// MIT License
//
// Copyright (c) 2022-2025 Advanced Micro Devices, Inc. All Rights Reserved.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.

#include "mproc.hpp"
#include "common.hpp"
#include "debug.hpp"

#include <fstream>
#include <set>
#include <sstream>
#include <string>
#include <sys/wait.h>
#include <thread>
#include <unistd.h>

namespace rocprofsys
{
namespace mproc
{
std::set<int>
get_concurrent_processes(int _ppid)
{
    std::set<int> _children = {};
    if(_ppid > 0)
    {
        auto          _inp = JOIN('/', "/proc", _ppid, "task", _ppid, "children");
        std::ifstream _ifs{ _inp };
        if(!_ifs)
        {
            ROCPROFSYS_VERBOSE_F(2, "Warning! File '%s' cannot be read\n", _inp.c_str());
            return _children;
        }

        while(_ifs)
        {
            int _v = -1;
            _ifs >> _v;
            if(!_ifs.good() || _ifs.eof()) break;
            if(_v < 0) continue;
            _children.emplace(_v);
        }
    }
    return _children;
}

int
get_process_index(int _pid, int _ppid)
{
    auto _children = get_concurrent_processes(_ppid);
    for(auto itr = _children.begin(); itr != _children.end(); ++itr)
    {
        if(*itr == _pid) return std::distance(_children.begin(), itr);
    }
    return -1;
}

int
wait_pid(pid_t _pid, int _opts)
{
    int   _status = 0;
    pid_t _pid_v  = -1;
    _opts |= WUNTRACED;
    do
    {
        if((_opts & WNOHANG) > 0)
        {
            std::this_thread::yield();
            std::this_thread::sleep_for(std::chrono::milliseconds{ 100 });
        }
        _pid_v = waitpid(_pid, &_status, _opts);
    } while(_pid_v <= 0);
    return _status;
}

int
diagnose_status(pid_t _pid, int _status, int _verbose)
{
    if(_verbose >= 3)
    {
        fflush(stderr);
        fflush(stdout);
        std::cout << std::flush;
        std::cerr << std::flush;
    }

    bool _normal_exit      = (WIFEXITED(_status) > 0);
    bool _unhandled_signal = (WIFSIGNALED(_status) > 0);
    bool _core_dump        = (WCOREDUMP(_status) > 0);
    bool _stopped          = (WIFSTOPPED(_status) > 0);
    int  _exit_status      = WEXITSTATUS(_status);
    int  _stop_signal      = (_stopped) ? WSTOPSIG(_status) : 0;
    int  _ec               = (_unhandled_signal) ? WTERMSIG(_status) : 0;

    if(_verbose >= 4)
    {
        TIMEMORY_PRINTF_INFO(
            stderr,
            "diagnosing status for process %i :: status: %i... normal exit: %s, "
            "unhandled signal: %s, core dump: %s, stopped: %s, exit status: %i, stop "
            "signal: %i, exit code: %i\n",
            _pid, _status, std::to_string(_normal_exit).c_str(),
            std::to_string(_unhandled_signal).c_str(), std::to_string(_core_dump).c_str(),
            std::to_string(_stopped).c_str(), _exit_status, _stop_signal, _ec);
    }
    else if(_verbose >= 3)
    {
        TIMEMORY_PRINTF_INFO(stderr,
                             "diagnosing status for process %i :: status: %i ...\n", _pid,
                             _status);
    }

    if(!_normal_exit)
    {
        if(_ec == 0) _ec = EXIT_FAILURE;
        if(_verbose >= 0)
        {
            TIMEMORY_PRINTF_FATAL(
                stderr, "process %i terminated abnormally. exit code: %i\n", _pid, _ec);
        }
    }

    if(_stopped)
    {
        if(_verbose >= 0)
        {
            TIMEMORY_PRINTF_FATAL(stderr,
                                  "process %i stopped with signal %i. exit code: %i\n",
                                  _pid, _stop_signal, _ec);
        }
    }

    if(_core_dump)
    {
        if(_verbose >= 0)
        {
            TIMEMORY_PRINTF_FATAL(
                stderr, "process %i terminated and produced a core dump. exit code: %i\n",
                _pid, _ec);
        }
    }

    if(_unhandled_signal)
    {
        if(_verbose >= 0)
        {
            TIMEMORY_PRINTF_FATAL(stderr,
                                  "process %i terminated because it received a signal "
                                  "(%i) that was not handled. exit code: %i\n",
                                  _pid, _ec, _ec);
        }
    }

    if(!_normal_exit && _exit_status > 0)
    {
        if(_verbose >= 0)
        {
            if(_exit_status == 127)
            {
                TIMEMORY_PRINTF_FATAL(
                    stderr, "execv in process %i failed. exit code: %i\n", _pid, _ec);
            }
            else
            {
                TIMEMORY_PRINTF_FATAL(
                    stderr,
                    "process %i terminated with a non-zero status. exit code: %i\n", _pid,
                    _ec);
            }
        }
    }

    return _ec;
}
}  // namespace mproc
}  // namespace rocprofsys