#!/bin/bash
# Iterates through the list of available sinks from pactl
# Made to be used with a hotkey to quickly swap between outputs. Therefore takes no inputs.

# Function takes the sink that we are making default and moves all inputs to that sink
function change_sink_inputs_to_default_sink_num {
	readarray -t all_sink_inputs <<<"$(pacmd list-sink-inputs | grep index:)"
	for sink_input in "${all_sink_inputs[@]}"
	do
		sink_input_arr=( $sink_input )
		index_num=${sink_input_arr[1]}  # index 0 of the array should be "index:" and next the number we want
		pactl move-sink-input $index_num $1  
		echo "Moved sink input $index_num to sink $1"
	done
}


# Get current default sink. Iterate through list to find the one that comes next
# 	Set the 1st sink in the list to default after loop ends without exiting
default_sink_line=$(pactl list short sinks | grep $(pactl get-default-sink))
default_sink_arr=( $default_sink_line )
default_sink_num=${default_sink_arr[0]} # The number of the currently default sink. Not using the whole line because they can change frequently

readarray -t sink_names <<<"$(pactl list short sinks)"
last_sink_active=false
for sink_name in "${sink_names[@]}"
do
	sink_arr=( $sink_name )
	sink_num=${sink_arr[0]}
	if [ "$last_sink_active" = true ]; then
		pactl set-default-sink $sink_num
		echo "Set pulse default sink to number $sink_num"
		change_sink_inputs_to_default_sink_num "$sink_num"	
		exit 0
	fi
	if [ "$default_sink_num" = "$sink_num" ]; then
		last_sink_active=true
	fi
done
# If never got to 1 past the currently active sink in the loop, sets sink to first in the list
first_sink=${sink_names[0]}
first_sink_arr=( $first_sink )
first_sink_num=${first_sink_arr[0]}
pactl set-default-sink $first_sink_num
echo "Set pulse default sink to number $first_sink_num"
change_sink_inputs_to_default_sink_num "$first_sink_num"
exit 0