#!/bin/bash

# beepmein

# A little wrapper around linux 'at' command, that will beep you at specific time, see --help.
# On Debian systems make sure 'at' is installed with --no-install-recommends.

# Copyright (C) 2019/2020 brontosaurusrex
# License: GPLv3 or later.

# superecho
superecho () {
    local msg="$1"
    if [[ -t 0 ]] ; then
        echo "$msg"
    else
        notify-send -t 3500 "$msg"
    fi
}

# prepare config dir
config="$HOME/.cache/beepmein"
mkdir -p "$config" || superecho "$config not found, warning."

# var
delay="0"

# softlinks to audio samples
alarmSample="$config/alarm"     # longer sample
reminderSample="$config/remind" # shorter sample

# Will kill all children with 'killall beepmein'
trap 'kill $(jobs -p) >/dev/null 2>&1' EXIT

# required
command -v at >/dev/null 2>&1 || { >&2 echo "I need at: sudo apt install --no-install-recommends at" ; exit 1; }
command -v speaker-test >/dev/null 2>&1 || { >&2 echo "I need speaker-test from alsa-utils (for reminder sound)." ; exit 1; }
command -v notify-send >/dev/null 2>&1 || { >&2 echo "I need notify-send." ; exit 1; }

# help
help () { 
cat << EOF
beepmein help

    Set reminder or alarm:

        beepmein now + 3 minutes # reminder ('at' time format)
        beepmein 22:10           # reminder ('at' time format)
        beepmein 3               # reminder (in 3 minutes, beepmein shortcut),
        beepmein 8:00 --alarm    # alarm (must be last parameter)
        beepmein --nr 5          # with no reason (must be first parameter)
           
    Set sounds: (playback depends on mpv or vlc)

        beepmein --set-alarm <path/to/alarm.sound>
        beepmein --set-remind <path/to/reminder.sound>

    Test playback, blinking and notifications:

        beepmein --reaction reminder_text
        beepmein --reaction --alarm alarm_text
        beepmein --test # test everything
        
    List jobs
    
        beepmein --list # or -l

    Kill all running playback/beeping:

        killall beepmein 

    Notes:

        at -l       # will list pending jobs (or atq)
        at -r <num> # will remove job <num>  (or atrm)

EOF
}

# reminder sound, needs speaker-test (alsa-utils)
beep () {
    local loops="$1"
    [[ -z "$loops" ]] && loops="1"
    for ((i=1; i<=loops; i++))
    do
        timeout -s HUP 0.2 speaker-test -t sine -f 1000 &>/dev/null
        sleep 0.2
    done
}

# $1 = how many times to blink, $2 = pause between each blink
blink () {
    # find primary connected or else 1st connected monitor
    monitor="$(xrandr -q | grep -w "connected" | grep "primary" | cut -f1 -d ' ')"
    if [[ -z "$monitor" ]]; then # no primary AND connected found, lets try 1st connected
        monitor="$(xrandr -q | grep -w "connected" | cut -f1 -d ' ')"
    fi 
    [[ -z "$monitor" ]] && { >&2 echo "No monitors found error" ; exit 1; }
    
    # find current brightness of that monitor
    now="$(xrandr --verbose | grep -A 15 "$monitor" | grep -i brightness | cut -f2 -d ' ')"
    [[ -z "$now" ]] && { >&2 echo "Could not get current brightness error" ;  exit 1; }
    
    local blinks="$1"
    [[ -z "$blinks" ]] && blinks="1"
    for ((c=1; c<=blinks; c++))
    do
        # blink up
        for i in $(seq "$now" 0.2 3.0); do     
            xrandr --output "$monitor" --brightness "$i"
            sleep 0.01
        done
        
        # blink down
        for i in $(seq 3.0 -0.2 "$now"); do     
            xrandr --output "$monitor" --brightness "$i"
            sleep 0.01
        done

    local pause="$2"
    [[ -z "$pause" ]] && pause="0.1"
    sleep "$pause"
    xrandr --output "$monitor" --brightness "$now"
    done
}

# alarm failsafe (by misko), this will be used if 'alarmSample' is not found.
alarmfailsafe () {
for ((i=1; i<=10; i++)); do
      for ((c=1;c<=3;c++)); do
          timeout -s HUP  0.2 speaker-test -t sine -f 3000  > /dev/null 2>&1
          sleep 0.2
       done
       sleep 1
done
}

# test alarm sample path (no test for reminder sample)
testAlarmPath () {
    [[ -f "$alarmSample" ]] || { >&2 superecho "Note: alarmSample $alarmSample not found, Internal fail-safe beep will be used instead."; }
}

# mpv or cvlc (by jr)
playa () {
    file="$1"
    [[ -f $file ]] || { return 1; } # if no sample configured then return error, so that failsafe beeps can be used instead
    if command -v mpv >/dev/null 2>&1
    then
        mpv --no-resume-playback --no-video "$file" >/dev/null 2>&1
    elif command -v cvlc >/dev/null 2>&1
    then
        cvlc --no-video "$file" vlc://quit >/dev/null 2>&1
    else
        superecho "no player"
        return 1
    fi
}

# test audio and notifications
test () {
    echo "notify test"
    notify-send "notify test" || echo "failed"
    echo
    echo "fail-safe internal beep test used for reminders"
    beep "3" || echo "failed"
    echo
    echo "mpv sample test used for alarms (either this or vlc must pass)"
    mpv --no-resume-playback --no-video --length=10 "$alarmSample" || echo "mpv failed"
    echo
    echo "vlc sample test used for alarms"
    cvlc --no-video --run-time=10 "$alarmSample" vlc://quit || echo "cvlc failed"
    echo
    echo "fail-safe internal beep test used for alarms"
    alarmfailsafe || echo "failed"
    echo
}

# validate 'at' time syntax by generating fake job
validate () {
tmpjob="$(at "$1" <<<"test" 2>&1 | grep ^job | cut -f2 -d ' ')"
if [[ -n "$tmpjob" ]]; then
    # job was generated ok
    atrm "$tmpjob"
else
    # error
    return 1
fi
}

# help or test
if [[ "$1" == "--help" ]] || [[ "$1" == "-h" ]] || [[ $# -eq 0 ]]; then
    help; exit
elif [[ "$1" == "--test" ]]; then
    test; exit
fi

# list all 'at' jobs, last non-empty line only
if [[ "$1" == "-l" ]] || [[ "$1" == "--list" ]]; then
    atq | sort -r | while read -r job rest ; do
        echo -n "$job $rest | "
        at -c "$job" | tac | grep -vm 1 '^[[:space:]]*$'
    done
    exit
fi

# --set-alarm (via softlink)
if [[ "$1" == "--set-alarm" ]]; then
    if [[ -z "$2" ]]; then
        alarmpath="$(yad --on-top --center --title="Select alarm sample path" --file)"
    else
        alarmpath="$(readlink -f -- "$2")" # must be absolute path
    fi
    [[ -f "$alarmpath" ]] || { superecho "No valid alarm path given." ; beep "2"; exit 1; }
    # f=force
    ln -fs "$alarmpath" "$config/alarm"
    exit
fi
# --set-remind (via softlink)
if [[ "$1" == "--set-remind" ]]; then
    if [[ -z "$2" ]]; then
        remindpath="$(yad --on-top --center --title="Select reminder sample path" --file)"
    else
        remindpath="$(readlink -f -- "$2")" # must be absolute path
    fi
    [[ -f "$remindpath" ]] || { superecho "No valid reminder path given." ; beep "2"; exit 1; }
    # f=force
    ln -fs "$remindpath" "$config/remind"
    exit
fi

# main
if [[ "$1" != "--reaction" ]] ; then
    if [[ "$1" == "--nr" ]] ; then       # --nr must be first
        # chop off first argument
        noreason="true" && shift
    fi
    if [[ "${!#}" == "--alarm" ]] ; then # --alarm must be last
        # chop off last argument
        alarm="--alarm" && set -- "${@:1:$(($#-1))}"
        testAlarmPath
    fi
    # input
    attime="$*" #concat
    # special case for minutes
    if [[ $attime == ?(-)+([0-9]) ]] ; then # is integer
        attime="now + $attime minutes"
        # lets add delay in seconds, since 'at' is only about minutes,
        # making this shortcut the only to seconds precise format.
        setdelay="1"
    fi
    
    # validate at time format, exit if fails
    validate "$attime" || { >&2 superecho "at time format error." ; beep "2"; exit 1; } # beep two times for error
    
    # user input reason
    if [[ $noreason != true ]]; then
        read -rp "reason? " reason || reason="$(yad --on-top --center --title="beepmein" --width=300 --separator="" --form --field="reason?")"
    fi
    [[ -z "$reason" ]] && reason="beep beep beep"
    echo "beepmein: $attime, reason: $reason $alarm"
    
    # if custom input
    (( setdelay )) && delay="$(date +%_S.%N)"
    
    # set 'at'
    at "$attime" <<< "$(echo "sleep $delay; DISPLAY=${DISPLAY} beepmein --reaction $alarm '${reason}'")" &>/dev/null || { superecho "at input error." ; beep "2"; exit 1; } # beep two times for error
    
else
    # reaction
    shift
    if [ "$1" == "--alarm" ]; then
        shift
        notify-send "$1" &
        blink 3 0.2 &>/dev/null &
        playa "$alarmSample" || alarmfailsafe
        wait
    else
        notify-send "$1" &
        blink 1 0 &>/dev/null &
        playa "$reminderSample" || beep "3"
        wait
    fi
fi