#!/bin/bash
# notify - show a macOS notification via osascript
#
# Usage:
#   notify [options] [message ...]
#   command | notify [options]
#   notify -h
#
# Options:
#   -t, --title TITLE        Notification title (default: "Notification")
#   -s, --subtitle SUBTITLE  Notification subtitle
#       --sound SOUND        Sound name (default: "Glass")
#   -n, --no-sound           Suppress notification sound
#   -l, --list-sounds        List available sound names and exit
#   -h, --help               Show help and exit
#
# Environment:
#   NOTIFY_TITLE  Default title (overridden by --title)
#   NOTIFY_SOUND  Default sound (overridden by --sound / --no-sound)
#
# macOS only. osascript is the backing mechanism for notifications

_notify() (
    local SCRIPT_NAME; SCRIPT_NAME="$(basename "${BASH_SOURCE[0]}")"
    case "${BASH_SOURCE[0]}" in /dev/*|/proc/*) SCRIPT_NAME="" ;; esac
    case "$SCRIPT_NAME" in ""|bash|sh|zsh|dash) SCRIPT_NAME="notify" ;; esac

    _color() { [ -t 2 ] && [ -z "${NO_COLOR:-}" ] && printf '%s' "$1"; }
    _error() { printf '%s[ERR][%s] %s%s\n' "$(_color $'\033[31m')" "$SCRIPT_NAME" "$*" "$(_color $'\033[0m')" >&2; }

    _show_help() {
        local s; [ -t 1 ] && s=$'\033[4m'
        local r; [ -t 1 ] && r=$'\033[24m'
        echo "NAME"
        echo "  $SCRIPT_NAME - show a macOS notification via osascript"
        echo "SYNOPSIS"
        echo "  $SCRIPT_NAME [${s}options${r}] [${s}message${r} ...]"
        echo "  ${s}command${r} | $SCRIPT_NAME [${s}options${r}]"
        echo "  $SCRIPT_NAME -h"
        echo "DESCRIPTION"
        echo "  Displays a macOS notification in the top-right corner and in"
        echo "  Notification Center. The ${s}message${r} may be passed as positional"
        echo "  arguments or piped to stdin."
        echo ""
        echo "  Notifications are attributed to Script Editor (the osascript host"
        echo "  app). Notification duration is controlled by macOS, not this script"
        echo "  (System Settings > Notifications > Script Editor)."
        echo "OPTIONS"
        echo "  -t, --title ${s}title${r}        Notification title (default: \"Notification\")"
        echo "  -s, --subtitle ${s}subtitle${r}  Notification subtitle"
        echo "      --sound ${s}sound${r}        Sound name (default: \"Glass\")"
        echo "  -n, --no-sound           Suppress notification sound"
        echo "  -l, --list-sounds        List available sound names and exit"
        echo "  -h, --help               Show this help message"
        echo "ENVIRONMENT"
        echo "  NOTIFY_TITLE    Default title (overridden by --title)"
        echo "  NOTIFY_SOUND    Default sound (overridden by --sound / --no-sound)"
        echo "EXIT STATUS"
        echo "  0  Success"
        echo "  2  Invalid arguments or missing required message"
        echo "  3  osascript not found (not running on macOS)"
        echo "DEPENDENCIES"
        echo "  osascript (macOS)"
        echo "CAVEATS"
        echo "  macOS only. osascript is the backing mechanism for notifications."
    }

    _list_sounds() {
        local sounds=""
        local dir
        local file
        local name

        for dir in /System/Library/Sounds ~/Library/Sounds; do
            [ -d "$dir" ] || continue
            for file in "$dir"/*; do
                [ -f "$file" ] || continue
                name="${file##*/}"
                name="${name%.*}"
                sounds="${sounds:+$sounds$'\n'}$name"
            done
        done

        if [ -z "$sounds" ]; then
            _error "No sounds found in /System/Library/Sounds/ or ~/Library/Sounds/"
            return 1
        fi

        printf '%s\n' "$sounds" | sort
    }

    _expand_short_opts() {
        # $1 = string of short-opt letters that take a value (e.g. "nXHd"); "" for flag-only scripts
        # $2..$N = "$@"
        # Populates _EXPANDED; caller does: set -- "${_EXPANDED[@]}"; unset _EXPANDED
        local value_opts="$1"; shift
        _EXPANDED=()
        local passthru=""
        local arg
        local rest
        local c
        for arg in "$@"; do
            if [ -n "$passthru" ]; then _EXPANDED+=("$arg"); continue; fi
            case "$arg" in
                --)          passthru=1; _EXPANDED+=("$arg") ;;
                --*|-|"")    _EXPANDED+=("$arg") ;;
                -[a-zA-Z]?*)
                    rest="${arg#-}"
                    while [ -n "$rest" ]; do
                        c="${rest%"${rest#?}"}"; rest="${rest#?}"
                        _EXPANDED+=("-$c")
                        case "$value_opts" in *"$c"*)
                            [ -n "$rest" ] && _EXPANDED+=("$rest")
                            rest="" ;;
                        esac
                    done ;;
                *)           _EXPANDED+=("$arg") ;;
            esac
        done
    }
    if ! command -v osascript >/dev/null 2>&1; then
        _error "osascript not found (macOS only)"
        return 3
    fi

    local title="${NOTIFY_TITLE:-Notification}"
    local subtitle=""
    local sound="${NOTIFY_SOUND:-Glass}"
    local no_sound=""
    local list_sounds=""
    local -a args=()

    _expand_short_opts "ts" "$@"
    set -- "${_EXPANDED[@]}"; unset _EXPANDED

    while [ $# -gt 0 ]; do
        case "$1" in
            -h|--help)
                _show_help
                return 0
                ;;
            -l|--list-sounds)
                list_sounds=1
                shift
                ;;
            -n|--no-sound)
                no_sound=1
                shift
                ;;
            -t|--title)
                [ -n "${2-}" ] || { _error "-t|--title requires a value. Run \`$SCRIPT_NAME -h\` for usage"; return 2; }
                title="$2"
                shift 2
                ;;
            --title=*)
                title="${1#*=}"
                [ -n "$title" ] || { _error "-t|--title requires a value. Run \`$SCRIPT_NAME -h\` for usage"; return 2; }
                shift
                ;;
            -s|--subtitle)
                [ -n "${2-}" ] || { _error "-s|--subtitle requires a value. Run \`$SCRIPT_NAME -h\` for usage"; return 2; }
                subtitle="$2"
                shift 2
                ;;
            --subtitle=*)
                subtitle="${1#*=}"
                [ -n "$subtitle" ] || { _error "-s|--subtitle requires a value. Run \`$SCRIPT_NAME -h\` for usage"; return 2; }
                shift
                ;;
            --sound)
                [ -n "${2-}" ] || { _error "--sound requires a value. Run \`$SCRIPT_NAME -h\` for usage"; return 2; }
                sound="$2"
                shift 2
                ;;
            --sound=*)
                sound="${1#*=}"
                [ -n "$sound" ] || { _error "--sound requires a value. Run \`$SCRIPT_NAME -h\` for usage"; return 2; }
                shift
                ;;
            --)
                shift
                while [ $# -gt 0 ]; do
                    args+=("$1")
                    shift
                done
                ;;
            -*)
                _error "Unknown argument '$1'. Run \`$SCRIPT_NAME -h\` for usage"
                return 2
                ;;
            *)
                args+=("$1")
                shift
                ;;
        esac
    done

    if [ -n "$list_sounds" ]; then
        _list_sounds
        return $?
    fi

    # Build message from positional args or stdin
    local message=""
    if [ ${#args[@]} -gt 0 ]; then
        message="${args[*]}"
    elif [ ! -t 0 ]; then
        message="$(cat)"
    fi

    if [ -z "$message" ]; then
        _error "MESSAGE is required (pass as argument or pipe to stdin)"
        _show_help >&2
        return 2
    fi

    local effective_sound="$sound"
    if [ -n "$no_sound" ]; then
        effective_sound=""
    fi

    osascript - "$message" "$title" "$subtitle" "$effective_sound" <<'APPLESCRIPT'
on run argv
    set msg to item 1 of argv
    set ttl to item 2 of argv
    set sub to item 3 of argv
    set snd to item 4 of argv
    if sub is "" and snd is "" then
        display notification msg with title ttl
    else if sub is "" then
        display notification msg with title ttl sound name snd
    else if snd is "" then
        display notification msg with title ttl subtitle sub
    else
        display notification msg with title ttl subtitle sub sound name snd
    end if
end run
APPLESCRIPT
)

_notify "$@"
__notify_rc=$?
unset -f _notify
if [ -n "${BASH_SOURCE[0]}" ] && [ "${BASH_SOURCE[0]}" != "$0" ]; then
    eval "unset __notify_rc; return $__notify_rc"
fi
eval "unset __notify_rc; exit $__notify_rc"