#include "ffmpeg.h"

FFMPEG* ffmpegStart(const char* filename, int width, int height, int fps)
{
    int pipefd[2];

    if (pipe(pipefd) < 0)
    {
        TraceLog(LOG_ERROR, "FFMPEG: Could not create a pipe: %s", strerror(errno));
        return NULL;
    }

    pid_t child = fork();
    
    if (child < 0)
    {
        TraceLog(LOG_ERROR, "FFMPEG: could not fork a child: %s", strerror(errno));
        return NULL;
    }

    if (child == 0)
    {
        if (dup2(pipefd[READ_END], STDIN_FILENO) < 0)
        {
            TraceLog(LOG_ERROR, "FFMPEG CHILD: could not reopen read end of pipe as stdin: %s", strerror(errno));
            exit(1);
        }
        
        close(pipefd[WRITE_END]);

        char resolution[64];
        snprintf(resolution, sizeof(resolution), "%zux%zu", (size_t)width, (size_t)height);
        char framerate[64];
        snprintf(framerate, sizeof(framerate), "%zu", (size_t)fps);

        int ret = execlp("ffmpeg",
            "ffmpeg",
            "-loglevel", "verbose",
            "-y",

            "-f", "rawvideo",
            "-pix_fmt", "rgba",
            "-s", resolution,
            "-r", framerate,
            "-i", "-",
            "-c:v", "libx264",
            "-vb", "2500k",
            "-c:a", "aac",
            "-ab", "200k",
            "-pix_fmt", "yuv420p",
            filename,
            NULL
        );
        
        if (ret < 0)
        {
            TraceLog(LOG_ERROR, "FFMPEG CHILD: could not run ffmpeg as a child process: %s", strerror(errno));
            exit(1);
        }
        
        assert(0 && "unreachable");
        exit(1);
    }

    if (close(pipefd[READ_END]) < 0)
    {
        TraceLog(LOG_WARNING, "FFMPEG: could not close read end of the pipe on the parent's end: %s", strerror(errno));
    }

    FFMPEG *ffmpeg = malloc(sizeof(FFMPEG));
    assert(ffmpeg != NULL && "Buy MORE RAM lol!!");
    ffmpeg->pid = child;
    ffmpeg->pipe = pipefd[WRITE_END];
    return ffmpeg;
}

int ffmpegSendFrame(FFMPEG* ffmpeg, void* data, int widtth, int height)
{
    return 0;
}

int ffmpegEnd(FFMPEG* ffmpeg)
{
    return 0;
}