//===-- RNBContext.cpp ------------------------------------------*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
//  Created by Greg Clayton on 12/12/07.
//
//===----------------------------------------------------------------------===//

#include "RNBContext.h"

#include <sys/stat.h>
#include <sstream>

#if defined (__APPLE__)
#include <pthread.h>
#include <sched.h>
#endif

#include "RNBRemote.h"
#include "DNB.h"
#include "DNBLog.h"
#include "CFString.h"


//----------------------------------------------------------------------
// Destructor
//----------------------------------------------------------------------
RNBContext::~RNBContext()
{
    SetProcessID (INVALID_NUB_PROCESS);
}

//----------------------------------------------------------------------
// RNBContext constructor
//----------------------------------------------------------------------

const char *
RNBContext::EnvironmentAtIndex (size_t index)
{
    if (index < m_env_vec.size())
        return m_env_vec[index].c_str();
    else
        return NULL;
}


const char *
RNBContext::ArgumentAtIndex (size_t index)
{
    if (index < m_arg_vec.size())
        return m_arg_vec[index].c_str();
    else
        return NULL;
}

bool
RNBContext::SetWorkingDirectory (const char *path)
{
    struct stat working_directory_stat;
    if (::stat (path, &working_directory_stat) != 0)
    {
        m_working_directory.clear();
        return false;
    }
    m_working_directory.assign(path);
    return true;
}


void
RNBContext::SetProcessID (nub_process_t pid)
{
    // Delete and events we created
    if (m_pid != INVALID_NUB_PROCESS)
    {
        StopProcessStatusThread ();
        // Unregister this context as a client of the process's events.
    }
    // Assign our new process ID
    m_pid = pid;

    if (pid != INVALID_NUB_PROCESS)
    {
        StartProcessStatusThread ();
    }
}

void
RNBContext::StartProcessStatusThread()
{
    DNBLogThreadedIf(LOG_RNB_PROC, "RNBContext::%s called", __FUNCTION__);
    if ((m_events.GetEventBits() & event_proc_thread_running) == 0)
    {
        int err = ::pthread_create (&m_pid_pthread, NULL, ThreadFunctionProcessStatus, this);
        if (err == 0)
        {
            // Our thread was successfully kicked off, wait for it to
            // set the started event so we can safely continue
            m_events.WaitForSetEvents (event_proc_thread_running);
            DNBLogThreadedIf(LOG_RNB_PROC, "RNBContext::%s thread got started!", __FUNCTION__);
        }
        else
        {
            DNBLogThreadedIf(LOG_RNB_PROC, "RNBContext::%s thread failed to start: err = %i", __FUNCTION__, err);
            m_events.ResetEvents (event_proc_thread_running);
            m_events.SetEvents (event_proc_thread_exiting);
        }
    }
}

void
RNBContext::StopProcessStatusThread()
{
    DNBLogThreadedIf(LOG_RNB_PROC, "RNBContext::%s called", __FUNCTION__);
    if ((m_events.GetEventBits() & event_proc_thread_running) == event_proc_thread_running)
    {
        struct timespec timeout_abstime;
        DNBTimer::OffsetTimeOfDay(&timeout_abstime, 2, 0);
        // Wait for 2 seconds for the rx thread to exit
        if (m_events.WaitForSetEvents(RNBContext::event_proc_thread_exiting, &timeout_abstime) == RNBContext::event_proc_thread_exiting)
        {
            DNBLogThreadedIf(LOG_RNB_PROC, "RNBContext::%s thread stopped as requeseted", __FUNCTION__);
        }
        else
        {
            DNBLogThreadedIf(LOG_RNB_PROC, "RNBContext::%s thread did not stop in 2 seconds...", __FUNCTION__);
            // Kill the RX thread???
        }
    }
}

//----------------------------------------------------------------------
// This thread's sole purpose is to watch for any status changes in the
// child process.
//----------------------------------------------------------------------
void*
RNBContext::ThreadFunctionProcessStatus(void *arg)
{
    RNBRemoteSP remoteSP(g_remoteSP);
    RNBRemote* remote = remoteSP.get();
    if (remote == NULL)
        return NULL;
    RNBContext& ctx = remote->Context();

    nub_process_t pid = ctx.ProcessID();
    DNBLogThreadedIf(LOG_RNB_PROC, "RNBContext::%s (arg=%p, pid=%4.4x): thread starting...", __FUNCTION__, arg, pid);
    ctx.Events().SetEvents (RNBContext::event_proc_thread_running);

#if defined (__APPLE__)
    pthread_setname_np ("child process status watcher thread");
#if defined (__arm__) || defined (__arm64__) || defined (__aarch64__)
    struct sched_param thread_param;
    int thread_sched_policy;
    if (pthread_getschedparam(pthread_self(), &thread_sched_policy, &thread_param) == 0) 
    {
        thread_param.sched_priority = 47;
        pthread_setschedparam(pthread_self(), thread_sched_policy, &thread_param);
    }
#endif
#endif

    bool done = false;
    while (!done)
    {
        DNBLogThreadedIf(LOG_RNB_PROC, "RNBContext::%s calling DNBProcessWaitForEvent(pid, eEventProcessRunningStateChanged | eEventProcessStoppedStateChanged | eEventStdioAvailable | eEventProfileDataAvailable, true)...", __FUNCTION__);
        nub_event_t pid_status_event = DNBProcessWaitForEvents (pid, eEventProcessRunningStateChanged | eEventProcessStoppedStateChanged | eEventStdioAvailable | eEventProfileDataAvailable, true, NULL);
        DNBLogThreadedIf(LOG_RNB_PROC, "RNBContext::%s calling DNBProcessWaitForEvent(pid, eEventProcessRunningStateChanged | eEventProcessStoppedStateChanged | eEventStdioAvailable | eEventProfileDataAvailable, true) => 0x%8.8x", __FUNCTION__, pid_status_event);

        if (pid_status_event == 0)
        {
            DNBLogThreadedIf(LOG_RNB_PROC, "RNBContext::%s (pid=%4.4x) got ZERO back from DNBProcessWaitForEvent....", __FUNCTION__, pid);
        //    done = true;
        }
        else
        {
            if (pid_status_event & eEventStdioAvailable)
            {
                DNBLogThreadedIf(LOG_RNB_PROC, "RNBContext::%s (pid=%4.4x) got stdio available event....", __FUNCTION__, pid);
                ctx.Events().SetEvents (RNBContext::event_proc_stdio_available);
                // Wait for the main thread to consume this notification if it requested we wait for it
                ctx.Events().WaitForResetAck(RNBContext::event_proc_stdio_available);
            }

            if (pid_status_event & eEventProfileDataAvailable)
            {
                DNBLogThreadedIf(LOG_RNB_PROC, "RNBContext::%s (pid=%4.4x) got profile data event....", __FUNCTION__, pid);
                ctx.Events().SetEvents (RNBContext::event_proc_profile_data);
                // Wait for the main thread to consume this notification if it requested we wait for it
                ctx.Events().WaitForResetAck(RNBContext::event_proc_profile_data);
            }

            if (pid_status_event & (eEventProcessRunningStateChanged | eEventProcessStoppedStateChanged))
            {
                nub_state_t pid_state = DNBProcessGetState(pid);
                DNBLogThreadedIf(LOG_RNB_PROC, "RNBContext::%s (pid=%4.4x) got process state change: %s", __FUNCTION__, pid, DNBStateAsString(pid_state));

                // Let the main thread know there is a process state change to see
                ctx.Events().SetEvents (RNBContext::event_proc_state_changed);
                // Wait for the main thread to consume this notification if it requested we wait for it
                ctx.Events().WaitForResetAck(RNBContext::event_proc_state_changed);

                switch (pid_state)
                {
                case eStateStopped:
                    break;

                case eStateInvalid:
                case eStateExited:
                case eStateDetached:
                    done = true;
                    break;
                default:
                    break;
                }
            }

            // Reset any events that we consumed.
            DNBProcessResetEvents(pid, pid_status_event);

        }
    }
    DNBLogThreadedIf(LOG_RNB_PROC, "RNBContext::%s (arg=%p, pid=%4.4x): thread exiting...", __FUNCTION__, arg, pid);
    ctx.Events().ResetEvents(event_proc_thread_running);
    ctx.Events().SetEvents(event_proc_thread_exiting);
    return NULL;
}


const char*
RNBContext::EventsAsString (nub_event_t events, std::string& s)
{
    s.clear();
    if (events & event_proc_state_changed)
        s += "proc_state_changed ";
    if (events & event_proc_thread_running)
        s += "proc_thread_running ";
    if (events & event_proc_thread_exiting)
        s += "proc_thread_exiting ";
    if (events & event_proc_stdio_available)
        s += "proc_stdio_available ";
    if (events & event_proc_profile_data)
        s += "proc_profile_data ";
    if (events & event_read_packet_available)
        s += "read_packet_available ";
    if (events & event_read_thread_running)
        s += "read_thread_running ";
    if (events & event_read_thread_running)
        s += "read_thread_running ";
    return s.c_str();
}

const char *
RNBContext::LaunchStatusAsString (std::string& s)
{
    s.clear();

    const char *err_str = m_launch_status.AsString();
    if (err_str)
        s = err_str;
    else
    {
        char error_num_str[64];
        snprintf(error_num_str, sizeof(error_num_str), "%u", m_launch_status.Error());
        s = error_num_str;
    }
    return s.c_str();
}

bool
RNBContext::ProcessStateRunning() const
{
    nub_state_t pid_state = DNBProcessGetState(m_pid);
    return pid_state == eStateRunning || pid_state == eStateStepping;
}