#!/bin/sh

usage() {
    printf "Usage: %s [-l DEBUG_LEVEL] [-v] [-h] [-t TIMEOUT] [-c COMMAND]\n\n" "$0"
}

help() {
    cat << EOH
 SYNOPSIS
    $0 [-l DEBUG_LEVEL] [-v] [-h] [-t TIMEOUT] [-c COMMAND]

 DESCRIPTION

    \`Timeout\` executes a command until the timeout is over.
    When the command is finished before the timeout then the exit code is \`0\` else it's \`1\`.

 OPTIONS

    -h    Show this help

    -l debug|info|notice|warning|error
          Debug level

    -v    Display  the command output (stderr)

    -c COMMAND
          The command to execute
          \`COMMAND=... $0\` works to.

    -t TIMEOUT
          The timeout in seconds (default: 10)
          \`TIMEOUT=... $0\` works to.
EOH
}

on_interrupt() {
    log -l notice "Process aborted!"

    exit 130
}

create_script() {
    printf "#!/bin/sh\n%s\n" "$1" > "$2"
    chmod +x "$SCRIPT_FILE"

    log -t -l debug "$SCRIPT_FILE created"
}

run_script() {
    if [ "$2" -eq 0 ]; then
        "$SCRIPT_FILE" >/dev/null 2>&1 &
    else
        "$SCRIPT_FILE" 2>"$LOG_FILE" >&2 &
    fi

    log -t -l debug "$SCRIPT_FILE started"

    printf "%d" $!
}

stop_delete_script() {
    (
        kill -9 "$1" 2>/dev/null \
        && log -t -l debug "Process \"$1\" killed"
    ) || log -t -l debug "Process \"$1\" does not exist"

    test -f "$2" && rm -f "$2"
    test -f "$3" && rm -f "$3"
}

check_pid() {
    PID=$1
    LOOP=$2

    for _ in $(seq 1 "$((LOOP*2))"); do
        test -d "/proc/$PID/" && sleep 0.5 || STATUS=0
    done

    printf "%d" ${STATUS:-1}
}

main() {
    while getopts "l:ht:c:v" option; do
        case "${option}" in
            h) help; exit 0;;
            t) TIMEOUT="$OPTARG";;
            c) COMMAND="$OPTARG";;
            l) LOG_VERBOSE="$OPTARG";;
            v) VERBOSE=1;;
            ?) log -l error "$(usage)"; exit 1;;
        esac
    done

    TIMEOUT="${TIMEOUT:-10}"
    VERBOSE="${VERBOSE:-0}"

    if [ -z "$COMMAND" ]; then
        log -l error "Command is required!"
        exit 1
    fi

    SCRIPT_FILE="$(mktemp)"
    LOG_FILE="$(mktemp)"

    create_script "$COMMAND" "$SCRIPT_FILE"

    SCRIPT_PID=$(run_script "$SCRIPT_FILE" "$VERBOSE")

    (
        test -f "$LOG_FILE" && tail -f "$LOG_FILE" | while read -r OUTPUT; do
            LOG_VERBOSE=info log -t -l info "$OUTPUT"
        done
    )&

    EXIT_STATUS=$(check_pid "$SCRIPT_PID" "$TIMEOUT")

    stop_delete_script "$SCRIPT_PID" "$SCRIPT_FILE" "$LOG_FILE"

    log -t -l debug "Exit code is $EXIT_STATUS"

    exit "$EXIT_STATUS"
}

log() {
    LOG_VERBOSE="${LOG_VERBOSE:-info}"
    LEVEL=info
    TIME=

    while getopts "tl:" option; do
        case "${option}" in
            l) LEVEL="$OPTARG"; shift $((OPTIND-1));;
            t) TIME="$(printf "[%s] " "$(date +'%Y-%m-%dT%H:%M:%S.%s')")"; shift $((OPTIND-1));;
            *) exit 1;;
        esac
    done

    if [ -t 2 ] && [ -z "${NO_COLOR-}" ]; then
        case "${LEVEL}" in
            debug) COLOR="$(tput setaf 3)";;
            notice) COLOR="$(tput setaf 4)";;
            warning) COLOR="$(tput setaf 5)";;
            error) COLOR="$(tput setaf 1)";;
            *) COLOR="$(tput sgr0)";;
        esac
    fi

    case "${LEVEL}" in
        debug) LEVEL=100;;
        notice) LEVEL=250;;
        warning) LEVEL=300;;
        error) LEVEL=400;;
        *) LEVEL=200;;
    esac

    case "${LOG_VERBOSE}" in
        debug) LOG_VERBOSE_VALUE=100;;
        notice) LOG_VERBOSE_VALUE=250;;
        warning) LOG_VERBOSE_VALUE=300;;
        error) LOG_VERBOSE_VALUE=400;;
        *) LOG_VERBOSE_VALUE=200;;
    esac

    if [ $LEVEL -ge $LOG_VERBOSE_VALUE ]; then
        printf "%s\n" "$*" | while IFS='' read -r LINE; do
            printf "%s%s%s\n" "${COLOR:-}" "${TIME:-}" "$LINE" >&2
        done
    fi
}

trap on_interrupt INT

main "$@"