#!/bin/bash
# C1 + C2 + C6 instrumentation: per-codec decode with strace (ioctl) + lsof (fds) + dmesg before/after.
# Decodes 30 frames into a tmp file to verify HW engagement; doesn't measure FPS.
set -u
OUT=$HOME/measurements/p3
mkdir -p $OUT
codecs=("h264:rkvdec:h264.mp4" "vp8:hantro:vp8.webm" "mpeg2:hantro:mpeg2.ts")

# C6 pre: dmesg snapshot
sudo dmesg --time-format=ctime > $OUT/dmesg.pre.txt

for spec in "${codecs[@]}"; do
  codec=${spec%%:*}; route=$(echo $spec | cut -d: -f2); ext=${spec##*:}
  cf=$HOME/measurements/encoded/bbb_60s_720p.${ext}
  log=$OUT/engage_${codec}
  rm -f $log.{strace,lsof,stderr,nv12} 2>/dev/null

  echo "=== $codec ($route) ===" | tee $log.summary

  # Launch in background, track PID; lsof+strace alongside
  LIBVA_DRIVER_NAME=v4l2_request strace -ff -o $log.strace -e trace=ioctl,openat \
      ffmpeg -hide_banner -loglevel error \
      -hwaccel vaapi -hwaccel_output_format vaapi \
      -i "$cf" -vf "hwdownload,format=nv12" -frames:v 30 \
      -f rawvideo -pix_fmt nv12 -y $log.nv12 \
      > $log.stderr 2>&1 &
  pid=$!

  # Wait briefly then lsof
  sleep 0.6
  if kill -0 $pid 2>/dev/null; then
    lsof -p $pid 2>/dev/null | grep -E "/dev/(video|media|dri)" > $log.lsof
  fi
  wait $pid; rc=$?

  # Aggregate
  size=$(stat -c%s $log.nv12 2>/dev/null || echo 0)
  expected=$((30 * 1280 * 720 * 3 / 2))  # 30 frames yuv420p 720p
  size_ok=$([ "$size" = "$expected" ] && echo "ok" || echo "MISMATCH (expected=$expected)")

  vidioc=$(grep -h "VIDIOC_S_EXT_CTRLS\|VIDIOC_QUERYCAP\|VIDIOC_QBUF\|VIDIOC_DQBUF" $log.strace.* 2>/dev/null | wc -l)
  media_q=$(grep -h "MEDIA_REQUEST_IOC_QUEUE\|MEDIA_REQUEST_IOC_REINIT" $log.strace.* 2>/dev/null | wc -l)
  fd_count=$(wc -l < $log.lsof 2>/dev/null || echo 0)

  {
    echo "  rc=$rc  size=$size  size_ok=$size_ok"
    echo "  ioctl V4L2 (S_EXT_CTRLS+Q/DQBUF+QUERYCAP)=$vidioc"
    echo "  ioctl MEDIA_REQUEST_*=$media_q"
    echo "  open V4L2/media/DRI fds=$fd_count"
    if [ -s $log.lsof ]; then
      echo "  fds:"
      awk '{print "    " $9}' $log.lsof | sort -u
    fi
  } | tee -a $log.summary
done

# C6 post
sudo dmesg --time-format=ctime > $OUT/dmesg.post.txt
echo
echo "=== dmesg diff (new lines since pre) ==="
diff $OUT/dmesg.pre.txt $OUT/dmesg.post.txt | head -20

echo "=== done $(date -Iseconds) ==="