/*
 * Xvid rate control wrapper for lavc video encoders
 *
 * Copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
 *
 * 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 "config.h"

#if HAVE_IO_H
#include <io.h>
#endif

#if HAVE_UNISTD_H
#include <unistd.h>
#endif

#include <xvid.h>

#include "libavutil/attributes.h"
#include "libavutil/file.h"

#include "avcodec.h"
#include "libxvid.h"
#include "mpegvideo.h"

av_cold int ff_xvid_rate_control_init(MpegEncContext *s)
{
    char *tmp_name;
    int fd, i;
    xvid_plg_create_t xvid_plg_create = { 0 };
    xvid_plugin_2pass2_t xvid_2pass2  = { 0 };

    fd = av_tempfile("xvidrc.", &tmp_name, 0, s->avctx);
    if (fd < 0) {
        av_log(NULL, AV_LOG_ERROR, "Can't create temporary pass2 file.\n");
        return fd;
    }

    for (i = 0; i < s->rc_context.num_entries; i++) {
        static const char frame_types[] = " ipbs";
        char tmp[256];
        RateControlEntry *rce;

        rce = &s->rc_context.entry[i];

        snprintf(tmp, sizeof(tmp), "%c %d %d %d %d %d %d\n",
                 frame_types[rce->pict_type],
                 (int) lrintf(rce->qscale / FF_QP2LAMBDA),
                 rce->i_count, s->mb_num - rce->i_count - rce->skip_count,
                 rce->skip_count,
                 (rce->i_tex_bits + rce->p_tex_bits + rce->misc_bits + 7) / 8,
                 (rce->header_bits + rce->mv_bits + 7) / 8);

        if (write(fd, tmp, strlen(tmp)) < 0) {
            int ret = AVERROR(errno);
            av_log(NULL, AV_LOG_ERROR, "Error %s writing 2pass logfile\n", av_err2str(ret));
            av_free(tmp_name);
            close(fd);
            return ret;
        }
    }

    close(fd);

    xvid_2pass2.version     = XVID_MAKE_VERSION(1, 1, 0);
    xvid_2pass2.filename    = tmp_name;
    xvid_2pass2.bitrate     = s->avctx->bit_rate;
    xvid_2pass2.vbv_size    = s->avctx->rc_buffer_size;
    xvid_2pass2.vbv_maxrate = s->avctx->rc_max_rate;
    xvid_2pass2.vbv_initial = s->avctx->rc_initial_buffer_occupancy;

    xvid_plg_create.version = XVID_MAKE_VERSION(1, 1, 0);
    xvid_plg_create.fbase   = s->avctx->time_base.den;
    xvid_plg_create.fincr   = s->avctx->time_base.num;
    xvid_plg_create.param   = &xvid_2pass2;

    if (xvid_plugin_2pass2(NULL, XVID_PLG_CREATE, &xvid_plg_create,
                           &s->rc_context.non_lavc_opaque) < 0) {
        av_log(NULL, AV_LOG_ERROR, "xvid_plugin_2pass2 failed\n");
        return -1;
    }
    return 0;
}

float ff_xvid_rate_estimate_qscale(MpegEncContext *s, int dry_run)
{
    xvid_plg_data_t xvid_plg_data = { 0 };

    xvid_plg_data.version       = XVID_MAKE_VERSION(1, 1, 0);
    xvid_plg_data.width         = s->width;
    xvid_plg_data.height        = s->height;
    xvid_plg_data.mb_width      = s->mb_width;
    xvid_plg_data.mb_height     = s->mb_height;
    xvid_plg_data.fbase         = s->avctx->time_base.den;
    xvid_plg_data.fincr         = s->avctx->time_base.num;
    xvid_plg_data.min_quant[0]  = s->avctx->qmin;
    xvid_plg_data.min_quant[1]  = s->avctx->qmin;
    xvid_plg_data.min_quant[2]  = s->avctx->qmin;   // FIXME i/b factor & offset
    xvid_plg_data.max_quant[0]  = s->avctx->qmax;
    xvid_plg_data.max_quant[1]  = s->avctx->qmax;
    xvid_plg_data.max_quant[2]  = s->avctx->qmax;   // FIXME i/b factor & offset
    xvid_plg_data.bquant_offset = 0;      //  100 * s->avctx->b_quant_offset;
    xvid_plg_data.bquant_ratio  = 100;    //      * s->avctx->b_quant_factor;

    if (!s->rc_context.dry_run_qscale) {
        if (s->picture_number) {
            xvid_plg_data.length        =
            xvid_plg_data.stats.length  = (s->frame_bits + 7) / 8;
            xvid_plg_data.frame_num     = s->rc_context.last_picture_number;
            xvid_plg_data.quant         = s->qscale;
            xvid_plg_data.type          = s->last_pict_type;
            if (xvid_plugin_2pass2(s->rc_context.non_lavc_opaque,
                                   XVID_PLG_AFTER, &xvid_plg_data, NULL)) {
                av_log(s->avctx, AV_LOG_ERROR,
                       "xvid_plugin_2pass2(handle, XVID_PLG_AFTER, ...) FAILED\n");
                return -1;
            }
        }
        s->rc_context.last_picture_number =
        xvid_plg_data.frame_num           = s->picture_number;
        xvid_plg_data.quant               = 0;
        if (xvid_plugin_2pass2(s->rc_context.non_lavc_opaque,
                               XVID_PLG_BEFORE, &xvid_plg_data, NULL)) {
            av_log(s->avctx, AV_LOG_ERROR,
                   "xvid_plugin_2pass2(handle, XVID_PLG_BEFORE, ...) FAILED\n");
            return -1;
        }
        s->rc_context.dry_run_qscale = xvid_plg_data.quant;
    }
    xvid_plg_data.quant = s->rc_context.dry_run_qscale;
    if (!dry_run)
        s->rc_context.dry_run_qscale = 0;

    // FIXME this is not exactly identical to Xvid
    if (s->pict_type == AV_PICTURE_TYPE_B)
        return xvid_plg_data.quant * FF_QP2LAMBDA * s->avctx->b_quant_factor +
            s->avctx->b_quant_offset;
    else
        return xvid_plg_data.quant * FF_QP2LAMBDA;
}

av_cold void ff_xvid_rate_control_uninit(MpegEncContext *s)
{
    xvid_plg_destroy_t xvid_plg_destroy;

    xvid_plugin_2pass2(s->rc_context.non_lavc_opaque, XVID_PLG_DESTROY,
                       &xvid_plg_destroy, NULL);
}