume so we can set the
    // "threadCausedFocus" boolean value in the "stopped" events.
    g_vsc.focus_tid = thread.GetThreadID();
    thread.StepOut();
  } else {
    response["success"] = llvm::json::Value(false);
  }
  g_vsc.SendJSON(llvm::json::Value(std::move(response)));
}

// "ThreadsRequest": {
//   "allOf": [ { "$ref": "#/definitions/Request" }, {
//     "type": "object",
//     "description": "Thread request; value of command field is 'threads'. The
//     request retrieves a list of all threads.", "properties": {
//       "command": {
//         "type": "string",
//         "enum": [ "threads" ]
//       }
//     },
//     "required": [ "command" ]
//   }]
// },
// "ThreadsResponse": {
//   "allOf": [ { "$ref": "#/definitions/Response" }, {
//     "type": "object",
//     "description": "Response to 'threads' request.",
//     "properties": {
//       "body": {
//         "type": "object",
//         "properties": {
//           "threads": {
//             "type": "array",
//             "items": {
//               "$ref": "#/definitions/Thread"
//             },
//             "description": "All threads."
//           }
//         },
//         "required": [ "threads" ]
//       }
//     },
//     "required": [ "body" ]
//   }]
// }
void request_threads(const llvm::json::Object &request) {

  lldb::SBProcess process = g_vsc.target.GetProcess();
  llvm::json::Object response;
  FillResponse(request, response);

  const uint32_t num_threads = process.GetNumThreads();
  llvm::json::Array threads;
  for (uint32_t thread_idx = 0; thread_idx < num_threads; ++thread_idx) {
    lldb::SBThread thread = process.GetThreadAtIndex(thread_idx);
    threads.emplace_back(CreateThread(thread));
  }
  if (threads.size() == 0) {
    response["success"] = llvm::json::Value(false);
  }
  llvm::json::Object body;
  body.try_emplace("threads", std::move(threads));
  response.try_emplace("body", std::move(body));
  g_vsc.SendJSON(llvm::json::Value(std::move(response)));
}

// "SetVariableRequest": {
//   "allOf": [ { "$ref": "#/definitions/Request" }, {
//     "type": "object",
//     "description": "setVariable request; value of command field is
//     'setVariable'. Set the variable with the given name in the variable
//     container to a new value.", "properties": {
//       "command": {
//         "type": "string",
//         "enum": [ "setVariable" ]
//       },
//       "arguments": {
//         "$ref": "#/definitions/SetVariableArguments"
//       }
//     },
//     "required": [ "command", "arguments"  ]
//   }]
// },
// "SetVariableArguments": {
//   "type": "object",
//   "description": "Arguments for 'setVariable' request.",
//   "properties": {
//     "variablesReference": {
//       "type": "integer",
//       "description": "The reference of the variable container."
//     },
//     "name": {
//       "type": "string",
//       "description": "The name of the variable."
//     },
//     "value": {
//       "type": "string",
//       "description": "The value of the variable."
//     },
//     "format": {
//       "$ref": "#/definitions/ValueFormat",
//       "description": "Specifies details on how to format the response value."
//     }
//   },
//   "required": [ "variablesReference", "name", "value" ]
// },
// "SetVariableResponse": {
//   "allOf": [ { "$ref": "#/definitions/Response" }, {
//     "type": "object",
//     "description": "Response to 'setVariable' request.",
//     "properties": {
//       "body": {
//         "type": "object",
//         "properties": {
//           "value": {
//             "type": "string",
//             "description": "The new value of the variable."
//           },
//           "type": {
//             "type": "string",
//             "description": "The type of the new value. Typically shown in the
//             UI when hovering over the value."
//           },
//           "variablesReference": {
//             "type": "number",
//             "description": "If variablesReference is > 0, the new value is
//             structured and its children can be retrieved by passing
//             variablesReference to the VariablesRequest."
//           },
//           "namedVariables": {
//             "type": "number",
//             "description": "The number of named child variables. The client
//             can use this optional information to present the variables in a
//             paged UI and fetch them in chunks."
//           },
//           "indexedVariables": {
//             "type": "number",
//             "description": "The number of indexed child variables. The client
//             can use this optional information to present the variables in a
//             paged UI and fetch them in chunks."
//           }
//         },
//         "required": [ "value" ]
//       }
//     },
//     "required": [ "body" ]
//   }]
// }
void request_setVariable(const llvm::json::Object &request) {
  llvm::json::Object response;
  FillResponse(request, response);
  llvm::json::Array variables;
  llvm::json::Object body;
  auto arguments = request.getObject("arguments");
  // This is a reference to the containing variable/scope
  const auto variablesReference =
      GetUnsigned(arguments, "variablesReference", 0);
  const auto name = GetString(arguments, "name");
  const auto value = GetString(arguments, "value");
  // Set success to false just in case we don't find the variable by name
  response.try_emplace("success", false);

  lldb::SBValue variable;
  int64_t newVariablesReference = 0;

  // The "id" is the unique integer ID that is unique within the enclosing
  // variablesReference. It is optionally added to any "interface Variable"
  // objects to uniquely identify a variable within an enclosing
  // variablesReference. It helps to disambiguate between two variables that
  // have the same name within the same scope since the "setVariables" request
  // only specifies the variable reference of the enclosing scope/variable, and
  // the name of the variable. We could have two shadowed variables with the
  // same name in "Locals" or "Globals". In our case the "id" absolute index
  // of the variable within the g_vsc.variables list.
  const auto id_value = GetUnsigned(arguments, "id", UINT64_MAX);
  if (id_value != UINT64_MAX) {
    variable = g_vsc.variables.GetValueAtIndex(id_value);
  } else if (VARREF_IS_SCOPE(variablesReference)) {
    // variablesReference is one of our scopes, not an actual variable it is
    // asking for a variable in locals or globals or registers
    int64_t start_idx = 0;
    int64_t end_idx = 0;
    switch (variablesReference) {
    case VARREF_LOCALS:
      start_idx = 0;
      end_idx = start_idx + g_vsc.num_locals;
      break;
    case VARREF_GLOBALS:
      start_idx = g_vsc.num_locals;
      end_idx = start_idx + g_vsc.num_globals;
      break;
    case VARREF_REGS:
      start_idx = g_vsc.num_locals + g_vsc.num_globals;
      end_idx = start_idx + g_vsc.num_regs;
      break;
    default:
      break;
    }

    // Find the variable by name in the correct scope and hope we don't have
    // multiple variables with the same name. We search backwards because
    // the list of variables has the top most variables first and variables
    // in deeper scopes are last. This means we will catch the deepest
    // variable whose name matches which is probably what the user wants.
    for (int64_t i = end_idx - 1; i >= start_idx; --i) {
      auto curr_variable = g_vsc.variables.GetValueAtIndex(i);
      llvm::StringRef variable_name(curr_variable.GetName());
      if (variable_name == name) {
        variable = curr_variable;
        if (curr_variable.MightHaveChildren())
          newVariablesReference = i;
        break;
      }
    }
  } else {
    // We have a named item within an actual variable so we need to find it
    // withing the container variable by name.
    const int64_t var_idx = VARREF_TO_VARIDX(variablesReference);
    lldb::SBValue container = g_vsc.variables.GetValueAtIndex(var_idx);
    variable = container.GetChildMemberWithName(name.data());
    if (!variable.IsValid()) {
      if (name.startswith("[")) {
        llvm::StringRef index_str(name.drop_front(1));
        uint64_t index = 0;
        if (!index_str.consumeInteger(0, index)) {
          if (index_str == "]")
            variable = container.GetChildAtIndex(index);
        }
      }
    }

    // We don't know the index of the variable in our g_vsc.variables
    if (variable.IsValid()) {
      if (variable.MightHaveChildren()) {
        newVariablesReference = VARIDX_TO_VARREF(g_vsc.variables.GetSize());
        g_vsc.variables.Append(variable);
      }
    }
  }

  if (variable.IsValid()) {
    lldb::SBError error;
    bool success = variable.SetValueFromCString(value.data(), error);
    if (success) {
      SetValueForKey(variable, body, "value");
      EmplaceSafeString(body, "type", variable.GetType().GetDisplayTypeName());
      body.try_emplace("variablesReference", newVariablesReference);
    } else {
      EmplaceSafeString(body, "message", std::string(error.GetCString()));
    }
    response["success"] = llvm::json::Value(success);
  }

  response.try_emplace("body", std::move(body));
  g_vsc.SendJSON(llvm::json::Value(std::move(response)));
}

// "VariablesRequest": {
//   "allOf": [ { "$ref": "#/definitions/Request" }, {
//     "type": "object",
//     "description": "Variables request; value of command field is 'variables'.
//     Retrieves all child variables for the given variable reference. An
//     optional filter can be used to limit the fetched children to either named
//     or indexed children.", "properties": {
//       "command": {
//         "type": "string",
//         "enum": [ "variables" ]
//       },
//       "arguments": {
//         "$ref": "#/definitions/VariablesArguments"
//       }
//     },
//     "required": [ "command", "arguments"  ]
//   }]
// },
// "VariablesArguments": {
//   "type": "object",
//   "description": "Arguments for 'variables' request.",
//   "properties": {
//     "variablesReference": {
//       "type": "integer",
//       "description": "The Variable reference."
//     },
//     "filter": {
//       "type": "string",
//       "enum": [ "indexed", "named" ],
//       "description": "Optional filter to limit the child variables to either
//       named or indexed. If ommited, both types are fetched."
//     },
//     "start": {
//       "type": "integer",
//       "description": "The index of the first variable to return; if omitted
//       children start at 0."
//     },
//     "count": {
//       "type": "integer",
//       "description": "The number of variables to return. If count is missing
//       or 0, all variables are returned."
//     },
//     "format": {
//       "$ref": "#/definitions/ValueFormat",
//       "description": "Specifies details on how to format the Variable
//       values."
//     }
//   },
//   "required": [ "variablesReference" ]
// },
// "VariablesResponse": {
//   "allOf": [ { "$ref": "#/definitions/Response" }, {
//     "type": "object",
//     "description": "Response to 'variables' request.",
//     "properties": {
//       "body": {
//         "type": "object",
//         "properties": {
//           "variables": {
//             "type": "array",
//             "items": {
//               "$ref": "#/definitions/Variable"
//             },
//             "description": "All (or a range) of variables for the given
//             variable reference."
//           }
//         },
//         "required": [ "variables" ]
//       }
//     },
//     "required": [ "body" ]
//   }]
// }
void request_variables(const llvm::json::Object &request) {
  llvm::json::Object response;
  FillResponse(request, response);
  llvm::json::Array variables;
  auto arguments = request.getObject("arguments");
  const auto variablesReference =
      GetUnsigned(arguments, "variablesReference", 0);
  const int64_t start = GetSigned(arguments, "start", 0);
  const int64_t count = GetSigned(arguments, "count", 0);
  bool hex = false;
  auto format = arguments->getObject("format");
  if (format)
    hex = GetBoolean(format, "hex", false);

  if (VARREF_IS_SCOPE(variablesReference)) {
    // variablesReference is one of our scopes, not an actual variable it is
    // asking for the list of args, locals or globals.
    int64_t start_idx = 0;
    int64_t num_children = 0;
    switch (variablesReference) {
    case VARREF_LOCALS:
      start_idx = start;
      num_children = g_vsc.num_locals;
      break;
    case VARREF_GLOBALS:
      start_idx = start + g_vsc.num_locals + start;
      num_children = g_vsc.num_globals;
      break;
    case VARREF_REGS:
      start_idx = start + g_vsc.num_locals + g_vsc.num_globals;
      num_children = g_vsc.num_regs;
      break;
    default:
      break;
    }
    const int64_t end_idx = start_idx + ((count == 0) ? num_children : count);
    for (auto i = start_idx; i < end_idx; ++i) {
      lldb::SBValue variable = g_vsc.variables.GetValueAtIndex(i);
      if (!variable.IsValid())
        break;
      variables.emplace_back(
          CreateVariable(variable, VARIDX_TO_VARREF(i), i, hex));
    }
  } else {
    // We are expanding a variable that has children, so we will return its
    // children.
    const int64_t var_idx = VARREF_TO_VARIDX(variablesReference);
    lldb::SBValue variable = g_vsc.variables.GetValueAtIndex(var_idx);
    if (variable.IsValid()) {
      const auto num_children = variable.GetNumChildren();
      const int64_t end_idx = start + ((count == 0) ? num_children : count);
      for (auto i = start; i < end_idx; ++i) {
        lldb::SBValue child = variable.GetChildAtIndex(i);
        if (!child.IsValid())
          break;
        if (child.MightHaveChildren()) {
          const int64_t var_idx = g_vsc.variables.GetSize();
          auto childVariablesReferences = VARIDX_TO_VARREF(var_idx);
          variables.emplace_back(
              CreateVariable(child, childVariablesReferences, var_idx, hex));
          g_vsc.variables.Append(child);
        } else {
          variables.emplace_back(CreateVariable(child, 0, INT64_MAX, hex));
        }
      }
    }
  }
  llvm::json::Object body;
  body.try_emplace("variables", std::move(variables));
  response.try_emplace("body", std::move(body));
  g_vsc.SendJSON(llvm::json::Value(std::move(response)));
}

// A request used in testing to get the details on all breakpoints that are
// currently set in the target. This helps us to test "setBreakpoints" and
// "setFunctionBreakpoints" requests to verify we have the correct set of
// breakpoints currently set in LLDB.
void request__testGetTargetBreakpoints(const llvm::json::Object &request) {
  llvm::json::Object response;
  FillResponse(request, response);
  llvm::json::Array response_breakpoints;
  for (uint32_t i = 0; g_vsc.target.GetBreakpointAtIndex(i).IsValid(); ++i) {
    auto bp = g_vsc.target.GetBreakpointAtIndex(i);
    AppendBreakpoint(bp, response_breakpoints);
  }
  llvm::json::Object body;
  body.try_emplace("breakpoints", std::move(response_breakpoints));
  response.try_emplace("body", std::move(body));
  g_vsc.SendJSON(llvm::json::Value(std::move(response)));
}

void RegisterRequestCallbacks() {
  g_vsc.RegisterRequestCallback("attach", request_attach);
  g_vsc.RegisterRequestCallback("completions", request_completions);
  g_vsc.RegisterRequestCallback("continue", request_continue);
  g_vsc.RegisterRequestCallback("configurationDone", request_configurationDone);
  g_vsc.RegisterRequestCallback("disconnect", request_disconnect);
  g_vsc.RegisterRequestCallback("evaluate", request_evaluate);
  g_vsc.RegisterRequestCallback("exceptionInfo", request_exceptionInfo);
  g_vsc.RegisterRequestCallback("initialize", request_initialize);
  g_vsc.RegisterRequestCallback("launch", request_launch);
  g_vsc.RegisterRequestCallback("next", request_next);
  g_vsc.RegisterRequestCallback("pause", request_pause);
  g_vsc.RegisterRequestCallback("scopes", request_scopes);
  g_vsc.RegisterRequestCallback("setBreakpoints", request_setBreakpoints);
  g_vsc.RegisterRequestCallback("setExceptionBreakpoints",
                                request_setExceptionBreakpoints);
  g_vsc.RegisterRequestCallback("setFunctionBreakpoints",
                                request_setFunctionBreakpoints);
  g_vsc.RegisterRequestCallback("setVariable", request_setVariable);
  g_vsc.RegisterRequestCallback("source", request_source);
  g_vsc.RegisterRequestCallback("stackTrace", request_stackTrace);
  g_vsc.RegisterRequestCallback("stepIn", request_stepIn);
  g_vsc.RegisterRequestCallback("stepOut", request_stepOut);
  g_vsc.RegisterRequestCallback("threads", request_threads);
  g_vsc.RegisterRequestCallback("variables", request_variables);
  // Custom requests
  g_vsc.RegisterRequestCallback("compileUnits", request_compileUnits);
  g_vsc.RegisterRequestCallback("modules", request_modules);
  // Testing requests
  g_vsc.RegisterRequestCallback("_testGetTargetBreakpoints",
                                request__testGetTargetBreakpoints);
}

} // anonymous namespace

static void printHelp(LLDBVSCodeOptTable &table, llvm::StringRef tool_name) {
  std::string usage_str = tool_name.str() + " options";
  table.PrintHelp(llvm::outs(), usage_str.c_str(), "LLDB VSCode", false);

  std::string examples = R"___(
EXAMPLES:
  The debug adapter can be started in two modes.

  Running lldb-vscode without any arguments will start communicating with the
  parent over stdio. Passing a port number causes lldb-vscode to start listening
  for connections on that port.

    lldb-vscode -p <port>

  Passing --wait-for-debugger will pause the process at startup and wait for a
  debugger to attach to the process.

    lldb-vscode -g
  )___";
  llvm::outs() << examples;
}

// If --launch-target is provided, this instance of lldb-vscode becomes a
// runInTerminal launcher. It will ultimately launch the program specified in
// the --launch-target argument, which is the original program the user wanted
// to debug. This is done in such a way that the actual debug adaptor can
// place breakpoints at the beginning of the program.
//
// The launcher will communicate with the debug adaptor using a fifo file in the
// directory specified in the --comm-file argument.
//
// Regarding the actual flow, this launcher will first notify the debug adaptor
// of its pid. Then, the launcher will be in a pending state waiting to be
// attached by the adaptor.
//
// Once attached and resumed, the launcher will exec and become the program
// specified by --launch-target, which is the original target the
// user wanted to run.
//
// In case of errors launching the target, a suitable error message will be
// emitted to the debug adaptor.
void LaunchRunInTerminalTarget(llvm::opt::Arg &target_arg,
                               llvm::StringRef comm_file, char *argv[]) {
#if defined(_WIN32)
  llvm::errs() << "runInTerminal is only supported on POSIX systems\n";
  exit(EXIT_FAILURE);
#else
  RunInTerminalLauncherCommChannel comm_channel(comm_file);
  if (llvm::Error err = comm_channel.NotifyPid()) {
    llvm::errs() << llvm::toString(std::move(err)) << "\n";
    exit(EXIT_FAILURE);
  }

  // We will wait to be attached with a timeout. We don't wait indefinitely
  // using a signal to prevent being paused forever.

  // This env var should be used only for tests.
  const char *timeout_env_var = getenv("LLDB_VSCODE_RIT_TIMEOUT_IN_MS");
  int timeout_in_ms =
      timeout_env_var != nullptr ? atoi(timeout_env_var) : 20000;
  if (llvm::Error err = comm_channel.WaitUntilDebugAdaptorAttaches(
          std::chrono::milliseconds(timeout_in_ms))) {
    llvm::errs() << llvm::toString(std::move(err)) << "\n";
    exit(EXIT_FAILURE);
  }

  const char *target = target_arg.getValue();
  execvp(target, argv);

  std::string error = std::strerror(errno);
  comm_channel.NotifyError(error);
  llvm::errs() << error << "\n";
  exit(EXIT_FAILURE);
#endif
}

int main(int argc, char *argv[]) {
  llvm::InitLLVM IL(argc, argv, /*InstallPipeSignalExitHandler=*/false);
  llvm::PrettyStackTraceProgram X(argc, argv);

  llvm::SmallString<256> program_path(argv[0]);
  llvm::sys::fs::make_absolute(program_path);
  g_vsc.debug_adaptor_path = program_path.str().str();

  LLDBVSCodeOptTable T;
  unsigned MAI, MAC;
  llvm::ArrayRef<const char *> ArgsArr = llvm::makeArrayRef(argv + 1, argc);
  llvm::opt::InputArgList input_args = T.ParseArgs(ArgsArr, MAI, MAC);

  if (llvm::opt::Arg *target_arg = input_args.getLastArg(OPT_launch_target)) {
    if (llvm::opt::Arg *comm_file = input_args.getLastArg(OPT_comm_file)) {
      int target_args_pos = argc;
      for (int i = 0; i < argc; i++)
        if (strcmp(argv[i], "--launch-target") == 0) {
          target_args_pos = i + 1;
          break;
        }
      LaunchRunInTerminalTarget(*target_arg, comm_file->getValue(),
                                argv + target_args_pos);
    } else {
      llvm::errs() << "\"--launch-target\" requires \"--comm-file\" to be "
                      "specified\n";
      return EXIT_FAILURE;
    }
  }

  // Initialize LLDB first before we do anything.
  lldb::SBDebugger::Initialize();

  // Terminate the debugger before the C++ destructor chain kicks in.
  auto terminate_debugger =
      llvm::make_scope_exit([] { lldb::SBDebugger::Terminate(); });

  RegisterRequestCallbacks();

  int portno = -1;

  if (input_args.hasArg(OPT_help)) {
    printHelp(T, llvm::sys::path::filename(argv[0]));
    return EXIT_SUCCESS;
  }

  if (auto *arg = input_args.getLastArg(OPT_port)) {
    auto optarg = arg->getValue();
    char *remainder;
    portno = strtol(optarg, &remainder, 0);
    if (remainder == optarg || *remainder != '\0') {
      fprintf(stderr, "'%s' is not a valid port number.\n", optarg);
      return EXIT_FAILURE;
    }
  }

#if !defined(_WIN32)
  if (input_args.hasArg(OPT_wait_for_debugger)) {
    printf("Paused waiting for debugger to attach (pid = %i)...\n", getpid());
    pause();
  }
#endif
  if (portno != -1) {
    printf("Listening on port %i...\n", portno);
    SOCKET socket_fd = AcceptConnection(portno);
    if (socket_fd >= 0) {
      g_vsc.input.descriptor = StreamDescriptor::from_socket(socket_fd, true);
      g_vsc.output.descriptor = StreamDescriptor::from_socket(socket_fd, false);
    } else {
      return EXIT_FAILURE;
    }
  } else {
    g_vsc.input.descriptor = StreamDescriptor::from_file(fileno(stdin), false);
    g_vsc.output.descriptor =
        StreamDescriptor::from_file(fileno(stdout), false);
  }
  uint32_t packet_idx = 0;
  while (!g_vsc.sent_terminated_event) {
    llvm::json::Object object;
    lldb_vscode::PacketStatus status = g_vsc.GetNextObject(object);
    if (status == lldb_vscode::PacketStatus::EndOfFile)
      break;
    if (status != lldb_vscode::PacketStatus::Success)
      return 1; // Fatal error

    if (!g_vsc.HandleObject(object))
      return 1;
    ++packet_idx;
  }

  return EXIT_SUCCESS;
}