#!/bin/sh

# Usage:
# `$0`: Ask for recording type via dmenu
# `$0 screencast`: Record both audio and screen
# `$0 video`: Record only screen
# `$0 audio`: Record only audio
# `$0 kill`: Kill existing recording
#
# If there is already a running instance, user will be prompted to end it.

killrecording() {
	recpid="$(cat /tmp/recordingpid)"
	# kill with SIGTERM, allowing finishing touches.
	kill -15 "$recpid"
	rm -f /tmp/recordingpid
	# even after SIGTERM, ffmpeg may still run, so SIGKILL it.
	sleep 3
	kill -9 "$recpid"
	exit
	}

screencast() { \
	ffmpeg -y \
	-thread_queue_size 4096 \
	-f x11grab \
	-framerate 60 \
	-s "$(xdpyinfo | grep dimensions | awk '{print $2;}')" \
	-i "$DISPLAY" \
	-f alsa -ac 2 -i pulse \
	-r 30 \
 	-c:v libx264rgb -crf 0 -preset ultrafast -c:a flac \
	"$HOME/Videos/Screen/$(date '+%y%m%d-%H%M-%S').mkv" &
	echo $! > /tmp/recordingpid
    }

jacka() { \
	ffmpeg -y \
	-thread_queue_size 4096 \
	-f jack -i jack_out.monitor \
	-ac 2 -channel_layout stereo -async 1 \
	-c:a flac "$HOME/Videos/Tape/$(date '+%y%m%d-%H%M-%S').flac"
	echo $! > /tmp/recordingpid
}

jackv() {
	ffmpeg -y \
	-thread_queue_size 4096 \
	-f jack -i ffmpeg \
	-f x11grab \
	-framerate 60 \
	-s "$(xdpyinfo | grep dimensions | awk '{print $2;}')" \
	-i "$DISPLAY" \
	-r 30 \
	-c:v libx264 -qp 0 -r 30 -c:a flac \
	"$HOME/Videos/Screen/$(date '+%y%m%d-%H%M-%S').mkv" &
	echo $! > /tmp/recordingpid
}

mute() {
	ffmpeg -y \
	-f x11grab \
	-thread_queue_size 4096 \
	-s "$(xdpyinfo | grep dimensions | awk '{print $2;}')" \
	-i "$DISPLAY" \
 	-c:v libx264 -qp 0 -r 30 \
	"$HOME/Videos/$(date '+%y%m%d-%H%M-%S').mkv" &
	echo $! > /tmp/recordingpid
	}

audio() { \
	ffmpeg -y \
	-thread_queue_size 4096 \
	-f pulse -i default \
	-ac 2 -channel_layout stereo -async 1 \
	-c:a flac \
	"$HOME/Music/Tape/$(date '+%y%m%d-%H%M-%S').mp3" &
	echo $! > /tmp/recordingpid
	}

askrecording() { \
	choice=$(printf "screencast\\nvideo\\naudio\\njack video\\njack audio" | dmenu -i -p "Select recording style ")
	case "$choice" in
		screencast) screencast;;
		video) mute;;
		audio) audio;;
		"jack video") jackv;;
		"jack audio") jacka;;
	esac
	}

asktoend() { \
	response=$(printf "No\\nYes" | dmenu -i -p "Recording still active. End recording? ") &&
	[ "$response" = "Yes" ] &&  killrecording
	}

case "$1" in
	screencast) screencast;;
	video) mute;;
	audio) audio;;
	"jack video") jackv;;
	"jack audio") jacka;;
	kill) killrecording;;
	*) ([ -f /tmp/recordingpid ] && asktoend && exit) || askrecording;;
esac