setCovers

#!/bin/bash
# For each immediate subdirectory, attempts to set poster.jpg as folder icon
# Usage setSubdirIcons [-f] /path/to/folder

usage() {					# print usage message & terminate
	echo "Usage: ${0} [-f] directory" 1>&2
	echo "Attemps to set each subdirectory's \"poster.jpg\" as its icon"
	echo "Use -f flag to overwrite existing folder icons"
	exit 1
}

CMDS="realpath basename dirname"
for i in $CMDS; do
    # command -v will return >0 when the $i is not found
	command -v "$i" >/dev/null && continue || { echo "command '$i' not found."; exit 1; }
done

# ImageMagick v7 uses the `magick` command; v6 uses `identify`/`convert` directly.
if command -v magick >/dev/null ; then
	IM_IDENTIFY=(magick identify)
	IM_CONVERT=(magick)
else
	for i in identify convert; do
		command -v "$i" >/dev/null && continue || { echo "command '$i' not found."; exit 1; }
	done
	IM_IDENTIFY=(identify)
	IM_CONVERT=(convert)
fi

# Process arguments
force=false
if [ $# -eq 0 ] ; then usage ; fi		# no arguments ?
if [ "$1" == "-f" ] ; then				# -f flag?
	force=true
	shift
fi
if [ $# -ne 1 ] ; then
	echo "Wrong number of arguments" 1>&2
	usage
fi
DIR="$1"

# Script constants
SCRIPTPATH=$(realpath "$0")
SCRIPTNAME=$(basename "$SCRIPTPATH")
SCRIPTFOLDER=$(dirname "$SCRIPTPATH")

# File output constants
SETICONPATH="$SCRIPTFOLDER/setIcon.py"
LOG="$SCRIPTPATH-$(date +%F_%Hh%M).log"

# Prefer a local virtualenv interpreter when present.
PYTHON_CMD=(python3)
if [ -x "$SCRIPTFOLDER/.venv/bin/python" ] ; then
	PYTHON_CMD=("$SCRIPTFOLDER/.venv/bin/python")
fi

if ! "${PYTHON_CMD[@]}" -c "import AppKit" >/dev/null 2>&1 ; then
	echo "Python module 'AppKit' not found for: ${PYTHON_CMD[0]}" 1>&2
	echo "Install it with: ${PYTHON_CMD[0]} -m pip install pyobjc" 1>&2
	exit 1
fi

# Counters
success=0
prevsuccess=0
failure=0

echo "Firing up the flux capacitor..."
echo -e "$SCRIPTNAME $DIR \n" > "$LOG"

for subdir in "$DIR"/*/ ; do
	folderJPG="$subdir""poster.jpg"
	if [ -e "$folderJPG" ] ; then			#not case-sensitive
		echo $subdir | tee -a "$LOG"
		squarePNG="${folderJPG%.*}.png"
		squareICNS="${folderJPG%.*}.icns"

		# Get height and width
		oldW=`"${IM_IDENTIFY[@]}" -format "%w" "$folderJPG"`
		oldH=`"${IM_IDENTIFY[@]}" -format "%h" "$folderJPG"`
		echo -en "\tposter.jpg [${oldW}x${oldH}]" | tee -a "$LOG"

		# Skip if icon is already set
		if [ $force == "false" ] && [ -e "$subdir"/Icon$'\r' ] ; then
			echo " -> icon previously set" ℹ️ | tee -a "$LOG"
			prevsuccess=$((prevsuccess+1))
			continue
		fi

		# Calculate new square size
		p2=`"${IM_IDENTIFY[@]}" -format "%[fx:2^(ceil(log(max(w,h))/log(2)))]" "$folderJPG"`

		# Convert to square png
		# Note: two-step conversion needed to avoid vertical black bars on either side
		"${IM_CONVERT[@]}" "$folderJPG" -resize ${p2}x${p2} -background transparent \
			-gravity center -extent ${p2}x${p2} "$squarePNG"

		# Convert square png to square icns
		"${IM_CONVERT[@]}" "$squarePNG" "$squareICNS"
		echo -n " -> folder.icns [${p2}x${p2}]..." | tee -a "$LOG"

		# Call python3 script setIcon
		"${PYTHON_CMD[@]}" "$SETICONPATH" "$squareICNS" "$subdir"
		if [ ${?} -eq 0 ] ; then
			echo "applied succesfully! ✅" | tee -a "$LOG"
			success=$((success+1))
		else
			echo "unable to set file icon ❌" | tee -a "$LOG"
			failure=$((failure+1))
		fi

		# Clean up
		rm -f "$squarePNG" "$squareICNS"
	else
		echo "$folderJPG does not exist ❌" | tee -a "$LOG"
		failure=$((failure+1))
	fi
done

echo -e "\n ✅  $success \t ❌  $failure \t ℹ️  $prevsuccess \t\t Total: $((success+failure+prevsuccess))" | tee -a "$LOG"