#include "creator.h"
#include "render.h"

static void encode(AVCodecContext *enc_ctx, AVFrame *frame, AVPacket *pkt,
                   FILE *outfile)
{
    int ret;
    /* send the frame to the encoder */
    ret = avcodec_send_frame(enc_ctx, frame);
    if (ret < 0) {
        fprintf(stderr, "error sending a frame for encoding\n");
        exit(1);
    }
    while (ret >= 0) {
        ret = avcodec_receive_packet(enc_ctx, pkt);
        if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF)
            return;
        else if (ret < 0) {
            fprintf(stderr, "error during encoding\n");
            exit(1);
        }
        printf("encoded frame %3"PRId64" (size=%5d)\n", pkt->pts, pkt->size);
        fwrite(pkt->data, 1, pkt->size, outfile);
        av_packet_unref(pkt);
    }
}
int generateVideo(filename, int length, int width, int height, int fps, int bitRate, Config *config, u32 (*sfunc) (long double, long double, u32))
{
    const char *filename;
    const AVCodec *codec;
    AVCodecContext *c= NULL;
    int i, ret, x, y;
    FILE *f;
    AVFrame *picture;
    AVPacket *pkt;
    uint8_t endcode[] = { 0, 0, 1, 0xb7 };
    if (argc <= 1) {
        fprintf(stderr, "Usage: %s <output file>\n", argv[0]);
        exit(0);
    }
    filename = argv[1];
    avcodec_register_all();
    /* find the mpeg1video encoder */
    codec = avcodec_find_encoder(AV_CODEC_ID_MPEG1VIDEO);
    if (!codec) {
        fprintf(stderr, "codec not found\n");
        exit(1);
    }
    c = avcodec_alloc_context3(codec);
    picture = av_frame_alloc();
    pkt = av_packet_alloc();
    if (!pkt)
        exit(1);

    /* put sample parameters */
    c->bit_rate = bitRate;

    /* resolution must be a multiple of two */
    if ((width*height)%2)
    	exit(1);
    c->width = width;
    c->height = height;

    /* frames per second */
    c->time_base = (AVRational){1, fps};
    c->framerate = (AVRational){fps, 1};

    /* emit one intra frame every ten frames */
    c->gop_size = 10;
    c->max_b_frames=1;
    c->pix_fmt = AV_PIX_FMT_RGBA;
    /* open it */

    if (avcodec_open2(c, codec, NULL) < 0) {
        fprintf(stderr, "could not open codec\n");
        exit(1);
    }
    f = fopen(filename, "wb");
    if (!f) {
        fprintf(stderr, "could not open %s\n", filename);
        exit(1);
    }
    picture->format = c->pix_fmt;
    picture->width  = c->width;
    picture->height = c->height;
    ret = av_frame_get_buffer(picture, 32);
    if (ret < 0) {
        fprintf(stderr, "could not alloc the frame data\n");
        exit(1);
    }


    /* encode 1 second of video */
    x_min_s = -2.0;
   	x_max_s = 1.0;
   	y_min_s= -1.0;
    y_max_s = 1.0;
    x_min = x_min_s;
    x_max = x_max_s;
    y_min = y_min_s;
    y_max = y_max_s;
    _config = config;
    _sfunc = sfunc;

    for(i=0;i<length*fps;i++) {
        fflush(stdout);
        /* make sure the frame data is writable */
        ret = av_frame_make_writable(picture);
        if (ret < 0)
            exit(1);


		s_arr = (u32 *) malloc((_config->width) * (_config->height) * sizeof(u32));
		calculate(x_min, y_min, x_max, y_max, _sfunc, s_arr);
		picture->data[0] = s_arr;

        /* prepare a dummy image */
        /* Y */
        /*for(y=0;y<c->height;y++) {
            for(x=0;x<c->width;x++) {
                picture->data[0][y * picture->linesize[0] + x] = x + y + i * 3;
            }
        }  YCbCr colorCode
        /* Cb and Cr *
        for(y=0;y<c->height/2;y++) {
            for(x=0;x<c->width/2;x++) {
                picture->data[1][y * picture->linesize[1] + x] = 128 + y + i * 2;
                picture->data[2][y * picture->linesize[2] + x] = 64 + x + i * 5;
            }
        } */
        picture->pts = i;
        /* encode the image */
        encode(c, picture, pkt, f);
    }
    /* flush the encoder */
    encode(c, NULL, pkt, f);
    /* add sequence end code to have a real MPEG file */
    fwrite(endcode, 1, sizeof(endcode), f);
    fclose(f);
    avcodec_free_context(&c);
    av_frame_free(&picture);
    av_packet_free(&pkt);
    return 0;
}