/**
 * Hoofbaby -- http://www.dsource.org/projects/hoofbaby
 * 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 hoofbaby.app.codec_adhoc;

import hoofbaby.util.buffer;
import tango.stdc.stdio;
import tango.stdc.stringz;
import Math = tango.math.Math;
import tango.io.device.File;
import tango.time.StopWatch;

import hoofbaby.codec.libav.avutil;
import hoofbaby.codec.libav.avcodec;
import hoofbaby.codec.libav.avformat;
import hoofbaby.codec.libav.avbuffer;

private const int STREAM_FRAME_RATE = 25;
private const double STREAM_DURATION = 5.0;
private const int STREAM_NB_FRAMES = (cast(int) (STREAM_DURATION * STREAM_FRAME_RATE));
private const int OUTBUF_SIZE = 100000;

int codec_main()
{
	StopWatch sw;
	int frameCount = 0;
	double audioCount, audioIncr, audioIncr2;
	char* voutbuf, aoutbuf;
	int res;

	AVFrame* allocFrame(int pix_fmt, int width, int height)
	{
		AVFrame* picture;
		char* buf;
		int size;

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

	void generatePicture(AVFrame* pict, int width, int height)
	{
		int x, y, i;
		i = frameCount;

		/* 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;
			}
		}
	}

	int writeVideoFrame(AVFormatContext* ctx, AVStream* stream, AVFrame* picture)
	{
		AVCodecContext* vcodec = stream.codec;
		int ret = 0;

		if(frameCount >= 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
		{
			generatePicture(picture, vcodec.width, vcodec.height);
		}

		// Encode it!
		int outSize = avcodec_encode_video(vcodec, voutbuf, OUTBUF_SIZE, picture);
		// if zero size, it means the image was buffered.. if not, write that ****!
		if(outSize > 0)
		{
			AVPacket pkt;
			av_init_packet(&pkt);

			pkt.pts = av_rescale_q(vcodec.coded_frame.pts, vcodec.time_base, stream.time_base);
			if(vcodec.coded_frame.key_frame)
				pkt.flags |= PKT_FLAG_KEY;
			pkt.stream_index = stream.index;
			pkt.data = voutbuf;
			pkt.size = outSize;

			// oh yeah!
			ret = av_write_frame(ctx, &pkt);
		}
		else
		{
			ret = 0;
		}
		
		frameCount++;
		assert(!ret, "Error writing video frame");
		return ret;
	}
	
	int writeAudioFrame(AVFormatContext* ctx, AVStream* stream, short* samples)
	{
		AVCodecContext* acodec = stream.codec;

		{
			int j, i, v;
		    short *q;

		    q = samples;
		    for(j = 0; j < acodec.frame_size; j++)
		    {
		        v = cast(int)(Math.sin(audioCount) * 10000);
		        for(i = 0; i < 2; i++) // 2 is number of channels
		            *q++ = v;
		        audioCount += audioIncr;
		        audioIncr += audioIncr2;
		    }
		}
		
		AVPacket pkt;
		av_init_packet(&pkt);
		pkt.size = avcodec_encode_audio(acodec, aoutbuf, OUTBUF_SIZE, samples);
		//pkt.pts = av_rescale_q(acodec.coded_frame.pts, acodec.time_base, acodec.time_base);
		pkt.flags |= PKT_FLAG_KEY;
		pkt.stream_index = stream.index;
		pkt.data = aoutbuf;
		
		int res = av_write_frame(ctx, &pkt) != 0;
		assert(res == 0, "Error writing audio frame");
		return res;
	}
	
	//--------------------------------------------------------------------------
	// Container format
	
	sw.start();
	
	AVOutputFormat* fmt = guess_format("asf", null, null);
	assert(fmt !is null, "Could not find format");
	
	AVFormatContext* ctx = av_alloc_format_context();
	assert(ctx !is null, "Could not allocate format context");
	scope(exit) if(ctx) av_free(ctx);
	ctx.oformat = fmt;
	//ctx.preload = cast(int) (0.5 * AV_TIME_BASE);
	ctx.max_delay = cast(int) (0.7 * AV_TIME_BASE);
	ctx.loop_output = AVFMT_NOOUTPUTLOOP;
	ctx.flags |= AVFMT_FLAG_NONBLOCK;
	
	AVFormatParameters params;
	params.prealloced_context = 1;
	params.video_codec_id = CODEC_ID_WMV2;
	params.audio_codec_id = CODEC_ID_WMAV2;
	params.width = 352;
	params.height = 288;
	params.time_base.num = 1;
	params.time_base.den = STREAM_FRAME_RATE;
	params.pix_fmt = PIX_FMT_YUV420P;
	params.channels = 2;
	params.sample_rate = 44100;
	res = av_set_parameters(ctx, null);
	assert(res >= 0, "Could not set parameters");
	
	//--------------------------------------------------------------------------
	// Video stream
	
	AVStream* vstream = av_new_stream(ctx, 0);
	assert(vstream !is null, "Could not allocate video stream");
	ctx.streams[0] = vstream;
	
	AVCodec* vcodecName = avcodec_find_encoder(CODEC_ID_WMV2);
	assert(vcodecName, "Could not find video codec");
	AVCodecContext* vcodec = vstream.codec;
	vcodec.codec_id = CODEC_ID_WMV2;
	vcodec.codec_type = CODEC_TYPE_VIDEO;
	vcodec.bit_rate = 400000;
	vcodec.width = 352;
	vcodec.height = 288;
	vcodec.gop_size = 12;
	vcodec.qmin = 3;
	vcodec.time_base.den = STREAM_FRAME_RATE;
	vcodec.time_base.num = 1;
	vcodec.pix_fmt = PIX_FMT_YUV420P;
	vcodec.flags |= CODEC_FLAG_GLOBAL_HEADER;
	res = avcodec_open(vcodec, vcodecName);
	assert(res >= 0, "Could not open video codec");
	
	//--------------------------------------------------------------------------
	// Audio stream
	
	AVStream* astream = av_new_stream(ctx, 0);
	assert(astream !is null, "Could not allocate audio stream");
	ctx.streams[1] = astream;
	
	AVCodec* acodecName = avcodec_find_encoder(CODEC_ID_WMAV2);
	assert(acodecName, "Could not find audio codec");
	AVCodecContext* acodec = astream.codec;
	acodec.codec_id = CODEC_ID_WMAV2;
	acodec.codec_type = CODEC_TYPE_AUDIO;
	acodec.bit_rate = 64000;
	acodec.sample_rate = 44100;
	acodec.channels = 2;
	acodec.flags |= CODEC_FLAG_GLOBAL_HEADER;
	audioCount = 0.0;
	audioIncr = 2 * Math.PI * 110.0 / acodec.sample_rate;
	audioIncr2 = 2 * Math.PI * 110.0 / acodec.sample_rate / acodec.sample_rate;
	res = avcodec_open(acodec, acodecName);
	assert(res >= 0, "Could not open audio codec");
	
	//--------------------------------------------------------------------------
	// Actually doing stuff
	
	// Open output file
	RingBuffer ringBuf = RingBuffer(1 << 24); // 16 MB
	scope(exit) ringBuf.free();
	ctx.pb = getBioContext(&ringBuf, 1 << 24);
	assert(ctx.pb !is null);
	assert(ctx.pb.opaque !is null);

	// Allocate a video frame and audio buffer to store stuff
	AVFrame* frame = allocFrame(PIX_FMT_YUV420P, vcodec.width, vcodec.height);
	assert(frame !is null, "Could not allocate frame");
	scope(exit) if(frame) av_free(frame);
	short* samples = cast(short*) av_malloc(acodec.frame_size * 2 * acodec.channels);
	assert(frame !is null, "Could not allocate samples");
	scope(exit) if(samples) av_free(samples);
	
	// Allocate some output buffers
	voutbuf = cast(char*) av_malloc(OUTBUF_SIZE);
	assert(voutbuf !is null, "Could not allocate video output buffer");
	scope(exit) if(voutbuf) av_free(voutbuf);
	aoutbuf = cast(char*) av_malloc(OUTBUF_SIZE);
	assert(aoutbuf !is null, "Could not allocate audio output buffer");
	scope(exit) if(aoutbuf) av_free(voutbuf);
	
	printf("Setup time %f\n", sw.stop());
	sw.start();
	
	// Write the header
	res = av_write_header(ctx);
	assert(res >= 0, "Could not write header for output file (incorrect codec paramters?)");
	
    while(true)
	{
		double audio_pts = cast(double) astream.pts.val * astream.time_base.num / astream.time_base.den;
		double video_pts = cast(double) vstream.pts.val * vstream.time_base.num / vstream.time_base.den;

		if(audio_pts >= STREAM_DURATION && video_pts >= STREAM_DURATION)
			break;

		// Write interleaved audio & video
		if(audio_pts < video_pts)
			writeAudioFrame(ctx, astream, samples);
		else
			writeVideoFrame(ctx, vstream, frame);
	}
    
	res = av_write_trailer(ctx);
	assert(res >= 0, "Could not write trailer for output file");
	
	printf("Encoding time %f\n", sw.stop());
	sw.start();
	
	scope File file = new File("biff_happy.wmv", File.WriteCreate);
	uint available = ringBuf.available;
	auto addr = ringBuf.beginRead(available);
	file.write(addr[0 .. ringBuf.available()]);
	ringBuf.endRead(available);
	file.close();
	
	printf("IO time %f\n", sw.stop());
	sw.start();
	
	return 0;
}