/*

  * 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 <string.h>
 
 #include <va/va.h>
 #include <va/va_vpp.h>
 
 #include "libavutil/avassert.h"
 #include "libavutil/hwcontext.h"
 #include "libavutil/hwcontext_vaapi.h"
 #include "libavutil/mem.h"
 #include "libavutil/opt.h"
 #include "libavutil/pixdesc.h"
 
 #include "avfilter.h"
 #include "formats.h"
 #include "internal.h"

 #include "scale.h"

 #include "video.h"

 
 typedef struct ScaleVAAPIContext {
     const AVClass *class;
 
     AVVAAPIDeviceContext *hwctx;
     AVBufferRef *device_ref;
 
     int valid_ids;
     VAConfigID  va_config;
     VAContextID va_context;
 
     AVBufferRef       *input_frames_ref;
     AVHWFramesContext *input_frames;
 
     AVBufferRef       *output_frames_ref;
     AVHWFramesContext *output_frames;
 
     char *output_format_string;
     enum AVPixelFormat output_format;
 

     char *w_expr;      // width expression string
     char *h_expr;      // height expression string
 
     int output_width;  // computed width
     int output_height; // computed height

 } ScaleVAAPIContext;
 
 
 static int scale_vaapi_query_formats(AVFilterContext *avctx)
 {
     enum AVPixelFormat pix_fmts[] = {
         AV_PIX_FMT_VAAPI, AV_PIX_FMT_NONE,
     };

     int err;
 
     if ((err = ff_formats_ref(ff_make_format_list(pix_fmts),
                               &avctx->inputs[0]->out_formats)) < 0)
         return err;
     if ((err = ff_formats_ref(ff_make_format_list(pix_fmts),
                               &avctx->outputs[0]->in_formats)) < 0)
         return err;

 
     return 0;
 }
 
 static int scale_vaapi_pipeline_uninit(ScaleVAAPIContext *ctx)
 {
     if (ctx->va_context != VA_INVALID_ID) {
         vaDestroyContext(ctx->hwctx->display, ctx->va_context);
         ctx->va_context = VA_INVALID_ID;
     }
 
     if (ctx->va_config != VA_INVALID_ID) {
         vaDestroyConfig(ctx->hwctx->display, ctx->va_config);
         ctx->va_config = VA_INVALID_ID;
     }
 
     av_buffer_unref(&ctx->output_frames_ref);
     av_buffer_unref(&ctx->device_ref);
     ctx->hwctx = 0;
 
     return 0;
 }
 
 static int scale_vaapi_config_input(AVFilterLink *inlink)
 {
     AVFilterContext *avctx = inlink->dst;
     ScaleVAAPIContext *ctx = avctx->priv;
 
     scale_vaapi_pipeline_uninit(ctx);
 
     if (!inlink->hw_frames_ctx) {
         av_log(avctx, AV_LOG_ERROR, "A hardware frames reference is "
                "required to associate the processing device.\n");
         return AVERROR(EINVAL);
     }
 
     ctx->input_frames_ref = av_buffer_ref(inlink->hw_frames_ctx);
     ctx->input_frames = (AVHWFramesContext*)ctx->input_frames_ref->data;
 
     return 0;
 }
 
 static int scale_vaapi_config_output(AVFilterLink *outlink)
 {

     AVFilterLink *inlink = outlink->src->inputs[0];

     AVFilterContext *avctx = outlink->src;
     ScaleVAAPIContext *ctx = avctx->priv;
     AVVAAPIHWConfig *hwconfig = NULL;
     AVHWFramesConstraints *constraints = NULL;
     AVVAAPIFramesContext *va_frames;
     VAStatus vas;
     int err, i;
 
     scale_vaapi_pipeline_uninit(ctx);
 
     ctx->device_ref = av_buffer_ref(ctx->input_frames->device_ref);
     ctx->hwctx = ((AVHWDeviceContext*)ctx->device_ref->data)->hwctx;
 
     av_assert0(ctx->va_config == VA_INVALID_ID);
     vas = vaCreateConfig(ctx->hwctx->display, VAProfileNone,
                          VAEntrypointVideoProc, 0, 0, &ctx->va_config);
     if (vas != VA_STATUS_SUCCESS) {
         av_log(ctx, AV_LOG_ERROR, "Failed to create processing pipeline "
                "config: %d (%s).\n", vas, vaErrorStr(vas));
         err = AVERROR(EIO);
         goto fail;
     }
 
     hwconfig = av_hwdevice_hwconfig_alloc(ctx->device_ref);
     if (!hwconfig) {
         err = AVERROR(ENOMEM);
         goto fail;
     }
     hwconfig->config_id = ctx->va_config;
 
     constraints = av_hwdevice_get_hwframe_constraints(ctx->device_ref,
                                                       hwconfig);
     if (!constraints) {
         err = AVERROR(ENOMEM);
         goto fail;
     }
 
     if (ctx->output_format == AV_PIX_FMT_NONE)
         ctx->output_format = ctx->input_frames->sw_format;
     if (constraints->valid_sw_formats) {
         for (i = 0; constraints->valid_sw_formats[i] != AV_PIX_FMT_NONE; i++) {
             if (ctx->output_format == constraints->valid_sw_formats[i])
                 break;
         }
         if (constraints->valid_sw_formats[i] == AV_PIX_FMT_NONE) {
             av_log(ctx, AV_LOG_ERROR, "Hardware does not support output "
                    "format %s.\n", av_get_pix_fmt_name(ctx->output_format));
             err = AVERROR(EINVAL);
             goto fail;
         }
     }
 

     if ((err = ff_scale_eval_dimensions(ctx,
                                         ctx->w_expr, ctx->h_expr,
                                         inlink, outlink,
                                         &ctx->output_width, &ctx->output_height)) < 0)
         goto fail;
 

     if (ctx->output_width  < constraints->min_width  ||
         ctx->output_height < constraints->min_height ||
         ctx->output_width  > constraints->max_width  ||
         ctx->output_height > constraints->max_height) {
         av_log(ctx, AV_LOG_ERROR, "Hardware does not support scaling to "
                "size %dx%d (constraints: width %d-%d height %d-%d).\n",
                ctx->output_width, ctx->output_height,
                constraints->min_width,  constraints->max_width,
                constraints->min_height, constraints->max_height);
         err = AVERROR(EINVAL);
         goto fail;
     }
 
     ctx->output_frames_ref = av_hwframe_ctx_alloc(ctx->device_ref);
     if (!ctx->output_frames_ref) {
         av_log(ctx, AV_LOG_ERROR, "Failed to create HW frame context "
                "for output.\n");
         err = AVERROR(ENOMEM);
         goto fail;
     }
 
     ctx->output_frames = (AVHWFramesContext*)ctx->output_frames_ref->data;
 
     ctx->output_frames->format    = AV_PIX_FMT_VAAPI;
     ctx->output_frames->sw_format = ctx->output_format;
     ctx->output_frames->width     = ctx->output_width;
     ctx->output_frames->height    = ctx->output_height;
 
     // The number of output frames we need is determined by what follows
     // the filter.  If it's an encoder with complex frame reference
     // structures then this could be very high.
     ctx->output_frames->initial_pool_size = 10;
 
     err = av_hwframe_ctx_init(ctx->output_frames_ref);
     if (err < 0) {
         av_log(ctx, AV_LOG_ERROR, "Failed to initialise VAAPI frame "
                "context for output: %d\n", err);
         goto fail;
     }
 
     va_frames = ctx->output_frames->hwctx;
 
     av_assert0(ctx->va_context == VA_INVALID_ID);
     vas = vaCreateContext(ctx->hwctx->display, ctx->va_config,
                           ctx->output_width, ctx->output_height,
                           VA_PROGRESSIVE,
                           va_frames->surface_ids, va_frames->nb_surfaces,
                           &ctx->va_context);
     if (vas != VA_STATUS_SUCCESS) {
         av_log(ctx, AV_LOG_ERROR, "Failed to create processing pipeline "
                "context: %d (%s).\n", vas, vaErrorStr(vas));
         return AVERROR(EIO);
     }
 
     outlink->w = ctx->output_width;
     outlink->h = ctx->output_height;
 
     outlink->hw_frames_ctx = av_buffer_ref(ctx->output_frames_ref);
     if (!outlink->hw_frames_ctx) {
         err = AVERROR(ENOMEM);
         goto fail;
     }
 
     av_freep(&hwconfig);
     av_hwframe_constraints_free(&constraints);
     return 0;
 
 fail:
     av_buffer_unref(&ctx->output_frames_ref);
     av_freep(&hwconfig);
     av_hwframe_constraints_free(&constraints);
     return err;
 }
 
 static int vaapi_proc_colour_standard(enum AVColorSpace av_cs)
 {
     switch(av_cs) {
 #define CS(av, va) case AVCOL_SPC_ ## av: return VAProcColorStandard ## va;
         CS(BT709,     BT709);
         CS(BT470BG,   BT601);
         CS(SMPTE170M, SMPTE170M);
         CS(SMPTE240M, SMPTE240M);
 #undef CS
     default:
         return VAProcColorStandardNone;
     }
 }
 
 static int scale_vaapi_filter_frame(AVFilterLink *inlink, AVFrame *input_frame)
 {
     AVFilterContext *avctx = inlink->dst;
     AVFilterLink *outlink = avctx->outputs[0];
     ScaleVAAPIContext *ctx = avctx->priv;
     AVFrame *output_frame = NULL;
     VASurfaceID input_surface, output_surface;
     VAProcPipelineParameterBuffer params;
     VABufferID params_id;

     VARectangle input_region;

     VAStatus vas;
     int err;
 
     av_log(ctx, AV_LOG_DEBUG, "Filter input: %s, %ux%u (%"PRId64").\n",
            av_get_pix_fmt_name(input_frame->format),
            input_frame->width, input_frame->height, input_frame->pts);
 
     if (ctx->va_context == VA_INVALID_ID)
         return AVERROR(EINVAL);
 
     input_surface = (VASurfaceID)(uintptr_t)input_frame->data[3];
     av_log(ctx, AV_LOG_DEBUG, "Using surface %#x for scale input.\n",
            input_surface);
 

     output_frame = ff_get_video_buffer(outlink, ctx->output_width,
                                        ctx->output_height);

     if (!output_frame) {
         err = AVERROR(ENOMEM);
         goto fail;
     }
 
     output_surface = (VASurfaceID)(uintptr_t)output_frame->data[3];
     av_log(ctx, AV_LOG_DEBUG, "Using surface %#x for scale output.\n",
            output_surface);
 
     memset(&params, 0, sizeof(params));
 

     // If there were top/left cropping, it could be taken into
     // account here.
     input_region = (VARectangle) {
         .x      = 0,
         .y      = 0,
         .width  = input_frame->width,
         .height = input_frame->height,
     };
 

     params.surface = input_surface;

     params.surface_region = &input_region;

     params.surface_color_standard =
         vaapi_proc_colour_standard(input_frame->colorspace);
 
     params.output_region = 0;
     params.output_background_color = 0xff000000;
     params.output_color_standard = params.surface_color_standard;
 
     params.pipeline_flags = 0;
     params.filter_flags = VA_FILTER_SCALING_HQ;
 
     vas = vaBeginPicture(ctx->hwctx->display,
                          ctx->va_context, output_surface);
     if (vas != VA_STATUS_SUCCESS) {
         av_log(ctx, AV_LOG_ERROR, "Failed to attach new picture: "
                "%d (%s).\n", vas, vaErrorStr(vas));
         err = AVERROR(EIO);
         goto fail;
     }
 
     vas = vaCreateBuffer(ctx->hwctx->display, ctx->va_context,
                          VAProcPipelineParameterBufferType,
                          sizeof(params), 1, &params, &params_id);
     if (vas != VA_STATUS_SUCCESS) {
         av_log(ctx, AV_LOG_ERROR, "Failed to create parameter buffer: "
                "%d (%s).\n", vas, vaErrorStr(vas));
         err = AVERROR(EIO);
         goto fail_after_begin;
     }
     av_log(ctx, AV_LOG_DEBUG, "Pipeline parameter buffer is %#x.\n",
            params_id);
 
     vas = vaRenderPicture(ctx->hwctx->display, ctx->va_context,
                           &params_id, 1);
     if (vas != VA_STATUS_SUCCESS) {
         av_log(ctx, AV_LOG_ERROR, "Failed to render parameter buffer: "
                "%d (%s).\n", vas, vaErrorStr(vas));
         err = AVERROR(EIO);
         goto fail_after_begin;
     }
 
     vas = vaEndPicture(ctx->hwctx->display, ctx->va_context);
     if (vas != VA_STATUS_SUCCESS) {
         av_log(ctx, AV_LOG_ERROR, "Failed to start picture processing: "
                "%d (%s).\n", vas, vaErrorStr(vas));
         err = AVERROR(EIO);
         goto fail_after_render;
     }
 

     if (CONFIG_VAAPI_1 || ctx->hwctx->driver_quirks &

         AV_VAAPI_DRIVER_QUIRK_RENDER_PARAM_BUFFERS) {
         vas = vaDestroyBuffer(ctx->hwctx->display, params_id);
         if (vas != VA_STATUS_SUCCESS) {
             av_log(ctx, AV_LOG_ERROR, "Failed to free parameter buffer: "
                    "%d (%s).\n", vas, vaErrorStr(vas));
             // And ignore.
         }

     }
 
     av_frame_copy_props(output_frame, input_frame);
     av_frame_free(&input_frame);
 
     av_log(ctx, AV_LOG_DEBUG, "Filter output: %s, %ux%u (%"PRId64").\n",
            av_get_pix_fmt_name(output_frame->format),
            output_frame->width, output_frame->height, output_frame->pts);
 
     return ff_filter_frame(outlink, output_frame);
 
     // We want to make sure that if vaBeginPicture has been called, we also
     // call vaRenderPicture and vaEndPicture.  These calls may well fail or
     // do something else nasty, but once we're in this failure case there
     // isn't much else we can do.
 fail_after_begin:
     vaRenderPicture(ctx->hwctx->display, ctx->va_context, &params_id, 1);
 fail_after_render:
     vaEndPicture(ctx->hwctx->display, ctx->va_context);
 fail:
     av_frame_free(&input_frame);
     av_frame_free(&output_frame);
     return err;
 }
 
 static av_cold int scale_vaapi_init(AVFilterContext *avctx)
 {
     ScaleVAAPIContext *ctx = avctx->priv;
 
     ctx->va_config  = VA_INVALID_ID;
     ctx->va_context = VA_INVALID_ID;
     ctx->valid_ids  = 1;
 
     if (ctx->output_format_string) {
         ctx->output_format = av_get_pix_fmt(ctx->output_format_string);
         if (ctx->output_format == AV_PIX_FMT_NONE) {
             av_log(ctx, AV_LOG_ERROR, "Invalid output format.\n");
             return AVERROR(EINVAL);
         }
     } else {
         // Use the input format once that is configured.
         ctx->output_format = AV_PIX_FMT_NONE;
     }
 
     return 0;
 }
 
 static av_cold void scale_vaapi_uninit(AVFilterContext *avctx)
 {
     ScaleVAAPIContext *ctx = avctx->priv;
 
     if (ctx->valid_ids)
         scale_vaapi_pipeline_uninit(ctx);
 
     av_buffer_unref(&ctx->input_frames_ref);
     av_buffer_unref(&ctx->output_frames_ref);
     av_buffer_unref(&ctx->device_ref);
 }
 
 
 #define OFFSET(x) offsetof(ScaleVAAPIContext, x)

 #define FLAGS (AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM)

 static const AVOption scale_vaapi_options[] = {
     { "w", "Output video width",

       OFFSET(w_expr), AV_OPT_TYPE_STRING, {.str = "iw"}, .flags = FLAGS },

     { "h", "Output video height",

       OFFSET(h_expr), AV_OPT_TYPE_STRING, {.str = "ih"}, .flags = FLAGS },

     { "format", "Output video format (software format of hardware frames)",
       OFFSET(output_format_string), AV_OPT_TYPE_STRING, .flags = FLAGS },
     { NULL },
 };
 
 static const AVClass scale_vaapi_class = {
     .class_name = "scale_vaapi",
     .item_name  = av_default_item_name,
     .option     = scale_vaapi_options,
     .version    = LIBAVUTIL_VERSION_INT,
 };
 
 static const AVFilterPad scale_vaapi_inputs[] = {
     {
         .name         = "default",
         .type         = AVMEDIA_TYPE_VIDEO,
         .filter_frame = &scale_vaapi_filter_frame,
         .config_props = &scale_vaapi_config_input,
     },
     { NULL }
 };
 
 static const AVFilterPad scale_vaapi_outputs[] = {
     {
         .name = "default",
         .type = AVMEDIA_TYPE_VIDEO,
         .config_props = &scale_vaapi_config_output,
     },
     { NULL }
 };
 
 AVFilter ff_vf_scale_vaapi = {
     .name          = "scale_vaapi",
     .description   = NULL_IF_CONFIG_SMALL("Scale to/from VAAPI surfaces."),
     .priv_size     = sizeof(ScaleVAAPIContext),
     .init          = &scale_vaapi_init,
     .uninit        = &scale_vaapi_uninit,
     .query_formats = &scale_vaapi_query_formats,
     .inputs        = scale_vaapi_inputs,
     .outputs       = scale_vaapi_outputs,
     .priv_class    = &scale_vaapi_class,

     .flags_internal = FF_FILTER_FLAG_HWFRAME_AWARE,

 };