#!/bin/bash

BASENAME=tmp
ITER=1
A_ITER=1
B_ITER=1
FRAMES=200
POSITIONAL=()
while [[ $# -gt 0 ]]
do
key="$1"

case $key in
    -f|--frames)
    FRAMES=$(expr $2 + 0)
    shift # past argument
    shift # past value
    ;;
    -s|--start)
    ITER=$(expr $2 + 1)
    shift # past argument
    shift # past value
    ;;
    -o|--output)
    OUTPUT_DIR="$2"
    BASENAME=$(basename $OUTPUT_DIR)
    shift # past argument
    shift # past value
    ;;
    # --default)
    # DEFAULT=YES
    # shift # past argument
    # ;;
    *)    # unknown option
    POSITIONAL+=("$1") # save it in an array for later
    shift # past argument
    ;;
esac
done
set -- "${POSITIONAL[@]}" # restore positional parameters

rm -rf tmp/
mkdir tmp/

A_DIR="wah"

for B_DIR in "${POSITIONAL[@]}"
do

  if [ ! -d "$B_DIR" ]
  then
    echo "${B_DIR}: not a directory.."
    continue
  fi

  if [ "$A_DIR" = "wah" ]
  then
    echo "${B_DIR}: starting iteration..."
    A_DIR=$B_DIR
    A_ITER=$B_ITER
    continue
  fi

  a=$(printf "%s/frame_%05d.png" $A_DIR $A_ITER)
  b=$(printf "%s/frame_%05d.png" $B_DIR $((B_ITER + FRAMES)))

  echo "A: $a"
  echo "B: $b"

  convert -verbose "$a" PNG24:tmp_normalized_0.png
  convert -verbose "$b" PNG24:tmp_normalized_1.png

  ./makeOptFlow.sh tmp_normalized_%01d.png flow 0

  STEP=$(bc -l <<< "1 / $FRAMES")
  SEQUENCE=`seq 0.0 $STEP 1.0`

  for scale in $SEQUENCE; do
    scale="${scale/,/.}"
    echo "${ITER}: ${scale}"
    a_f=$(printf "%s/frame_%05d.png" $A_DIR $A_ITER)
    b_f=$(printf "%s/frame_%05d.png" $B_DIR $B_ITER)
    th torch_warp.lua \
      -flow_file flow/backward_1_0.flo \
      -source_image $a_f \
      -output_image warp_0.png \
      -scale $scale
    th torch_warp.lua \
      -flow_file flow/forward_0_1.flo \
      -source_image $b_f \
      -output_image warp_1.png \
      -scale $(bc <<< "1.0-$scale")
    OUT=$(printf "tmp/frame_%05d.png" $ITER)
    convert warp_0.png warp_1.png -compose blend -define compose:args=$(bc <<< "100*$scale/1") -composite $OUT
    rm warp_0.png warp_1.png

    ITER=$((ITER+1))
    A_ITER=$((A_ITER+1))
    B_ITER=$((B_ITER+1))
  done

  A_DIR=$B_DIR
  A_ITER=$B_ITER

  rm -rf flow/ tmp_normalized*.png
done

ffmpeg -i tmp/frame_%05d.png -vcodec libx264 -pix_fmt yuv420p -profile:v baseline -level 3 "mixed_${BASENAME}.mp4"

cd tmp/
mkdir 256
for i in *; do convert $i -resize '256x256!' 256/$i; done
cd ..
mv tmp mixed_${BASENAME}