/**
* Mime on Fire (mime) -- Simple UPnP server for XBOX360
* Copyright (C) 2009 Robert Fraser
* 
* This program is free software; you can redistribute it andor
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
* 
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
* GNU General Public License for more details.
*/
module mime.app.main;

// Imports for whole program (just link to them)
import tango.stdc.stdarg; // Must be linked in to prevent strange linker errors
debug import tango.core.stacktrace.TraceExceptions;
import NONE = mime.codec.libav.mingw;

import Math = tango.math.Math;
import tango.stdc.stdlib;
import tango.stdc.stdio;
import tango.stdc.stringz;
import tango.core.Array;

import mime.codec.libav.avutil;
import mime.codec.libav.avcodec;
import mime.codec.libav.avformat;
import mime.codec.libav.swscale;

/* 5 seconds stream duration */
const STREAM_DURATION = 5.0;
const STREAM_FRAME_RATE = 25; /* 25 images/s */
const STREAM_NB_FRAMES = (cast(int)(STREAM_DURATION * STREAM_FRAME_RATE));
const STREAM_PIX_FMT = PIX_FMT_YUV420P; /* default pix_fmt */
static int sws_flags = SWS_BICUBIC;


private bool containsString(char* haystack, char[] needle)
{
	char[] sHaystack = fromStringz(haystack);
	return sHaystack.find(needle) < sHaystack.length;
}

/**************************************************************/
/* audio output */


float t, tincr, tincr2;
short *samples;
char *audio_outbuf;
int audio_outbuf_size;
int audio_input_frame_size;

/*
 * add an audio output stream
 */
static AVStream *add_audio_stream(AVFormatContext *oc, int codec_id)
{
    AVCodecContext *c;
    AVStream *st;

    st = av_new_stream(oc, 1);
    if (!st) {
        fprintf(stderr, "Could not alloc stream\n");
        exit(1);
    }

    c = st.codec;
    c.codec_id = codec_id;
    c.codec_type = CODEC_TYPE_AUDIO;

    /* put sample parameters */
    c.bit_rate = 64000;
    c.sample_rate = 44100;
    c.channels = 2;
    return st;
}

static void open_audio(AVFormatContext *oc, AVStream *st)
{
    AVCodecContext *c;
    AVCodec *codec;

    c = st.codec;

    /* find the audio encoder */
    codec = avcodec_find_encoder(c.codec_id);
    if (!codec) {
        fprintf(stderr, "codec not found\n");
        exit(1);
    }

    /* open it */
    if (avcodec_open(c, codec) < 0) {
        fprintf(stderr, "could not open codec\n");
        exit(1);
    }

    /* init signal generator */
    t = 0;
    tincr = 2 * Math.PI * 110.0 / c.sample_rate;
    /* increment frequency by 110 Hz per second */
    tincr2 = 2 * Math.PI * 110.0 / c.sample_rate / c.sample_rate;

    audio_outbuf_size = 10000;
    audio_outbuf = cast(char*) av_malloc(audio_outbuf_size);

    /* ugly hack for PCM codecs (will be removed ASAP with new PCM
       support to compute the input frame size in samples */
    if (c.frame_size <= 1) {
        audio_input_frame_size = audio_outbuf_size / c.channels;
        switch(st.codec.codec_id) {
        case CODEC_ID_PCM_S16LE:
        case CODEC_ID_PCM_S16BE:
        case CODEC_ID_PCM_U16LE:
        case CODEC_ID_PCM_U16BE:
            audio_input_frame_size >>= 1;
            break;
        default:
            break;
        }
    } else {
        audio_input_frame_size = c.frame_size;
    }
    
    if(containsString(oc.oformat.name, "asf"))
        c.flags |= CODEC_FLAG_GLOBAL_HEADER;
    
    samples = cast(short*) av_malloc(audio_input_frame_size * 2 * c.channels);
}

/* prepare a 16 bit dummy audio frame of 'frame_size' samples and
   'nb_channels' channels */
static void get_audio_frame(short *samples, int frame_size, int nb_channels)
{
    int j, i, v;
    short *q;

    q = samples;
    for(j=0;j<frame_size;j++) {
        v = cast(int)(Math.sin(t) * 10000);
        for(i = 0; i < nb_channels; i++)
            *q++ = v;
        t += tincr;
        tincr += tincr2;
    }
}

static void write_audio_frame(AVFormatContext *oc, AVStream *st)
{
    AVCodecContext *c;
    AVPacket pkt;
    av_init_packet(&pkt);

    c = st.codec;

    get_audio_frame(samples, audio_input_frame_size, c.channels);

    pkt.size= avcodec_encode_audio(c, audio_outbuf, audio_outbuf_size, samples);

    pkt.pts= av_rescale_q(c.coded_frame.pts, c.time_base, st.time_base);
    pkt.flags |= PKT_FLAG_KEY;
    pkt.stream_index= st.index;
    pkt.data= audio_outbuf;

    /* write the compressed frame in the media file */
    if (av_write_frame(oc, &pkt) != 0) {
        fprintf(stderr, "Error while writing audio frame\n");
        exit(1);
    }
}

static void close_audio(AVFormatContext *oc, AVStream *st)
{
    avcodec_close(st.codec);

    av_free(samples);
    av_free(audio_outbuf);
}

/**************************************************************/
/* video output */

AVFrame *picture, tmp_picture;
char *video_outbuf;
int frame_count, video_outbuf_size;

/* add a video output stream */
static AVStream *add_video_stream(AVFormatContext *oc, int codec_id)
{
    AVCodecContext *c;
    AVStream *st;

    st = av_new_stream(oc, 0);
    if (!st) {
        fprintf(stderr, "Could not alloc stream\n");
        exit(1);
    }

    c = st.codec;
    c.codec_id = codec_id;
    c.codec_type = CODEC_TYPE_VIDEO;

    /* put sample parameters */
    c.bit_rate = 400000;
    /* resolution must be a multiple of two */
    c.width = 352;
    c.height = 288;
    /* time base: this is the fundamental unit of time (in seconds) in terms
       of which frame timestamps are represented. for fixed-fps content,
       timebase should be 1/framerate and timestamp increments should be
       identically 1. */
    c.time_base.den = STREAM_FRAME_RATE;
    c.time_base.num = 1;
    c.gop_size = 12; /* emit one intra frame every twelve frames at most */
    c.pix_fmt = STREAM_PIX_FMT;
    if (c.codec_id == CODEC_ID_MPEG2VIDEO) {
        /* just for testing, we also add B frames */
        c.max_b_frames = 2;
    }
    if (c.codec_id == CODEC_ID_MPEG1VIDEO){
        /* needed to avoid using macroblocks in which some coeffs overflow
           this doesnt happen with normal video, it just happens here as the
           motion of the chroma plane doesnt match the luma plane */
        c.mb_decision=2;
    }
    // some formats want stream headers to be separate
    if(containsString(oc.oformat.name, "mp4") || 
       containsString(oc.oformat.name, "mpeg4") ||
       containsString(oc.oformat.name, "asf") ||
       containsString(oc.oformat.name, "mov") || 
       containsString(oc.oformat.name, "3gp"))
        c.flags |= CODEC_FLAG_GLOBAL_HEADER;

    return st;
}

static AVFrame *alloc_picture(int pix_fmt, int width, int height)
{
    AVFrame *picture;
    char *picture_buf;
    int size;

    picture = avcodec_alloc_frame();
    if (!picture)
        return null;
    size = avpicture_get_size(pix_fmt, width, height);
    picture_buf = cast(char*) av_malloc(size);
    if (!picture_buf) {
        av_free(picture);
        return null;
    }
    avpicture_fill(cast(AVPicture *)picture, picture_buf,
                   pix_fmt, width, height);
    return picture;
}

static void open_video(AVFormatContext *oc, AVStream *st)
{
    AVCodec *codec;
    AVCodecContext *c;

    c = st.codec;

    /* find the video encoder */
    codec = avcodec_find_encoder(c.codec_id);
    if (!codec) {
        fprintf(stderr, "codec not found\n");
        exit(1);
    }

    /* open the codec */
    if (avcodec_open(c, codec) < 0) {
        fprintf(stderr, "could not open codec\n");
        exit(1);
    }

    video_outbuf = null;
    if (!(oc.oformat.flags & AVFMT_RAWPICTURE)) {
        /* allocate output buffer */
        /* XXX: API change will be done */
        /* buffers passed into lav* can be allocated any way you prefer,
           as long as they're aligned enough for the architecture, and
           they're freed appropriately (such as using av_free for buffers
           allocated with av_malloc) */
        video_outbuf_size = 200000;
        video_outbuf = cast(char*) av_malloc(video_outbuf_size);
    }

    /* allocate the encoded raw picture */
    picture = alloc_picture(c.pix_fmt, c.width, c.height);
    if (!picture) {
        fprintf(stderr, "Could not allocate picture\n");
        exit(1);
    }

    /* if the output format is not YUV420P, then a temporary YUV420P
       picture is needed too. It is then converted to the required
       output format */
    tmp_picture = null;
    if (c.pix_fmt != PIX_FMT_YUV420P) {
        tmp_picture = alloc_picture(PIX_FMT_YUV420P, c.width, c.height);
        if (!tmp_picture) {
            fprintf(stderr, "Could not allocate temporary picture\n");
            exit(1);
        }
    }
}

/* prepare a dummy image */
static void fill_yuv_image(AVFrame *pict, int frame_index, int width, int height)
{
    int x, y, i;

    i = frame_index;

    /* Y */
    for(y=0;y<height;y++) {
        for(x=0;x<width;x++) {
            pict.data[0][y * pict.linesize[0] + x] = x + y + i * 3;
        }
    }

    /* Cb and Cr */
    for(y=0;y<height/2;y++) {
        for(x=0;x<width/2;x++) {
            pict.data[1][y * pict.linesize[1] + x] = 128 + y + i * 2;
            pict.data[2][y * pict.linesize[2] + x] = 64 + x + i * 5;
        }
    }
}

static void write_video_frame(AVFormatContext *oc, AVStream *st)
{
    int out_size, ret;
    AVCodecContext *c;
    static SwsContext *img_convert_ctx;

    c = st.codec;

    if (frame_count >= STREAM_NB_FRAMES) {
        /* no more frame to compress. The codec has a latency of a few
           frames if using B frames, so we get the last frames by
           passing the same picture again */
    } else {
        if (c.pix_fmt != PIX_FMT_YUV420P) {
            /* as we only generate a YUV420P picture, we must convert it
               to the codec pixel format if needed */
            if (img_convert_ctx == null) {
                img_convert_ctx = sws_getContext(c.width, c.height,
                                                 PIX_FMT_YUV420P,
                                                 c.width, c.height,
                                                 c.pix_fmt,
                                                 sws_flags, null, null, null);
                if (img_convert_ctx == null) {
                    fprintf(stderr, "Cannot initialize the conversion context\n");
                    exit(1);
                }
            }
            fill_yuv_image(tmp_picture, frame_count, c.width, c.height);
            sws_scale(img_convert_ctx, tmp_picture.data.ptr, tmp_picture.linesize.ptr,
                      0, c.height, picture.data.ptr, picture.linesize.ptr);
        } else {
            fill_yuv_image(picture, frame_count, c.width, c.height);
        }
    }


    if (oc.oformat.flags & AVFMT_RAWPICTURE) {
        /* raw video case. The API will change slightly in the near
           futur for that */
        AVPacket pkt;
        av_init_packet(&pkt);

        pkt.flags |= PKT_FLAG_KEY;
        pkt.stream_index= st.index;
        pkt.data= cast(char *)picture;
        pkt.size= AVPicture.sizeof;

        ret = av_write_frame(oc, &pkt);
    } else {
        /* encode the image */
        out_size = avcodec_encode_video(c, video_outbuf, video_outbuf_size, picture);
        /* if zero size, it means the image was buffered */
        if (out_size > 0) {
            AVPacket pkt;
            av_init_packet(&pkt);

            pkt.pts= av_rescale_q(c.coded_frame.pts, c.time_base, st.time_base);
            if(c.coded_frame.key_frame)
                pkt.flags |= PKT_FLAG_KEY;
            pkt.stream_index= st.index;
            pkt.data= video_outbuf;
            pkt.size= out_size;

            /* write the compressed frame in the media file */
            ret = av_write_frame(oc, &pkt);
        } else {
            ret = 0;
        }
    }
    if (ret != 0) {
        fprintf(stderr, "Error while writing video frame\n");
        exit(1);
    }
    frame_count++;
}

static void close_video(AVFormatContext *oc, AVStream *st)
{
    avcodec_close(st.codec);
    av_free(picture.data[0]);
    av_free(picture);
    if (tmp_picture) {
        av_free(tmp_picture.data[0]);
        av_free(tmp_picture);
    }
    av_free(video_outbuf);
}

/**************************************************************/
/* media file output */

int main(char[][] args)
{	
    char *filename;
    AVOutputFormat *fmt;
    AVFormatContext *oc;
    AVStream *audio_st, video_st;
    double audio_pts, video_pts;
    int i;

    /* initialize libavcodec, and register all codecs and formats */
    av_register_all();
    
    version(none)
    {
    	char* codecName(int codec_id)
    	{
    		auto codec = avcodec_find_encoder(codec_id);
    		return codec ? codec.name : toStringz("NONE");
    		
    	}
    	
    	AVOutputFormat* fmt2 = first_oformat;
    	printf("format (extension, video codec, audio codec)\n");
    	while(fmt2)
    	{
    		printf("%s (.%s, %s, %s)\n", fmt2.name, fmt2.extensions, codecName(fmt2.video_codec), codecName(fmt2.audio_codec));
    		fmt2 = fmt2.next;
    	}
    }
    
    version(none)
    {
    	// List codecs
	    AVCodec* codec = av_codec_next(null); // Get first
		while(codec)
		{
			if(codec.type == CODEC_TYPE_VIDEO)
			{
				printf("%d - %s (%s)\n", codec.id, codec.name, codec.long_name);
			}
			Lnext: codec = av_codec_next(codec);
		}
    }

    filename = toStringz("biff_happy.m4v");
    
    fmt = guess_format(toStringz("m4v"), null, null);
    if (!fmt) {
        fprintf(stderr, "Could not find suitable output format\n");
        exit(1);
    }

    /* allocate the output media context */
    oc = av_alloc_format_context();
    if (!oc) {
        fprintf(stderr, "Memory error\n");
        exit(1);
    }
    oc.oformat = fmt;
    snprintf(oc.filename.ptr, oc.filename.sizeof, "%s", filename);

    /* add the audio and video streams using the default format codecs
       and initialize the codecs */
    video_st = null;
    audio_st = null;
    // WORKAREA use the right profile for mpeg4 encoding (MP4 2 Advanced Simple)
    if (fmt.video_codec != CODEC_ID_NONE) {
        video_st = add_video_stream(oc, fmt.video_codec);
    }
    // WORKAREA -- we want to be doing this with AAC - http://blogs.msdn.com/xboxteam/archive/2007/11/30/december-2007-video-playback-faq.aspx
    /* if (fmt.audio_codec != CODEC_ID_NONE) {
        audio_st = add_audio_stream(oc, fmt.audio_codec);
    } */

    /* set the output parameters (must be done even if no
       parameters). */
    if (av_set_parameters(oc, null) < 0) {
        fprintf(stderr, "Invalid output format parameters\n");
        exit(1);
    }

    dump_format(oc, 0, filename, 1);

    /* now that all the parameters are set, we can open the audio and
       video codecs and allocate the necessary encode buffers */
    if (video_st)
        open_video(oc, video_st);
    if (audio_st)
        open_audio(oc, audio_st);

    /* open the output file, if needed */
    if (!(fmt.flags & AVFMT_NOFILE)) {
        if (url_fopen(&oc.pb, filename, URL_WRONLY) < 0) {
            fprintf(stderr, "Could not open '%s'\n", filename);
            exit(1);
        }
    }

    /* write the stream header, if any */
    av_write_header(oc);

    for(;;) {
        /* compute current audio and video time */
        if (audio_st)
            audio_pts = cast(double)audio_st.pts.val * audio_st.time_base.num / audio_st.time_base.den;
        else
            audio_pts = 0.0;

        if (video_st)
            video_pts = cast(double)video_st.pts.val * video_st.time_base.num / video_st.time_base.den;
        else
            video_pts = 0.0;

        if ((!audio_st || audio_pts >= STREAM_DURATION) &&
            (!video_st || video_pts >= STREAM_DURATION))
            break;

        /* write interleaved audio and video frames */
        if (!video_st || (video_st && audio_st && audio_pts < video_pts)) {
            write_audio_frame(oc, audio_st);
        } else {
            write_video_frame(oc, video_st);
        }
    }

    /* close each codec */
    if (video_st)
        close_video(oc, video_st);
    if (audio_st)
        close_audio(oc, audio_st);

    /* write the trailer, if any */
    av_write_trailer(oc);

    /* free the streams */
    for(i = 0; i < oc.nb_streams; i++) {
        av_freep(&oc.streams[i].codec);
        av_freep(&oc.streams[i]);
    }

    if (!(fmt.flags & AVFMT_NOFILE)) {
        /* close the output file */
    }

    /* free the stream */
    av_free(oc);

    return 0;
}