#!/bin/sh

## Set this values on new system!
##########################################
NOTE_NAME="eDP1"
DPI="96"
##########################################

## Settings
SAVEPATH="/tmp/wpos"
LAST_FILE="LAST"
PROG_PATH="$(dirname "$0")"

## Init
COMMAND="$1"
EXT1_NAME="none"
EXT2_NAME="none"
EXT1_STATUS="disconnected"
EXT2_STATUS="disconnected"

## Query current settings
XRANDR="$(xrandr -q)"

## Some functions
get_resolution() {
	grep -A1 "^$1\s*connected" | tail -n1 | awk '{ print $1 }'
}

detect_status() {
	sed -n -e "s/^$1\s*\([a-z]*\)\s*.*$/\1/p"
}

detect_connected() {
	sed -n -e 's/^\([A-Za-z0-9-]*\)\s*connected.*$/\1/p'
}

detect_all() {
	sed -n -e 's/^\([A-Za-z0-9-]*\)\s*\(dis\)*connected.*$/\1/p'
}

detect_active() {
	grep -A1 "^$1\s*connected" | tail -n1 | awk '{ print $2 }' | grep '\*'
}

off_except() {
	OFF_STRING=""
	for device in $(echo "$XRANDR" | detect_all); do
		for ignore in $@ ; do
			[ "$device" = "$ignore" ] && continue 2
		done
		OFF_STRING="$OFF_STRING --output $device --off"
	done
	echo "$OFF_STRING"
}

handle_non_exist_mode() {
	xrandr --dpi "$DPI" $(off_except "$1" "$2") --output $2 --mode $4 --output $1 --mode $3 --left-of $2
}

compute_hash() {
	INPUT="$1"

	NOTE_ACTIVE="$(echo "$INPUT" | detect_active "$NOTE_NAME")"
	HASH_DATA="${NOTE_NAME}${NOTE_STATUS}${NOTE_MAX}${NOTE_ACTIVE}"
	if [ -n "$EXT1_NAME" ]; then
		EXT1_ACTIVE="$(echo "$INPUT" | detect_active "$EXT1_NAME")"
		HASH_DATA="${HASH_DATA}${EXT1_NAME}${EXT1_STATUS}${EXT1_MAX}${EXT1_ACTIVE}"
	fi
	if [ -n "$EXT2_NAME" ]; then
		EXT2_ACTIVE="$(echo "$INPUT" | detect_active "$EXT2_NAME")"
		HASH_DATA="${HASH_DATA}${EXT2_NAME}${EXT2_STATUS}${EXT2_MAX}${EXT2_ACTIVE}"
	fi
	echo "$HASH_DATA" | sha1sum | awk '{ print $1 }'
}

## Get notebook display status
NOTE_STATUS="$(echo "$XRANDR" | detect_status "$NOTE_NAME")"

## Try to detect some external displays and theirs resolution
EXT1_NAME="$(echo "$XRANDR" | grep -v "$NOTE_NAME" | detect_connected | head -n 1)"
if [ -n "$EXT1_NAME" ]; then
	EXT1_STATUS="$(echo "$XRANDR" | detect_status "$EXT1_NAME")"
	EXT2_NAME="$(echo "$XRANDR" | grep -v "\($NOTE_NAME\|$EXT1_NAME\)" | detect_connected | head -n 1)"
	[ -n "$EXT2_NAME" ] && EXT2_STATUS="$(echo "$XRANDR" | detect_status "$EXT2_NAME")"
fi
NOTE_MAX="$(echo "$XRANDR" | get_resolution "$NOTE_NAME")"
EXT1_MAX="$(echo "$XRANDR" | get_resolution "$EXT1_NAME")"
EXT2_MAX="$(echo "$XRANDR" | get_resolution "$EXT2_NAME")"

## Save windows' positions before autodetection
[ ! -d "$SAVEPATH" ] && mkdir -p "$SAVEPATH"
if [ -f "$SAVEPATH"/"$LAST_FILE" ]; then
	"$PROG_PATH"/wpos.sh save "$(cat "$SAVEPATH"/"$LAST_FILE")"
fi

## Main "profiles" logic
## Start with some special command
if [ "$COMMAND" = "profile" ]; then
	HASH="$(compute_hash "$XRANDR")"
	echo "$HASH"
	exit 0

## And "regular" display setting commands
elif [ "$COMMAND" = "external" -a "$EXT1_STATUS" = "connected" ]; then
	xrandr --dpi "$DPI" $(off_except "$EXT1_NAME") --output "$EXT1_NAME" --mode "$EXT1_MAX"

elif [ "$COMMAND" = "external2" -a "$EXT2_STATUS" = "connected" ]; then
	xrandr --dpi "$DPI" $(off_except "$EXT2_NAME") --output "$EXT2_NAME" --mode "$EXT2_MAX"

elif [ "$COMMAND" = "mirror" -a "$NOTE_STATUS" = "connected" -a "$EXT1_STATUS" = "connected" ]; then
	if [ "$(echo "$NOTE_MAX" | cut -dx -f1)" -le "$(echo "$EXT1_MAX" | cut -dx -f1)" ]; then
		MUTUAL_RESOLUTION="$NOTE_MAX"
	else
		MUTUAL_RESOLUTION="$EXT1_MAX"
	fi
	xrandr --dpi "$DPI" $(off_except "$NOTE_NAME"  "$EXT1_NAME") \
	--output "$NOTE_NAME" --mode "$MUTUAL_RESOLUTION" \
	--output "$EXT1_NAME" --mode "$MUTUAL_RESOLUTION" --same-as "$NOTE_NAME"

elif [ "$COMMAND" = "2external" -a "$EXT1_STATUS" = "connected" -a "$EXT2_STATUS" = "connected" ]; then
	handle_non_exist_mode "$EXT2_NAME" "$EXT1_NAME" "$EXT2_MAX" "$EXT1_MAX"

elif [ "$COMMAND" = "note" -a "$NOTE_STATUS" = "connected" ]; then
	xrandr --dpi "$DPI" $(off_except "$NOTE_NAME") --output "$NOTE_NAME" --mode "$NOTE_MAX"

elif [ "$EXT1_STATUS" = "connected" -a "$NOTE_STATUS" = "connected" -a "$EXT2_STATUS" = "disconnected" ]; then
	handle_non_exist_mode "$EXT1_NAME" "$NOTE_NAME" "$EXT1_MAX" "$NOTE_MAX"

elif [ "$EXT1_STATUS" = "connected" -a "$NOTE_STATUS" = "connected" -a "$EXT2_STATUS" = "connected" ]; then
	# This isn't one command, because there is some weird error in xrandr.
	# That is the only way that this thing works.
	xrandr --dpi "$DPI" $(off_except "$NOTE_NAME" "$EXT1_NAME" "$EXT2_NAME")
	xrandr --dpi "$DPI" --output "$NOTE_NAME" --mode "$NOTE_MAX"
	xrandr --dpi "$DPI" --output "$EXT1_NAME" --mode "$EXT1_MAX" --left-of "$NOTE_NAME"
	xrandr --dpi "$DPI" --output "$EXT2_NAME" --mode "$EXT2_MAX" --left-of "$EXT1_NAME"

elif [ "$EXT2_STATUS" = "disconnected" -a "$NOTE_STATUS" = "connected" -a "$EXT1_STATUS" = "disconnected" ]; then
	xrandr --dpi "$DPI" $(off_except "$NOTE_NAME") --output "$NOTE_NAME" --mode "$NOTE_MAX"

fi

## Query current status
XRANDR="$(xrandr -q)"
HASH="$(compute_hash "$XRANDR")"

## Update LAST
echo "$HASH" > "$SAVEPATH"/"$LAST_FILE"

## Restore known profile
if [ -f "$SAVEPATH"/"$HASH" ]; then
	"$PROG_PATH"/wpos.sh restore "$HASH"
fi