/*

 * Copyright (c) 2011  Justin Ruggles

 *

 * 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

 */

/**

 * @file

 * ADX audio parser

 *

 * Splits packets into individual blocks.

 */

#include "parser.h"

#include "adx.h"

#include "parser_internal.h"

typedef struct ADXParseContext {

    ParseContext pc;

    int header_size;

    int block_size;

    int remaining;

} ADXParseContext;

static int adx_parse(AVCodecParserContext *s1,

                           AVCodecContext *avctx,

                           const uint8_t **poutbuf, int *poutbuf_size,

                           const uint8_t *buf, int buf_size)

{

    ADXParseContext *s = s1->priv_data;

    ParseContext *pc = &s->pc;

    int next = END_NOT_FOUND;

    int i;

    uint64_t state = pc->state64;

    if (!s->header_size) {

        for (i = 0; i < buf_size; i++) {

            state = (state << 8) | buf[i];

            /* check for fixed fields in ADX header for possible match */

            if ((state & 0xFFFF0000FFFFFF00) == 0x8000000003120400ULL) {

                int channels    = state & 0xFF;

                int header_size = ((state >> 32) & 0xFFFF) + 4;

                if (channels > 0 && header_size >= 8) {

                    s->header_size = header_size;

                    s->block_size  = BLOCK_SIZE * channels;

                    s->remaining   = i - 7 + s->header_size + s->block_size;

                    break;

                }

            }

        }

        pc->state64 = state;

    }

    if (s->header_size) {

        if (!s->remaining)

            s->remaining = s->block_size;

        if (s->remaining <= buf_size) {

            next = s->remaining;

            s->remaining = 0;

        } else

            s->remaining -= buf_size;

    } else if (avctx->ch_layout.nb_channels > 0) {

        if (!s->block_size)

            s->block_size = avctx->ch_layout.nb_channels * BLOCK_SIZE;

        if (!s->remaining)

            s->remaining = s->block_size;

        if (s->remaining <= buf_size) {

            next = s->remaining;

            s->remaining = 0;

        } else

            s->remaining -= buf_size;

    }

    if (ff_combine_frame(pc, next, &buf, &buf_size) < 0 || !buf_size) {

        *poutbuf      = NULL;

        *poutbuf_size = 0;

        return buf_size;

    }

    s1->duration = BLOCK_SAMPLES;

    *poutbuf = buf;

    *poutbuf_size = buf_size;

    return next;

}

const FFCodecParser ff_adx_parser = {

    PARSER_CODEC_LIST(AV_CODEC_ID_ADPCM_ADX),

    .priv_data_size = sizeof(ADXParseContext),

    .parse          = adx_parse,

    .close          = ff_parse_close,

};