#!/bin/sh
# shellcheck disable=SC1090,SC1091,SC2154

# SC1090 & SC2154
# The files sourced are user generated files that should contain the needed
# variables for the script to function correctly. It should be safe to ignore
# these warnings.

# Required Commands
# ffmpeg - needed for aud
# grim - needed for pic
# mkdir - create missing directories
# pactl - create loopback devices for multi-device audio recording in wf-recorder
# slurp - make a selection
# wf-recorder - needed for rec
# wl-copy - copy images to clipboard

# This script is intended for use on wayland; however, `scr aud` should work fine without
# wayland.

# Set required variables if needed
[ "$SCR_CFG_DIR" ] || SCR_CFG_DIR="${XDG_CONFIG_HOME:-$HOME/.config}/scr"
[ "$SCR_CACHE_DIR" ] || SCR_CACHE_DIR="${XDG_CACHE_HOME:-$HOME/.cache}/scr"

# Source the configuration file
# A sample configuration can be found in my dotfiles at:
# https://github.com/yemouu/setup/blob/master/home/cfg/scr/config.sh
# TODO: put an example cofiguration in this repo
. "$SCR_CFG_DIR/config.sh" || {
	printf '%s\n' "${0##*/}: failed to source $SCR_CFG_DIR/config.sh" 1>&2; exit 1
}

# Usage statement for the script
usage() {
	printf '%b\n' "usage: ${0##*/} action [options]" \
	              "actions:" \
	              "\taud - audio" \
	              "\tpic - picture" \
	              "\trec - record" \
	              "options:" \
	              "\t-a - record desktop audio (aud,rec)" \
	              "\t-c - copy image to clipboard (pic)" \
	              "\t-h - display this message" \
	              "\t-m - record microphone audio (aud,rec)" \
	              "\t-o - output to use (pic,rec)" \
	              "\t-d - all displays (pic)"
}

# Determine the action to run
case $1 in
	aud      ) action="scr_aud" ;;
	pic      ) action="scr_pic" ;;
	rec      ) action="scr_rec" ;;
	*h|*help ) usage; exit 0 ;;
	*        ) printf '%s\n' "${0##*/}: $1: invalid action" 1>&2; usage 1>&2; exit 1 ;;
esac
shift

# Determine options to run with based on arguments
# (I need to stop)
for flag in "$@"
do
	# Make sure arguments start with '-' and are atleast 2 characters long
	case $flag in
		-  ) continue ;;
		-- ) break ;;
		-* ) ;;
		*  ) continue;;
	esac

	# Split arguments to be 1 character long and determine options to use
	args=${flag#-}

	while [ "$args" ]
	do
		a=${args%"${args#?}"}

		case $a in
			a ) desktop_audio=true ;;
			c ) copy_clipboard=true ;;
			d ) output=all ;; # Kinda redundent lol
			h ) usage; exit 0 ;;
			m ) microphone=true ;;
			o ) aargs=$*
			    output=${aargs##*"${flag}"}; output=${output#\ }; output=${output%%\ *}
			    [ "${output}" ] || printf '%s\n' "${0##*/}: -o: missing output" 1>&2 ;;
			* ) printf '%s\n' "${0##*/}: -$a: invalid argument" 1>&2
			    usage 1>&2; exit 1 ;;
		esac

		args=${args#?}
	done
done
unset args arg

# Simple function to print out an error message and exit
die() {
	printf '%s\n' "${0##*/}: $*" 1>&2
	exit 1
}

# Record Audio
scr_aud() {
	# Create the directory to store audio recordings if it does not already exist
	[ -d "$scr_aud_dir" ] || \
		{ mkdir -p "$scr_aud_dir" || die "failed to make directory: $scr_aud_dir"; }

	# Create the directory to store logs if it does not already exist
	[ -d "$SCR_CACHE_DIR" ] || \
		{ mkdir -p "$SCR_CACHE_DIR" || \
		  die "failed to make directory: $SCR_CACHE_DIR"; }

	filename="$scr_aud_dir/$aud_filename"

	# Require atleast one of the arguments: -a or -m
	[ "$microphone" ] || [ "$desktop_audio" ] || \
		{ die "aud: argument -a or -m is required to record audio"; }

	# Set ffmpeg options based on script options
	[ "$microphone" ] && { args="-f pulse -i $aud_source"; }
	[ "$desktop_audio" ] && { args="$args -f pulse -i $aud_sink"; }
	[ "$microphone" ] && [ "$desktop_audio" ] && \
		{ args="$args -filter_complex amix=inputs=2"; }

	# Pressing Ctrl+C will exit the script instead of just ffmpeg.
	# Intercept Ctrl+C and do nothing.
	trap '' INT

	# shellcheck disable=SC2086
	# Word splitting is favorable here
	ffmpeg $args "$filename" > "$SCR_CACHE_DIR/aud.log" 2>&1 &
	aud_pid=$!
	printf '%s' "Press Ctrl+C to stop recording. " 1>&2
	wait $aud_pid

	# Reset the trap
	trap - INT

	printf '\n%s\n' "$filename"
}

# Take a screenshot
scr_pic() {
	# Create directories if they do not already exist
	[ -d "$scr_pic_dir" ] || \
		{ mkdir -p "$scr_pic_dir" || die "failed to make directory: $scr_pic_dir"; }

	[ -d "$SCR_CACHE_DIR" ] || \
		{ mkdir -p "$SCR_CACHE_DIR" || \
		  die "failed to create directory: $SCR_CACHE_DIR"; }

	filename="$scr_pic_dir/$pic_filename"

	if [ "$output" = "all" ]
	then
		# Grim will screenshot all monitors by default
		grim "$filename" > "$SCR_CACHE_DIR/pic.log" 2>&1
	else
		# Get the geometry of the screenshot from the user and take the screenshot
		# shellcheck disable=SC2086
		if [ "$output" ]; then set -- -o "$output"; else set -- -g "$(slurp ${SLURP_ARGS})"; fi
		grim "$@" "$filename" > "$SCR_CACHE_DIR/pic.log" 2>&1
	fi

	# Copy the image to the system clipboard
	$copy_clipboard && { wl-copy  <"$filename" > "$SCR_CACHE_DIR/copy.log" 2>&1; }
	
	printf '%s\n' "$filename"
}

scr_rec() {
	# Create directories if they do not already exist
	[ -d "$scr_rec_dir" ] || \
		{ mkdir -p "$scr_rec_dir" || die "failed to make directory: $scr_pic_dir"; }

	[ -d "$SCR_CACHE_DIR" ] || \
		{ mkdir -p "$SCR_CACHE_DIR" || \
		  die "failed to make directory: $SCR_CACHE_DIR"; }

	filename="$scr_rec_dir/$rec_filename"

	# Set wf-recorder arguments based on script options
	[ "$microphone" ] && args="-a$aud_source"
	[ "$desktop_audio" ] && args="-a$aud_sink"

	# If both microphone and desktop_audio is set, create a loopback devices pointing to
	# scr_inputs. wf-record does not support multiple audio devices. This is how they
	# recomend you record two devices at the same time.
	[ "$microphone" ] && [ "$desktop_audio" ] && {
		unload_pulse_modules=true
		null_sink=$(pactl load-module module-null-sink sink_name=aud_both)
		lb_desk=$(pactl load-module module-loopback sink=aud_both source="$aud_sink")
		lb_mic=$(pactl load-module module-loopback sink=aud_both source="$aud_source")
		args="-aaud_both.monitor"
	}

	# Pressing Ctrl+C will exit the script instead of just wf-recorder.
	# Intercept Ctrl+C and exit wf-recorder instead of the script
	trap '' INT

	# shellcheck disable=SC2086
	if [ "$output" ]; then set -- -o "$output"; else set -- -g "$(slurp ${SLURP_ARGS})"; fi
	# Word splitting is favorable here
	# shellcheck disable=SC2086
	wf-recorder $args $rec_extraflags "$@" -f "$filename" > "$SCR_CACHE_DIR/rec.log" 2>&1 &
	rec_pid=$!
	printf '%s' "Press Ctrl+C to stop recording. " 1>&2
	wait $rec_pid

	# Reset the trap
	trap - INT

	# Clean up pulseaudio modules that the script created
	[ "$unload_pulse_modules" ] && {
		pactl unload-module "$lb_mic"
		pactl unload-module "$lb_desk"
		pactl unload-module "$null_sink"
	}

	printf '\n%s\n' "$filename"
}

$action

# Run post scripts
# Scripts in the directory `$SCR_CFG_DIR/scripts` will
# take in `$action` as `$1` and `$filename` as `$2`.
# Sample scripts can be found in my dotfiles at:
# https://github.com/yemouu/setup/blob/master/home/cfg/scr/scripts
for i in "$SCR_CFG_DIR/scripts/"*
do
	[ -x "$i" ] && {
		printf '%s\n' "# $i --- START" >> "$SCR_CACHE_DIR/scripts.log"
		$i "$action" "$filename" > "$SCR_CACHE_DIR/scripts.log" 2>&1
		printf '%s\n' "# $i --- END" >> "$SCR_CACHE_DIR/scripts.log"
	}
done