#!/bin/bash

#set -e

if [[ "${1}" == "" ]]; then
	echo "Please provide a template JSON"
fi

if [[ "${2}" == "" ]]; then
	echo "Please provide one video or directory of images"
	exit 2
fi

if [[ "${3}" == "" ]]; then
	echo "Please an output directory for pages"
	exit 3
fi

if [ ! -d "${3}" ]; then
	echo "${3} output directory does not exist"
	exit 4
fi

if [ -f "${2}" ]; then
	echo "Exporting frames from ${2}..."
	OUTPUT=$(mktemp -d)
	ffmpeg -y -re -i "${2}" \
		-q:v 1 -qmin 1 -qmax 1 \
		"${OUTPUT}/frame_%06d.tif"
else
	if [ -d "${2}" ]; then
		OUTPUT="${2}"
	else
		echo "Argument ${2} is neither video nor directory"
		exit 43
	fi
fi

tiff_name () {
	filename=$(basename "${1}")
	filename="${filename%.*}"
	echo "${filename}.tif"
}

echo "Using frames in ${OUTPUT}..."

W=$(cat "${1}" | jq -r ".width")
H=$(cat "${1}" | jq -r ".height")
DPI=$(echo "${W}/8.5" | bc)
FRAMES=$(mktemp)

echo "DPI: $DPI"

ls -1 "${OUTPUT}"*.{jpg,jpeg,JPG,JPG,png,PNG,gif,GIF,tif,tiff,TIF,TIFF} > "${FRAMES}" 2> /dev/null
FC=$(wc -l < "${FRAMES}")
PAGES=$(echo "(${FC}/4)+1" | bc)

TMP=$(mktemp -d)

for ((i=0;i<${PAGES};++i)); do
	f1=$(sed -n "$(((i*4)+1))p" < "${FRAMES}")
	f2=$(sed -n "$(((i*4)+2))p" < "${FRAMES}")
	f3=$(sed -n "$(((i*4)+3))p" < "${FRAMES}")
	f4=$(sed -n "$(((i*4)+4))p" < "${FRAMES}")
	args=""
	if [[ "${f1}" != "" ]]; then
		name=$(tiff_name "${f1}")
		dest="${TMP}/${name}"
		bash white_fourcell.sh $DPI "${f1}" "${dest}"
		args="${args} ${dest}"
	else 
		continue 
	fi
	if [[ "${f2}" != "" ]]; then
		name=$(tiff_name "${f2}")
		dest="${TMP}/${name}"
		bash white_fourcell.sh $DPI "${f2}" "${dest}"
		args="${args} ${dest}"
	fi
	if [[ "${f3}" != "" ]]; then
		name=$(tiff_name "${f3}")
		dest="${TMP}/${name}"
		bash white_fourcell.sh $DPI "${f3}" "${dest}"
		args="${args} ${dest}"
	fi
	if [[ "${f4}" != "" ]]; then
		name=$(tiff_name "${f4}")
		dest="${TMP}/${name}"
		bash white_fourcell.sh $DPI "${f4}" "${dest}"
		args="${args} ${dest}"
	fi
	bash apply_image.sh ${3}/page_$i.tiff "${1}" ${args}
done

echo "Wrote ${3}/page_$i.tiff"

# x determine dpi
# convert frame to white_fourcell

rm "${FRAMES}"
rm -rf "${TMP}"