/*

 * Sun Rasterfile (.sun/.ras/im{1,8,24}/.sunras) image encoder

 * Copyright (c) 2012 Aneesh Dogra (lionaneesh) <lionaneesh@gmail.com>

 *

 * This file is part of FFmpeg.

 *

 * FFmpeg is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * FFmpeg 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

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with FFmpeg; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

 */

#include "libavutil/opt.h"

#include "avcodec.h"

#include "bytestream.h"

#include "codec_internal.h"

#include "encode.h"

#include "sunrast.h"

typedef struct SUNRASTContext {

    AVClass *class;

    PutByteContext p;

    int depth;      ///< depth of pixel

    int length;     ///< length (bytes) of image

    int type;       ///< type of file

    int maptype;    ///< type of colormap

    int maplength;  ///< length (bytes) of colormap

    int size;

} SUNRASTContext;

static void sunrast_image_write_header(AVCodecContext *avctx)

{

    SUNRASTContext *s = avctx->priv_data;

    bytestream2_put_be32u(&s->p, RAS_MAGIC);

    bytestream2_put_be32u(&s->p, avctx->width);

    bytestream2_put_be32u(&s->p, avctx->height);

    bytestream2_put_be32u(&s->p, s->depth);

    bytestream2_put_be32u(&s->p, s->length);

    bytestream2_put_be32u(&s->p, s->type);

    bytestream2_put_be32u(&s->p, s->maptype);

    bytestream2_put_be32u(&s->p, s->maplength);

}

static void sunrast_image_write_image(AVCodecContext *avctx,

                                      const uint8_t *pixels,

                                      const uint32_t *palette_data,

                                      int linesize)

{

    SUNRASTContext *s = avctx->priv_data;

    const uint8_t *ptr;

    int len, alen, x, y;

    if (s->maplength) {     // palettized

        PutByteContext pb_r, pb_g;

        int len = s->maplength / 3;

        pb_r = s->p;

        bytestream2_skip_p(&s->p, len);

        pb_g = s->p;

        bytestream2_skip_p(&s->p, len);

        for (x = 0; x < len; x++) {

            uint32_t pixel = palette_data[x];

            bytestream2_put_byteu(&pb_r, (pixel >> 16) & 0xFF);

            bytestream2_put_byteu(&pb_g, (pixel >> 8)  & 0xFF);

            bytestream2_put_byteu(&s->p,  pixel        & 0xFF);

        }

    }

    len  = (s->depth * avctx->width + 7) >> 3;

    alen = len + (len & 1);

    ptr  = pixels;

     if (s->type == RT_BYTE_ENCODED) {

        uint8_t value, value2;

        int run;

        ptr = pixels;

#define GET_VALUE y >= avctx->height ? 0 : x >= len ? ptr[len-1] : ptr[x]

        x = 0, y = 0;

        value2 = GET_VALUE;

        while (y < avctx->height) {

            run = 1;

            value = value2;

            x++;

            if (x >= alen) {

                x = 0;

                ptr += linesize, y++;

            }

            value2 = GET_VALUE;

            while (value2 == value && run < 256 && y < avctx->height) {

                x++;

                run++;

                if (x >= alen) {

                    x = 0;

                    ptr += linesize, y++;

                }

                value2 = GET_VALUE;

            }

            if (run > 2 || value == RLE_TRIGGER) {

                bytestream2_put_byteu(&s->p, RLE_TRIGGER);

                bytestream2_put_byteu(&s->p, run - 1);

                if (run > 1)

                    bytestream2_put_byteu(&s->p, value);

            } else if (run == 1) {

                bytestream2_put_byteu(&s->p, value);

            } else

                bytestream2_put_be16u(&s->p, (value << 8) | value);

        }

        // update data length for header

        s->length = bytestream2_tell_p(&s->p) - 32 - s->maplength;

    } else {

        for (y = 0; y < avctx->height; y++) {

            bytestream2_put_buffer(&s->p, ptr, len);

            if (len < alen)

                bytestream2_put_byteu(&s->p, 0);

            ptr += linesize;

        }

    }

}

static av_cold int sunrast_encode_init(AVCodecContext *avctx)

{

    SUNRASTContext *s = avctx->priv_data;

    // adjust boolean option to RT equivalent

    s->type++;

    s->maptype                    = RMT_NONE;

    s->maplength                  = 0;

    switch (avctx->pix_fmt) {

    case AV_PIX_FMT_MONOWHITE:

        s->depth = 1;

        break;

    case AV_PIX_FMT_PAL8 :

        s->maptype   = RMT_EQUAL_RGB;

        s->maplength = 3 * 256;

        /* fall-through */

    case AV_PIX_FMT_GRAY8:

        s->depth = 8;

        break;

    case AV_PIX_FMT_BGR24:

        s->depth = 24;

        break;

    default:

        return AVERROR_BUG;

    }

    s->length = avctx->height * (FFALIGN(avctx->width * s->depth, 16) >> 3);

    s->size   = 32 + s->maplength + s->length * s->type;

    return 0;

}

static int sunrast_encode_frame(AVCodecContext *avctx,  AVPacket *avpkt,

                                const AVFrame *frame, int *got_packet_ptr)

{

    SUNRASTContext *s = avctx->priv_data;

    int ret;

    if ((ret = ff_alloc_packet(avctx, avpkt, s->size)) < 0)

        return ret;

    bytestream2_init_writer(&s->p, avpkt->data, avpkt->size);

    sunrast_image_write_header(avctx);

    sunrast_image_write_image(avctx, frame->data[0],

                              (const uint32_t *)frame->data[1],

                              frame->linesize[0]);

    // update data length in header after RLE

    if (s->type == RT_BYTE_ENCODED)

        AV_WB32(&avpkt->data[16], s->length);

    *got_packet_ptr = 1;

    avpkt->size = bytestream2_tell_p(&s->p);

    return 0;

}

#define OFFSET(x) offsetof(SUNRASTContext, x)

#define VE AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_ENCODING_PARAM

static const AVOption options[] = {

    { "rle", "Use run-length compression", OFFSET(type), AV_OPT_TYPE_INT, { .i64 = 1 }, 0, 1, VE },

    { NULL },

};

static const AVClass sunrast_class = {

    .class_name = "sunrast",

    .item_name  = av_default_item_name,

    .option     = options,

    .version    = LIBAVUTIL_VERSION_INT,

};

const FFCodec ff_sunrast_encoder = {

    .p.name         = "sunrast",

    CODEC_LONG_NAME("Sun Rasterfile image"),

    .p.type         = AVMEDIA_TYPE_VIDEO,

    .p.id           = AV_CODEC_ID_SUNRAST,

    .p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE,

    .priv_data_size = sizeof(SUNRASTContext),

    .init           = sunrast_encode_init,

    FF_CODEC_ENCODE_CB(sunrast_encode_frame),

    .p.priv_class   = &sunrast_class,

    CODEC_PIXFMTS(AV_PIX_FMT_BGR24,

                  AV_PIX_FMT_PAL8,

                  AV_PIX_FMT_GRAY8,

                  AV_PIX_FMT_MONOWHITE),

};