/*
 * RockChip MPP Video Decoder
 * Copyright (c) 2017 Lionel CHAZALLON
 *
 * 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 <drm_fourcc.h>
#include <pthread.h>
#include <rockchip/mpp_buffer.h>
#include <rockchip/rk_mpi.h>
#include <time.h>
#include <unistd.h>

#include "avcodec.h"
#include "codec_internal.h"
#include "decode.h"
#include "decode_bsf.h"
#include "hwconfig.h"
#include "libavutil/refstruct.h"
#include "libavutil/buffer.h"
#include "libavutil/common.h"
#include "libavutil/frame.h"
#include "libavutil/hwcontext.h"
#include "libavutil/hwcontext_drm.h"
#include "libavutil/imgutils.h"
#include "libavutil/log.h"
#include "libavutil/mem.h"

#define RECEIVE_FRAME_TIMEOUT   100
#define FRAMEGROUP_MAX_FRAMES   16
#define INPUT_MAX_PACKETS       4

typedef struct {
    MppCtx ctx;
    MppApi *mpi;
    MppBufferGroup frame_group;

    char first_packet;
    char eos_reached;

    AVBufferRef *frames_ref;
    AVBufferRef *device_ref;
} RKMPPDecoder;

typedef struct {
    AVClass *av_class;
    RKMPPDecoder *decoder;           ///< RefStruct reference
} RKMPPDecodeContext;

typedef struct {
    MppFrame frame;
    const RKMPPDecoder *decoder_ref; ///< RefStruct reference
} RKMPPFrameContext;

static MppCodingType rkmpp_get_codingtype(AVCodecContext *avctx)
{
    switch (avctx->codec_id) {
    case AV_CODEC_ID_H264:          return MPP_VIDEO_CodingAVC;
    case AV_CODEC_ID_HEVC:          return MPP_VIDEO_CodingHEVC;
    case AV_CODEC_ID_VP8:           return MPP_VIDEO_CodingVP8;
    case AV_CODEC_ID_VP9:           return MPP_VIDEO_CodingVP9;
    default:                        return MPP_VIDEO_CodingUnused;
    }
}

static uint32_t rkmpp_get_frameformat(MppFrameFormat mppformat)
{
    switch (mppformat) {
    case MPP_FMT_YUV420SP:          return DRM_FORMAT_NV12;
#ifdef DRM_FORMAT_NV12_10
    case MPP_FMT_YUV420SP_10BIT:    return DRM_FORMAT_NV12_10;
#endif
    default:                        return 0;
    }
}

static int rkmpp_write_data(AVCodecContext *avctx, uint8_t *buffer, int size, int64_t pts)
{
    RKMPPDecodeContext *rk_context = avctx->priv_data;
    RKMPPDecoder *decoder = rk_context->decoder;
    int ret;
    MppPacket packet;

    // create the MPP packet
    ret = mpp_packet_init(&packet, buffer, size);
    if (ret != MPP_OK) {
        av_log(avctx, AV_LOG_ERROR, "Failed to init MPP packet (code = %d)\n", ret);
        return AVERROR_UNKNOWN;
    }

    mpp_packet_set_pts(packet, pts);

    if (!buffer)
        mpp_packet_set_eos(packet);

    ret = decoder->mpi->decode_put_packet(decoder->ctx, packet);
    if (ret != MPP_OK) {
        if (ret == MPP_ERR_BUFFER_FULL) {
            av_log(avctx, AV_LOG_DEBUG, "Buffer full writing %d bytes to decoder\n", size);
            ret = AVERROR(EAGAIN);
        } else
            ret = AVERROR_UNKNOWN;
    }
    else
        av_log(avctx, AV_LOG_DEBUG, "Wrote %d bytes to decoder\n", size);

    mpp_packet_deinit(&packet);

    return ret;
}

static av_cold int rkmpp_close_decoder(AVCodecContext *avctx)
{
    RKMPPDecodeContext *rk_context = avctx->priv_data;
    av_refstruct_unref(&rk_context->decoder);
    return 0;
}

static void rkmpp_release_decoder(AVRefStructOpaque unused, void *obj)
{
    RKMPPDecoder *decoder = obj;

    if (decoder->mpi) {
        decoder->mpi->reset(decoder->ctx);
        mpp_destroy(decoder->ctx);
        decoder->ctx = NULL;
    }

    if (decoder->frame_group) {
        mpp_buffer_group_put(decoder->frame_group);
        decoder->frame_group = NULL;
    }

    av_buffer_unref(&decoder->frames_ref);
    av_buffer_unref(&decoder->device_ref);
}

static av_cold int rkmpp_init_decoder(AVCodecContext *avctx)
{
    RKMPPDecodeContext *rk_context = avctx->priv_data;
    RKMPPDecoder *decoder = NULL;
    MppCodingType codectype = MPP_VIDEO_CodingUnused;
    int ret;
    RK_S64 paramS64;
    RK_S32 paramS32;

    avctx->pix_fmt = AV_PIX_FMT_DRM_PRIME;

    // create a decoder and a ref to it
    decoder = av_refstruct_alloc_ext(sizeof(*decoder), 0,
                                     NULL, rkmpp_release_decoder);
    if (!decoder) {
        ret = AVERROR(ENOMEM);
        goto fail;
    }
    rk_context->decoder = decoder;

    av_log(avctx, AV_LOG_DEBUG, "Initializing RKMPP decoder.\n");

    codectype = rkmpp_get_codingtype(avctx);
    if (codectype == MPP_VIDEO_CodingUnused) {
        av_log(avctx, AV_LOG_ERROR, "Unknown codec type (%d).\n", avctx->codec_id);
        ret = AVERROR_UNKNOWN;
        goto fail;
    }

    ret = mpp_check_support_format(MPP_CTX_DEC, codectype);
    if (ret != MPP_OK) {
        av_log(avctx, AV_LOG_ERROR, "Codec type (%d) unsupported by MPP\n", avctx->codec_id);
        ret = AVERROR_UNKNOWN;
        goto fail;
    }

    // Create the MPP context
    ret = mpp_create(&decoder->ctx, &decoder->mpi);
    if (ret != MPP_OK) {
        av_log(avctx, AV_LOG_ERROR, "Failed to create MPP context (code = %d).\n", ret);
        ret = AVERROR_UNKNOWN;
        goto fail;
    }

    // initialize mpp
    ret = mpp_init(decoder->ctx, MPP_CTX_DEC, codectype);
    if (ret != MPP_OK) {
        av_log(avctx, AV_LOG_ERROR, "Failed to initialize MPP context (code = %d).\n", ret);
        ret = AVERROR_UNKNOWN;
        goto fail;
    }

    // make decode calls blocking with a timeout
    paramS32 = MPP_POLL_BLOCK;
    ret = decoder->mpi->control(decoder->ctx, MPP_SET_OUTPUT_BLOCK, &paramS32);
    if (ret != MPP_OK) {
        av_log(avctx, AV_LOG_ERROR, "Failed to set blocking mode on MPI (code = %d).\n", ret);
        ret = AVERROR_UNKNOWN;
        goto fail;
    }

    paramS64 = RECEIVE_FRAME_TIMEOUT;
    ret = decoder->mpi->control(decoder->ctx, MPP_SET_OUTPUT_BLOCK_TIMEOUT, &paramS64);
    if (ret != MPP_OK) {
        av_log(avctx, AV_LOG_ERROR, "Failed to set block timeout on MPI (code = %d).\n", ret);
        ret = AVERROR_UNKNOWN;
        goto fail;
    }

    ret = mpp_buffer_group_get_internal(&decoder->frame_group, MPP_BUFFER_TYPE_ION);
    if (ret) {
       av_log(avctx, AV_LOG_ERROR, "Failed to retrieve buffer group (code = %d)\n", ret);
       ret = AVERROR_UNKNOWN;
       goto fail;
    }

    ret = decoder->mpi->control(decoder->ctx, MPP_DEC_SET_EXT_BUF_GROUP, decoder->frame_group);
    if (ret) {
        av_log(avctx, AV_LOG_ERROR, "Failed to assign buffer group (code = %d)\n", ret);
        ret = AVERROR_UNKNOWN;
        goto fail;
    }

    ret = mpp_buffer_group_limit_config(decoder->frame_group, 0, FRAMEGROUP_MAX_FRAMES);
    if (ret) {
        av_log(avctx, AV_LOG_ERROR, "Failed to set buffer group limit (code = %d)\n", ret);
        ret = AVERROR_UNKNOWN;
        goto fail;
    }

    decoder->first_packet = 1;

    av_log(avctx, AV_LOG_DEBUG, "RKMPP decoder initialized successfully.\n");

    decoder->device_ref = av_hwdevice_ctx_alloc(AV_HWDEVICE_TYPE_DRM);
    if (!decoder->device_ref) {
        ret = AVERROR(ENOMEM);
        goto fail;
    }
    ret = av_hwdevice_ctx_init(decoder->device_ref);
    if (ret < 0)
        goto fail;

    return 0;

fail:
    av_log(avctx, AV_LOG_ERROR, "Failed to initialize RKMPP decoder.\n");
    return ret;
}

static int rkmpp_send_packet(AVCodecContext *avctx, const AVPacket *avpkt)
{
    RKMPPDecodeContext *rk_context = avctx->priv_data;
    RKMPPDecoder *decoder = rk_context->decoder;
    int ret;

    // handle EOF
    if (!avpkt->size) {
        av_log(avctx, AV_LOG_DEBUG, "End of stream.\n");
        decoder->eos_reached = 1;
        ret = rkmpp_write_data(avctx, NULL, 0, 0);
        if (ret)
            av_log(avctx, AV_LOG_ERROR, "Failed to send EOS to decoder (code = %d)\n", ret);
        return ret;
    }

    // on first packet, send extradata
    if (decoder->first_packet) {
        if (avctx->extradata_size) {
            const uint8_t *extradata;
            int extradata_size;
            ff_decode_get_extradata(avctx, &extradata, &extradata_size);
            ret = rkmpp_write_data(avctx, (uint8_t*)extradata, extradata_size,
                                   avpkt->pts);
            if (ret) {
                av_log(avctx, AV_LOG_ERROR, "Failed to write extradata to decoder (code = %d)\n", ret);
                return ret;
            }
        }
        decoder->first_packet = 0;
    }

    // now send packet
    ret = rkmpp_write_data(avctx, avpkt->data, avpkt->size, avpkt->pts);
    if (ret && ret!=AVERROR(EAGAIN))
        av_log(avctx, AV_LOG_ERROR, "Failed to write data to decoder (code = %d)\n", ret);

    return ret;
}

static void rkmpp_release_frame(void *opaque, uint8_t *data)
{
    AVDRMFrameDescriptor *desc = (AVDRMFrameDescriptor *)data;
    RKMPPFrameContext *framecontext = opaque;

    mpp_frame_deinit(&framecontext->frame);
    av_refstruct_unref(&framecontext->decoder_ref);

    av_free(desc);
}

static int rkmpp_retrieve_frame(AVCodecContext *avctx, AVFrame *frame)
{
    RKMPPDecodeContext *rk_context = avctx->priv_data;
    RKMPPDecoder *decoder = rk_context->decoder;
    int ret;
    MppFrame mppframe = NULL;
    MppBuffer buffer = NULL;
    AVDRMLayerDescriptor *layer = NULL;
    int mode;
    MppFrameFormat mppformat;
    uint32_t drmformat;

    ret = decoder->mpi->decode_get_frame(decoder->ctx, &mppframe);
    if (ret != MPP_OK && ret != MPP_ERR_TIMEOUT) {
        av_log(avctx, AV_LOG_ERROR, "Failed to get a frame from MPP (code = %d)\n", ret);
        goto fail;
    }

    if (mppframe) {
        // Check whether we have a special frame or not
        if (mpp_frame_get_info_change(mppframe)) {
            AVHWFramesContext *hwframes;

            av_log(avctx, AV_LOG_INFO, "Decoder noticed an info change (%dx%d), format=%d\n",
                                        (int)mpp_frame_get_width(mppframe), (int)mpp_frame_get_height(mppframe),
                                        (int)mpp_frame_get_fmt(mppframe));

            avctx->width = mpp_frame_get_width(mppframe);
            avctx->height = mpp_frame_get_height(mppframe);

            decoder->mpi->control(decoder->ctx, MPP_DEC_SET_INFO_CHANGE_READY, NULL);

            av_buffer_unref(&decoder->frames_ref);

            decoder->frames_ref = av_hwframe_ctx_alloc(decoder->device_ref);
            if (!decoder->frames_ref) {
                ret = AVERROR(ENOMEM);
                goto fail;
            }

            mppformat = mpp_frame_get_fmt(mppframe);
            drmformat = rkmpp_get_frameformat(mppformat);

            hwframes = (AVHWFramesContext*)decoder->frames_ref->data;
            hwframes->format    = AV_PIX_FMT_DRM_PRIME;
            hwframes->sw_format = drmformat == DRM_FORMAT_NV12 ? AV_PIX_FMT_NV12 : AV_PIX_FMT_NONE;
            hwframes->width     = avctx->width;
            hwframes->height    = avctx->height;
            ret = av_hwframe_ctx_init(decoder->frames_ref);
            if (ret < 0)
                goto fail;

            // here decoder is fully initialized, we need to feed it again with data
            ret = AVERROR(EAGAIN);
            goto fail;
        } else if (mpp_frame_get_eos(mppframe)) {
            av_log(avctx, AV_LOG_DEBUG, "Received a EOS frame.\n");
            decoder->eos_reached = 1;
            ret = AVERROR_EOF;
            goto fail;
        } else if (mpp_frame_get_discard(mppframe)) {
            av_log(avctx, AV_LOG_DEBUG, "Received a discard frame.\n");
            ret = AVERROR(EAGAIN);
            goto fail;
        } else if (mpp_frame_get_errinfo(mppframe)) {
            av_log(avctx, AV_LOG_ERROR, "Received a errinfo frame.\n");
            ret = AVERROR_UNKNOWN;
            goto fail;
        }

        // here we should have a valid frame
        av_log(avctx, AV_LOG_DEBUG, "Received a frame.\n");

        // setup general frame fields
        frame->format           = AV_PIX_FMT_DRM_PRIME;
        frame->width            = mpp_frame_get_width(mppframe);
        frame->height           = mpp_frame_get_height(mppframe);
        frame->pts              = mpp_frame_get_pts(mppframe);
        frame->color_range      = mpp_frame_get_color_range(mppframe);
        frame->color_primaries  = mpp_frame_get_color_primaries(mppframe);
        frame->color_trc        = mpp_frame_get_color_trc(mppframe);
        frame->colorspace       = mpp_frame_get_colorspace(mppframe);

        mode = mpp_frame_get_mode(mppframe);
        if ((mode & MPP_FRAME_FLAG_FIELD_ORDER_MASK) == MPP_FRAME_FLAG_DEINTERLACED)
            frame->flags |= AV_FRAME_FLAG_INTERLACED;
        if ((mode & MPP_FRAME_FLAG_FIELD_ORDER_MASK) == MPP_FRAME_FLAG_TOP_FIRST)
            frame->flags |= AV_FRAME_FLAG_TOP_FIELD_FIRST;

        mppformat = mpp_frame_get_fmt(mppframe);
        drmformat = rkmpp_get_frameformat(mppformat);

        // now setup the frame buffer info
        buffer = mpp_frame_get_buffer(mppframe);
        if (buffer) {
            RKMPPFrameContext *framecontext;
            AVDRMFrameDescriptor *desc;
            // We allocate the descriptor in buf[0] jointly with a structure
            // that will allow to hold additional information
            // for properly releasing MPP frames and decoder.
            struct {
                AVDRMFrameDescriptor desc;
                RKMPPFrameContext framecontext;
            } *combined_desc = av_mallocz(sizeof(*combined_desc));
            if (!combined_desc) {
                ret = AVERROR(ENOMEM);
                goto fail;
            }
            desc         = &combined_desc->desc;
            framecontext = &combined_desc->framecontext;

            desc->nb_objects = 1;
            desc->objects[0].fd = mpp_buffer_get_fd(buffer);
            desc->objects[0].size = mpp_buffer_get_size(buffer);

            desc->nb_layers = 1;
            layer = &desc->layers[0];
            layer->format = drmformat;
            layer->nb_planes = 2;

            layer->planes[0].object_index = 0;
            layer->planes[0].offset = 0;
            layer->planes[0].pitch = mpp_frame_get_hor_stride(mppframe);

            layer->planes[1].object_index = 0;
            layer->planes[1].offset = layer->planes[0].pitch * mpp_frame_get_ver_stride(mppframe);
            layer->planes[1].pitch = layer->planes[0].pitch;

            // MPP decoder needs to be closed only when all frames have been released.
            framecontext->frame = mppframe;

            frame->data[0]  = (uint8_t *)desc;
            frame->buf[0]   = av_buffer_create((uint8_t *)desc, sizeof(*desc), rkmpp_release_frame,
                                               framecontext, AV_BUFFER_FLAG_READONLY);

            if (!frame->buf[0]) {
                av_free(combined_desc);
                ret = AVERROR(ENOMEM);
                goto fail;
            }
            framecontext->decoder_ref = av_refstruct_ref(rk_context->decoder);

            frame->hw_frames_ctx = av_buffer_ref(decoder->frames_ref);
            if (!frame->hw_frames_ctx) {
                av_frame_unref(frame);
                return AVERROR(ENOMEM);
            }

            return 0;
        } else {
            av_log(avctx, AV_LOG_ERROR, "Failed to retrieve the frame buffer, frame is dropped (code = %d)\n", ret);
            mpp_frame_deinit(&mppframe);
        }
    } else if (decoder->eos_reached) {
        return AVERROR_EOF;
    } else if (ret == MPP_ERR_TIMEOUT) {
        av_log(avctx, AV_LOG_DEBUG, "Timeout when trying to get a frame from MPP\n");
    }

    return AVERROR(EAGAIN);

fail:
    if (mppframe)
        mpp_frame_deinit(&mppframe);

    return ret;
}

static int rkmpp_receive_frame(AVCodecContext *avctx, AVFrame *frame)
{
    RKMPPDecodeContext *rk_context = avctx->priv_data;
    RKMPPDecoder *decoder = rk_context->decoder;
    int ret = MPP_NOK;
    RK_S32 usedslots, freeslots;

    if (!decoder->eos_reached) {
        // we get the available slots in decoder
        ret = decoder->mpi->control(decoder->ctx, MPP_DEC_GET_STREAM_COUNT, &usedslots);
        if (ret != MPP_OK) {
            av_log(avctx, AV_LOG_ERROR, "Failed to get decoder used slots (code = %d).\n", ret);
            return ret;
        }

        freeslots = INPUT_MAX_PACKETS - usedslots;
        if (freeslots > 0) {
            AVPacket *const pkt = avctx->internal->in_pkt;

            if (!pkt->size) {
                ret = ff_decode_get_packet(avctx, pkt);
                if (ret < 0 && ret != AVERROR_EOF) {
                    return ret;
                }
            }

            ret = rkmpp_send_packet(avctx, pkt);
            if (ret < 0 && ret != AVERROR(EAGAIN)) {
                av_packet_unref(pkt);
                av_log(avctx, AV_LOG_ERROR, "Failed to send packet to decoder (code = %d)\n", ret);
                return ret;
            } else if (ret == AVERROR(EAGAIN)) {
                // Input queue is full, don't queue more packet.
                freeslots = 0;
            } else {
                av_packet_unref(pkt);
            }
        }

        // make sure we keep decoder full
        if (freeslots > 1 && !decoder->eos_reached)
            return AVERROR(EAGAIN);
    }

    do {
        ret = rkmpp_retrieve_frame(avctx, frame);
    } while (decoder->eos_reached && ret == AVERROR(EAGAIN));

    return ret;
}

static av_cold void rkmpp_flush(AVCodecContext *avctx)
{
    RKMPPDecodeContext *rk_context = avctx->priv_data;
    RKMPPDecoder *decoder = rk_context->decoder;
    int ret = MPP_NOK;

    av_log(avctx, AV_LOG_DEBUG, "Flush.\n");

    ret = decoder->mpi->reset(decoder->ctx);
    if (ret == MPP_OK) {
        decoder->first_packet = 1;
    } else
        av_log(avctx, AV_LOG_ERROR, "Failed to reset MPI (code = %d)\n", ret);
}

static const AVCodecHWConfigInternal *const rkmpp_hw_configs[] = {
    HW_CONFIG_INTERNAL(DRM_PRIME),
    NULL
};

#define RKMPP_DEC_CLASS(NAME) \
    static const AVClass rkmpp_##NAME##_dec_class = { \
        .class_name = "rkmpp_" #NAME "_dec", \
        .version    = LIBAVUTIL_VERSION_INT, \
    };

#define RKMPP_DEC(NAME, ID, BSFS) \
    RKMPP_DEC_CLASS(NAME) \
    const FFCodec ff_##NAME##_rkmpp_decoder = { \
        .p.name         = #NAME "_rkmpp", \
        CODEC_LONG_NAME(#NAME " (rkmpp)"), \
        .p.type         = AVMEDIA_TYPE_VIDEO, \
        .p.id           = ID, \
        .priv_data_size = sizeof(RKMPPDecodeContext), \
        .init           = rkmpp_init_decoder, \
        .close          = rkmpp_close_decoder, \
        FF_CODEC_RECEIVE_FRAME_CB(rkmpp_receive_frame), \
        .flush          = rkmpp_flush, \
        .p.priv_class   = &rkmpp_##NAME##_dec_class, \
        .p.capabilities = AV_CODEC_CAP_DELAY | AV_CODEC_CAP_AVOID_PROBING | AV_CODEC_CAP_HARDWARE, \
        .hw_configs     = rkmpp_hw_configs, \
        .bsfs           = BSFS, \
        .p.wrapper_name = "rkmpp", \
        .caps_internal  = FF_CODEC_CAP_INIT_CLEANUP | FF_CODEC_CAP_NOT_INIT_THREADSAFE, \
    };

RKMPP_DEC(h264,  AV_CODEC_ID_H264,          "h264_mp4toannexb")
RKMPP_DEC(hevc,  AV_CODEC_ID_HEVC,          "hevc_mp4toannexb")
RKMPP_DEC(vp8,   AV_CODEC_ID_VP8,           NULL)
RKMPP_DEC(vp9,   AV_CODEC_ID_VP9,           NULL)