#!/usr/bin/env bash

WORK_TIME=1200
PAUSE_TIME=300

timer_state_pid=0
timer_state_state="inactive"
timer_state_time="00:00"
timer_state_progress=100

sub_timer_pid=0

start_timer() {
    timer_type=$1
    duration=0

    timer_state_state="$timer_type" # Update done later

    if [ "$timer_type" = "work" ]; then
        duration=$WORK_TIME
        timer_type="pause"
    elif [ "$timer_type" = "pause" ]; then
        duration=$PAUSE_TIME
        timer_type="work"
    else
        echo "Invalid argument"
        exit 1
    fi

    for ((i=duration; i>=0; i--)); do
        timer_state_progress=$((i * 100 / duration))
        timer_state_time="$(date -u -d @$i +'%M:%S')"
        update_timer_state
        sleep 1
    done

    start_timer "$timer_type"
}

update_timer_state() {
    echo "{\"pid\": $timer_state_pid, \"state\": \"$timer_state_state\", \"time\": \"$timer_state_time\", \"progress\": $timer_state_progress}"
}

handle_signal() {
    # If a timer is running, kill it
    if [ $sub_timer_pid -ne 0 ]; then
        kill -9 $sub_timer_pid
        sub_timer_pid=0
        timer_state_state="inactive"
        timer_state_progress=100
        update_timer_state
    else
        start_timer "work" &
        sub_timer_pid=$!
        # Will wait forever
        wait $sub_timer_pid
    fi
}

# Set up the signal handler
trap handle_signal SIGUSR1

timer_state_pid=$$; update_timer_state

while true; do
    sleep infinity &
    wait
done