/*****************************************************************************
 * vaapi.c: VAAPI helpers for the libavcodec decoder
 *****************************************************************************
 * Copyright (C) 2017 VLC authors and VideoLAN
 * Copyright (C) 2009-2010 Laurent Aimar
 * Copyright (C) 2012-2014 Rémi Denis-Courmont
 *
 * Authors: Laurent Aimar <fenrir_AT_ videolan _DOT_ org>
 *
 * This program 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.
 *
 * This program 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 this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
 *****************************************************************************/

#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

#include <assert.h>

#include <vlc_common.h>
#include <vlc_plugin.h>
#include <vlc_fourcc.h>
#include <vlc_picture.h>
#include <vlc_picture_pool.h>

#ifdef VLC_VA_BACKEND_DRM
# include <sys/types.h>
# include <sys/stat.h>
# include <fcntl.h>
# include <vlc_fs.h>
# include <va/va_drm.h>
#endif
#include <libavcodec/avcodec.h>
#if FF_API_STRUCT_VAAPI_CONTEXT
#include <libavcodec/vaapi.h>
#else
#include <libavutil/hwcontext_vaapi.h>
#endif

#include "avcodec.h"
#include "va.h"
#include "../../hw/vaapi/vlc_vaapi.h"

#if !FF_API_STRUCT_VAAPI_CONTEXT
struct vaapi_context
{
    VADisplay display;
    VAConfigID config_id;
    VAContextID context_id;
};
#endif

struct vlc_va_sys_t
{
    struct vlc_vaapi_instance *va_inst;
    struct vaapi_context hw_ctx;

#ifdef VLC_VA_BACKEND_DRM
    picture_pool_t *pool;
#endif
};

static int GetVaProfile(AVCodecContext *ctx, const es_format_t *fmt,
                        VAProfile *va_profile, int *vlc_chroma,
                        unsigned *pic_count)
{
    VAProfile i_profile;
    unsigned count = 3;
    int i_vlc_chroma = VLC_CODEC_VAAPI_420;

    switch(ctx->codec_id)
    {
    case AV_CODEC_ID_MPEG1VIDEO:
    case AV_CODEC_ID_MPEG2VIDEO:
        i_profile = VAProfileMPEG2Main;
        count = 4;
        break;
    case AV_CODEC_ID_MPEG4:
        i_profile = VAProfileMPEG4AdvancedSimple;
        break;
    case AV_CODEC_ID_WMV3:
        i_profile = VAProfileVC1Main;
        break;
    case AV_CODEC_ID_VC1:
        i_profile = VAProfileVC1Advanced;
        break;
    case AV_CODEC_ID_H264:
        i_profile = VAProfileH264High;
        count = 18;
        break;
    case AV_CODEC_ID_HEVC:
        if (ctx->profile == AVPROFILE(HEVC_MAIN))
            i_profile = VAProfileHEVCMain;
        else if (ctx->profile == AVPROFILE(HEVC_MAIN_10))
        {
            i_profile = VAProfileHEVCMain10;
            i_vlc_chroma = VLC_CODEC_VAAPI_420_10BPP;
        }
        else
            return VLC_EGENERIC;
        count = 18;
        break;
    case AV_CODEC_ID_VP8:
        i_profile = VAProfileVP8Version0_3;
        count = 5;
        break;
    case AV_CODEC_ID_VP9:
        if (ctx->profile == AVPROFILE(VP9_0))
            i_profile = VAProfileVP9Profile0;
#if VA_CHECK_VERSION( 0, 39, 0 )
        else if (ctx->profile == AVPROFILE(VP9_2))
        {
            i_profile = VAProfileVP9Profile2;
            i_vlc_chroma = VLC_CODEC_VAAPI_420_10BPP;
        }
#endif
        else
            return VLC_EGENERIC;
        count = 10;
        break;
    default:
        return VLC_EGENERIC;
    }

    *va_profile = i_profile;
    *pic_count = count + ctx->thread_count;
    *vlc_chroma = i_vlc_chroma;
    return VLC_SUCCESS;
}

#ifndef VLC_VA_BACKEND_DRM

static int Get(vlc_va_t *va, picture_t *pic, uint8_t **data)
{
    (void) va;

    vlc_vaapi_PicAttachContext(pic);
    *data = (void *) (uintptr_t) vlc_vaapi_PicGetSurface(pic);

    return VLC_SUCCESS;
}

static void Delete(vlc_va_t *va, void **hwctx)
{
    vlc_va_sys_t *sys = va->sys;
    vlc_object_t *o = VLC_OBJECT(va);

    (void) hwctx;

    if (sys->hw_ctx.context_id != VA_INVALID_ID)
        vlc_vaapi_DestroyContext(o, sys->hw_ctx.display, sys->hw_ctx.context_id);
    if (sys->hw_ctx.config_id != VA_INVALID_ID)
        vlc_vaapi_DestroyConfig(o, sys->hw_ctx.display, sys->hw_ctx.config_id);
    vlc_vaapi_ReleaseInstance(sys->va_inst);
    free(sys);
}

static int Create(vlc_va_t *va, AVCodecContext *ctx, const AVPixFmtDescriptor *desc,
                  enum PixelFormat pix_fmt,
                  const es_format_t *fmt, picture_sys_t *p_sys)
{
    VLC_UNUSED(desc);
    if (pix_fmt != AV_PIX_FMT_VAAPI || p_sys == NULL)
        return VLC_EGENERIC;

    (void) fmt;
    vlc_object_t *o = VLC_OBJECT(va);

    int ret = VLC_EGENERIC;
    vlc_va_sys_t *sys = NULL;

    /* The picture must be allocated by the vout */
    VADisplay va_dpy;
    struct vlc_vaapi_instance *va_inst =
        vlc_vaapi_PicSysHoldInstance(p_sys, &va_dpy);

    VASurfaceID *render_targets;
    unsigned num_render_targets =
        vlc_vaapi_PicSysGetRenderTargets(p_sys, &render_targets);
    if (num_render_targets == 0)
        goto error;

    VAProfile i_profile;
    unsigned count;
    int i_vlc_chroma;
    if (GetVaProfile(ctx, fmt, &i_profile, &i_vlc_chroma, &count) != VLC_SUCCESS)
        goto error;

    sys = malloc(sizeof *sys);
    if (unlikely(sys == NULL))
    {
        ret = VLC_ENOMEM;
        goto error;
    }
    memset(sys, 0, sizeof (*sys));

    /* */
    sys->va_inst = va_inst;
    sys->hw_ctx.display = va_dpy;
    sys->hw_ctx.config_id = VA_INVALID_ID;
    sys->hw_ctx.context_id = VA_INVALID_ID;

#if FF_API_STRUCT_VAAPI_CONTEXT
    sys->hw_ctx.config_id =
        vlc_vaapi_CreateConfigChecked(o, sys->hw_ctx.display, i_profile,
                                      VAEntrypointVLD, i_vlc_chroma);
    if (sys->hw_ctx.config_id == VA_INVALID_ID)
        goto error;

    /* Create a context */
    sys->hw_ctx.context_id =
        vlc_vaapi_CreateContext(o, sys->hw_ctx.display, sys->hw_ctx.config_id,
                                ctx->coded_width, ctx->coded_height, VA_PROGRESSIVE,
                                render_targets, num_render_targets);
    if (sys->hw_ctx.context_id == VA_INVALID_ID)
        goto error;

    ctx->hwaccel_context = &sys->hw_ctx;
#else
    AVBufferRef *hwdev_ref = av_hwdevice_ctx_alloc(AV_HWDEVICE_TYPE_VAAPI);
    if (hwdev_ref == NULL)
        goto error;

    AVHWDeviceContext *hwdev_ctx = (void *) hwdev_ref->data;
    AVVAAPIDeviceContext *vadev_ctx = hwdev_ctx->hwctx;
    vadev_ctx->display = va_dpy;

    if (av_hwdevice_ctx_init(hwdev_ref) < 0)
    {
        av_buffer_unref(&hwdev_ref);
        goto error;
    }

    ctx->hw_device_ctx = hwdev_ref;
#endif

    va->sys = sys;
    va->description = vaQueryVendorString(sys->hw_ctx.display);
    va->get = Get;
    return VLC_SUCCESS;

error:
    if (sys != NULL)
    {
        if (sys->hw_ctx.context_id != VA_INVALID_ID)
            vlc_vaapi_DestroyContext(o, sys->hw_ctx.display, sys->hw_ctx.context_id);
        if (sys->hw_ctx.config_id != VA_INVALID_ID)
            vlc_vaapi_DestroyConfig(o, sys->hw_ctx.display, sys->hw_ctx.config_id);
        free(sys);
    }
    vlc_vaapi_ReleaseInstance(va_inst);
    return ret;
}

#else /* DRM */

static int GetDRM(vlc_va_t *va, picture_t *pic, uint8_t **data)
{
    vlc_va_sys_t *sys = va->sys;

    picture_t *vapic = picture_pool_Wait(sys->pool);
    if (vapic == NULL)
        return VLC_EGENERIC;
    vlc_vaapi_PicAttachContext(vapic);

    pic->context = vapic->context->copy(vapic->context);
    picture_Release(vapic);
    if (pic->context == NULL)
        return VLC_EGENERIC;

    *data = (void *)(uintptr_t)vlc_vaapi_PicGetSurface(pic);
    return VLC_SUCCESS;
}

static void DeleteDRM(vlc_va_t *va, void **hwctx)
{
    vlc_va_sys_t *sys = va->sys;
    vlc_object_t *o = VLC_OBJECT(va);

    (void) hwctx;
    picture_pool_Release(sys->pool);
    vlc_vaapi_DestroyContext(o, sys->hw_ctx.display, sys->hw_ctx.context_id);
    vlc_vaapi_DestroyConfig(o, sys->hw_ctx.display, sys->hw_ctx.config_id);
    vlc_vaapi_ReleaseInstance(sys->va_inst);
    free(sys);
}

static int CreateDRM(vlc_va_t *va, AVCodecContext *ctx, enum PixelFormat pix_fmt,
                     const es_format_t *fmt, picture_sys_t *p_sys)
{
    if (pix_fmt != AV_PIX_FMT_VAAPI || p_sys)
        return VLC_EGENERIC;

    (void) fmt;
    (void) p_sys;
    vlc_object_t *o = VLC_OBJECT(va);

    VAProfile i_profile;
    unsigned count;
    int i_vlc_chroma;
    if (GetVaProfile(ctx, fmt, &i_profile, &i_vlc_chroma, &count) != VLC_SUCCESS)
        return VLC_EGENERIC;

    vlc_va_sys_t *sys;

    sys = malloc(sizeof(vlc_va_sys_t));
    if (!sys)
       return VLC_ENOMEM;
    memset(sys, 0, sizeof (*sys));

    /* */
    sys->hw_ctx.display = NULL;
    sys->hw_ctx.config_id = VA_INVALID_ID;
    sys->hw_ctx.context_id = VA_INVALID_ID;
    sys->pool = NULL;
    sys->va_inst = NULL;

    /* Create a VA display */
    sys->va_inst = vlc_vaapi_InitializeInstanceDRM(o, vaGetDisplayDRM,
                                                   &sys->hw_ctx.display, NULL);
    if (!sys->va_inst)
        goto error;

    sys->hw_ctx.config_id =
        vlc_vaapi_CreateConfigChecked(o, sys->hw_ctx.display, i_profile,
                                      VAEntrypointVLD, 0);
    if (sys->hw_ctx.config_id == VA_INVALID_ID)
        goto error;

    /* Create surfaces */
    assert(ctx->coded_width > 0 && ctx->coded_height > 0);
    video_format_t vfmt = {
        .i_chroma = i_vlc_chroma,
        .i_width = ctx->coded_width,
        .i_height = ctx->coded_height,
        .i_visible_width = ctx->coded_width,
        .i_visible_height = ctx->coded_height
    };

    VASurfaceID *surfaces;
    sys->pool = vlc_vaapi_PoolNew(o, sys->va_inst, sys->hw_ctx.display, count,
                                  &surfaces, &vfmt, false);

    if (!sys->pool)
        goto error;

    /* Create a context */
    sys->hw_ctx.context_id =
        vlc_vaapi_CreateContext(o, sys->hw_ctx.display, sys->hw_ctx.config_id,
                                ctx->coded_width, ctx->coded_height,
                                VA_PROGRESSIVE, surfaces, count);
    if (sys->hw_ctx.context_id == VA_INVALID_ID)
        goto error;

    ctx->hwaccel_context = &sys->hw_ctx;
    va->sys = sys;
    va->description = vaQueryVendorString(sys->hw_ctx.display);
    va->get = GetDRM;
    return VLC_SUCCESS;

error:
    if (sys->hw_ctx.context_id != VA_INVALID_ID)
        vlc_vaapi_DestroyContext(o, sys->hw_ctx.display, sys->hw_ctx.context_id);
    if (sys->pool != NULL)
        picture_pool_Release(sys->pool);
    if (sys->hw_ctx.config_id != VA_INVALID_ID)
        vlc_vaapi_DestroyConfig(o, sys->hw_ctx.display, sys->hw_ctx.config_id);
    if (sys->va_inst != NULL)
        vlc_vaapi_ReleaseInstance(sys->va_inst);
    free(sys);
    return VLC_EGENERIC;
}
#endif

vlc_module_begin ()
#ifdef VLC_VA_BACKEND_DRM
    set_description( N_("VA-API video decoder via DRM") )
    set_capability( "hw decoder", 0 )
    set_callbacks( CreateDRM, DeleteDRM )
    add_shortcut( "vaapi", "vaapi_drm" )
#else
    set_description( N_("VA-API video decoder") )
    set_capability( "hw decoder", 100 )
    set_callbacks( Create, Delete )
    add_shortcut( "vaapi" )
#endif
    set_category( CAT_INPUT )
    set_subcategory( SUBCAT_INPUT_VCODEC )
vlc_module_end ()