/*
  * VDA HW acceleration.
  *
  * copyright (c) 2011 Sebastien Zwickert
  *
  * 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 <pthread.h>
 #include <CoreFoundation/CFDictionary.h>
 #include <CoreFoundation/CFNumber.h>
 #include <CoreFoundation/CFData.h>
 #include <CoreFoundation/CFString.h>
 

 #include "libavutil/avutil.h"

 #include "vda_internal.h"
 
 /* Helper to create a dictionary according to the given pts. */
 static CFDictionaryRef vda_dictionary_with_pts(int64_t i_pts)
 {
     CFStringRef key = CFSTR("FF_VDA_DECODER_PTS_KEY");
     CFNumberRef value = CFNumberCreate(kCFAllocatorDefault, kCFNumberSInt64Type, &i_pts);

     CFDictionaryRef user_info = CFDictionaryCreate(kCFAllocatorDefault,
                                                    (const void **)&key,
                                                    (const void **)&value,
                                                    1,
                                                    &kCFTypeDictionaryKeyCallBacks,
                                                    &kCFTypeDictionaryValueCallBacks);

     CFRelease(value);
     return user_info;
 }
 
 /* Helper to retrieve the pts from the given dictionary. */
 static int64_t vda_pts_from_dictionary(CFDictionaryRef user_info)
 {
     CFNumberRef pts;
     int64_t outValue = 0;
 

     if (!user_info)

         return 0;
 
     pts = CFDictionaryGetValue(user_info, CFSTR("FF_VDA_DECODER_PTS_KEY"));
 
     if (pts)
         CFNumberGetValue(pts, kCFNumberSInt64Type, &outValue);
 
     return outValue;
 }
 
 /* Removes and releases all frames from the queue. */
 static void vda_clear_queue(struct vda_context *vda_ctx)
 {
     vda_frame *top_frame;
 

     pthread_mutex_lock(&vda_ctx->queue_mutex);

     while (vda_ctx->queue) {

         top_frame = vda_ctx->queue;
         vda_ctx->queue = top_frame->next_frame;
         ff_vda_release_vda_frame(top_frame);
     }
 

     pthread_mutex_unlock(&vda_ctx->queue_mutex);

 }
 
 
 /* Decoder callback that adds the vda frame to the queue in display order. */
 static void vda_decoder_callback (void *vda_hw_ctx,
                                   CFDictionaryRef user_info,
                                   OSStatus status,
                                   uint32_t infoFlags,
                                   CVImageBufferRef image_buffer)
 {
     struct vda_context *vda_ctx = (struct vda_context*)vda_hw_ctx;
     vda_frame *new_frame;
     vda_frame *queue_walker;
 

     if (!image_buffer)

         return;
 

     if (vda_ctx->cv_pix_fmt_type != CVPixelBufferGetPixelFormatType(image_buffer))

         return;
 

     new_frame = av_mallocz(sizeof(vda_frame));

     if (!new_frame)
         return;
 

     new_frame->next_frame = NULL;
     new_frame->cv_buffer = CVPixelBufferRetain(image_buffer);
     new_frame->pts = vda_pts_from_dictionary(user_info);
 

     pthread_mutex_lock(&vda_ctx->queue_mutex);

 
     queue_walker = vda_ctx->queue;
 

     if (!queue_walker || (new_frame->pts < queue_walker->pts)) {

         /* we have an empty queue, or this frame earlier than the current queue head */
         new_frame->next_frame = queue_walker;
         vda_ctx->queue = new_frame;

     } else {

         /* walk the queue and insert this frame where it belongs in display order */
         vda_frame *next_frame;
 

         while (1) {

             next_frame = queue_walker->next_frame;
 

             if (!next_frame || (new_frame->pts < next_frame->pts)) {

                 new_frame->next_frame = next_frame;
                 queue_walker->next_frame = new_frame;
                 break;
             }
             queue_walker = next_frame;
         }
     }
 

     pthread_mutex_unlock(&vda_ctx->queue_mutex);

 }
 
 int ff_vda_create_decoder(struct vda_context *vda_ctx,
                           uint8_t *extradata,
                           int extradata_size)
 {
     OSStatus status = kVDADecoderNoErr;
     CFNumberRef height;
     CFNumberRef width;
     CFNumberRef format;
     CFDataRef avc_data;
     CFMutableDictionaryRef config_info;

     CFMutableDictionaryRef buffer_attributes;
     CFMutableDictionaryRef io_surface_properties;
     CFNumberRef cv_pix_fmt;

     vda_ctx->bitstream = NULL;
     vda_ctx->ref_size = 0;
 

     pthread_mutex_init(&vda_ctx->queue_mutex, NULL);

     /* Each VCL NAL in the bistream sent to the decoder
      * is preceeded by a 4 bytes length header.
      * Change the avcC atom header if needed, to signal headers of 4 bytes. */
     if (extradata_size >= 4 && (extradata[4] & 0x03) != 0x03) {
         uint8_t *rw_extradata;
 
         if (!(rw_extradata = av_malloc(extradata_size)))
             return AVERROR(ENOMEM);
 
         memcpy(rw_extradata, extradata, extradata_size);
 
         rw_extradata[4] |= 0x03;
 
         avc_data = CFDataCreate(kCFAllocatorDefault, rw_extradata, extradata_size);
 
         av_freep(&rw_extradata);
     } else {
         avc_data = CFDataCreate(kCFAllocatorDefault, extradata, extradata_size);
     }
 

     config_info = CFDictionaryCreateMutable(kCFAllocatorDefault,
                                             4,
                                             &kCFTypeDictionaryKeyCallBacks,
                                             &kCFTypeDictionaryValueCallBacks);

     height   = CFNumberCreate(kCFAllocatorDefault, kCFNumberSInt32Type, &vda_ctx->height);
     width    = CFNumberCreate(kCFAllocatorDefault, kCFNumberSInt32Type, &vda_ctx->width);
     format   = CFNumberCreate(kCFAllocatorDefault, kCFNumberSInt32Type, &vda_ctx->format);

 
     CFDictionarySetValue(config_info, kVDADecoderConfiguration_Height, height);
     CFDictionarySetValue(config_info, kVDADecoderConfiguration_Width, width);
     CFDictionarySetValue(config_info, kVDADecoderConfiguration_SourceFormat, format);
     CFDictionarySetValue(config_info, kVDADecoderConfiguration_avcCData, avc_data);
 

     buffer_attributes = CFDictionaryCreateMutable(kCFAllocatorDefault,
                                                   2,
                                                   &kCFTypeDictionaryKeyCallBacks,
                                                   &kCFTypeDictionaryValueCallBacks);
     io_surface_properties = CFDictionaryCreateMutable(kCFAllocatorDefault,
                                                       0,
                                                       &kCFTypeDictionaryKeyCallBacks,
                                                       &kCFTypeDictionaryValueCallBacks);

     cv_pix_fmt  = CFNumberCreate(kCFAllocatorDefault,
                                  kCFNumberSInt32Type,
                                  &vda_ctx->cv_pix_fmt_type);
     CFDictionarySetValue(buffer_attributes,
                          kCVPixelBufferPixelFormatTypeKey,
                          cv_pix_fmt);
     CFDictionarySetValue(buffer_attributes,
                          kCVPixelBufferIOSurfacePropertiesKey,
                          io_surface_properties);
 

     status = VDADecoderCreate(config_info,
                               buffer_attributes,
                               (VDADecoderOutputCallback *)vda_decoder_callback,
                               vda_ctx,
                               &vda_ctx->decoder);

 
     CFRelease(height);
     CFRelease(width);
     CFRelease(format);
     CFRelease(avc_data);
     CFRelease(config_info);

     CFRelease(io_surface_properties);
     CFRelease(cv_pix_fmt);
     CFRelease(buffer_attributes);

 
     if (kVDADecoderNoErr != status)
         return status;
 
     return 0;
 }
 
 int ff_vda_destroy_decoder(struct vda_context *vda_ctx)
 {
     OSStatus status = kVDADecoderNoErr;
 
     if (vda_ctx->decoder)
         status = VDADecoderDestroy(vda_ctx->decoder);
 
     vda_clear_queue(vda_ctx);
 

     pthread_mutex_destroy(&vda_ctx->queue_mutex);

     if (vda_ctx->bitstream)
         av_freep(&vda_ctx->bitstream);
 

     if (kVDADecoderNoErr != status)
         return status;
 
     return 0;
 }
 
 vda_frame *ff_vda_queue_pop(struct vda_context *vda_ctx)
 {
     vda_frame *top_frame;
 
     if (!vda_ctx->queue)
         return NULL;
 

     pthread_mutex_lock(&vda_ctx->queue_mutex);

     top_frame = vda_ctx->queue;
     vda_ctx->queue = top_frame->next_frame;

     pthread_mutex_unlock(&vda_ctx->queue_mutex);

 
     return top_frame;
 }
 
 void ff_vda_release_vda_frame(vda_frame *frame)
 {

     if (frame) {

         CVPixelBufferRelease(frame->cv_buffer);
         av_freep(&frame);
     }
 }
 
 int ff_vda_decoder_decode(struct vda_context *vda_ctx,
                           uint8_t *bitstream,
                           int bitstream_size,
                           int64_t frame_pts)
 {
     OSStatus status = kVDADecoderNoErr;
     CFDictionaryRef user_info;
     CFDataRef coded_frame;
 
     coded_frame = CFDataCreate(kCFAllocatorDefault, bitstream, bitstream_size);
     user_info = vda_dictionary_with_pts(frame_pts);
 
     status = VDADecoderDecode(vda_ctx->decoder, 0, coded_frame, user_info);
 
     CFRelease(user_info);
     CFRelease(coded_frame);
 
     if (kVDADecoderNoErr != status)
         return status;
 
     return 0;
 }