#!/usr/bin/env bash
# ══════════════════════════════════════════════════════════════
#  Image Folder Watcher – plattformübergreifende Installation
#  Unterstützt: macOS (launchd) und Linux (systemd)
#  Nutzt ein Python-venv – kein --break-system-packages nötig.
# ══════════════════════════════════════════════════════════════

set -euo pipefail

GREEN='\033[0;32m'; YELLOW='\033[1;33m'; RED='\033[0;31m'; NC='\033[0m'
info()  { echo -e "${YELLOW}$*${NC}"; }
ok()    { echo -e "${GREEN}$*${NC}"; }
err()   { echo -e "${RED}$*${NC}" >&2; }

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
OS="$(uname -s)"

echo -e "${GREEN}══════════════════════════════════════════════════${NC}"
echo -e "${GREEN}  Image Folder Watcher – Installation (${OS})${NC}"
echo -e "${GREEN}══════════════════════════════════════════════════${NC}"

INSTALL_DIR="${INSTALL_DIR:-$HOME/image-folder-watcher}"
VENV_DIR="$INSTALL_DIR/.venv"

# Sinnvolle Standard-Überwachungsordner je Plattform (per ENV überschreibbar)
if [[ "$OS" == "Darwin" ]]; then
    WATCH_DIR="${WATCH_DIR:-$HOME/Pictures/Eingang}"
else
    WATCH_DIR="${WATCH_DIR:-$HOME/Bilder/Eingang}"
fi

# ── 1. Python sicherstellen + System-Pakete ──────────────────────────────────
info "\n[1/4] Prüfe Python & installiere ggf. System-Voraussetzungen..."

ensure_python_linux() {
    if command -v pacman &>/dev/null; then
        sudo pacman -S --needed --noconfirm python
    elif command -v apt-get &>/dev/null; then
        sudo apt-get update -qq
        sudo apt-get install -y python3 python3-venv python3-pip
    elif command -v dnf &>/dev/null; then
        sudo dnf install -y python3 python3-pip
    elif command -v zypper &>/dev/null; then
        sudo zypper install -y python3 python3-pip
    else
        err "  Kein bekannter Paketmanager (pacman/apt/dnf/zypper) gefunden."
        err "  Bitte Python 3 + venv manuell installieren und Script erneut starten."
        exit 1
    fi
}

ensure_python_macos() {
    if ! command -v python3 &>/dev/null; then
        if command -v brew &>/dev/null; then
            brew install python
        else
            err "  Python 3 nicht gefunden und Homebrew ist nicht installiert."
            err "  Installiere Python von https://www.python.org/downloads/ ODER"
            err "  Homebrew von https://brew.sh und starte dann erneut."
            exit 1
        fi
    fi
    # Xcode Command Line Tools liefern viele Build-Voraussetzungen; pillow-heif
    # nutzt aber vorgebaute Wheels, daher i.d.R. nicht zwingend nötig.
}

case "$OS" in
    Darwin) ensure_python_macos ;;
    Linux)  ensure_python_linux ;;
    *)      err "  Nicht unterstütztes OS: $OS"; exit 1 ;;
esac

PYTHON="$(command -v python3)"
ok "  ✅ Python: $PYTHON ($($PYTHON --version))"

# ── 2. venv anlegen & Abhängigkeiten installieren ────────────────────────────
info "\n[2/4] Erstelle virtuelle Umgebung & installiere Abhängigkeiten..."
mkdir -p "$INSTALL_DIR"
if [[ ! -d "$VENV_DIR" ]]; then
    "$PYTHON" -m venv "$VENV_DIR"
fi
"$VENV_DIR/bin/pip" install --upgrade pip --quiet
"$VENV_DIR/bin/pip" install -r "$SCRIPT_DIR/requirements.txt"
ok "  ✅ Pillow, watchdog, pillow-heif (HEIC/HEIF) installiert."

# ── 3. Script + Überwachungsordner ───────────────────────────────────────────
info "\n[3/4] Kopiere Script nach $INSTALL_DIR & erstelle Ordner..."
cp "$SCRIPT_DIR/watcher.py" "$INSTALL_DIR/watcher.py"
chmod +x "$INSTALL_DIR/watcher.py"
mkdir -p "$WATCH_DIR"
ok "  ✅ Überwachungsordner: $WATCH_DIR"

VENV_PYTHON="$VENV_DIR/bin/python"

# ── 4. Autostart (optional, plattformabhängig) ───────────────────────────────
info "\n[4/4] Autostart einrichten?"
read -rp "Autostart-Dienst installieren? [j/N] " INSTALL_SERVICE
if [[ "$INSTALL_SERVICE" =~ ^[jJyY]$ ]]; then
    if [[ "$OS" == "Darwin" ]]; then
        # ── macOS: launchd User-Agent ──
        LABEL="work.datenhimmel.image-watcher"
        PLIST_DIR="$HOME/Library/LaunchAgents"
        PLIST="$PLIST_DIR/$LABEL.plist"
        mkdir -p "$PLIST_DIR"
        sed -e "s|__LABEL__|$LABEL|g" \
            -e "s|__PYTHON__|$VENV_PYTHON|g" \
            -e "s|__SCRIPT__|$INSTALL_DIR/watcher.py|g" \
            -e "s|__WATCH_DIR__|$WATCH_DIR|g" \
            -e "s|__WORKDIR__|$INSTALL_DIR|g" \
            "$SCRIPT_DIR/launchd/image-watcher.plist.template" > "$PLIST"
        # Neu laden (bootout ignoriert Fehler falls noch nicht geladen)
        launchctl bootout "gui/$(id -u)/$LABEL" 2>/dev/null || true
        launchctl bootstrap "gui/$(id -u)" "$PLIST"
        ok "  ✅ launchd-Agent installiert & gestartet!"
        echo "     Status:   launchctl print gui/$(id -u)/$LABEL | head"
        echo "     Stoppen:  launchctl bootout gui/$(id -u)/$LABEL"
        echo "     Logs:     tail -f $INSTALL_DIR/watcher.out.log"
    else
        # ── Linux: systemd System-Service ──
        SERVICE_NAME="image-watcher.service"
        TMP_SERVICE="$INSTALL_DIR/$SERVICE_NAME"
        sed -e "s|__PYTHON__|$VENV_PYTHON|g" \
            -e "s|__SCRIPT__|$INSTALL_DIR/watcher.py|g" \
            -e "s|__WATCH_DIR__|$WATCH_DIR|g" \
            -e "s|__WORKDIR__|$INSTALL_DIR|g" \
            -e "s|__USER__|$USER|g" \
            "$SCRIPT_DIR/systemd/image-watcher.service.template" > "$TMP_SERVICE"
        sudo cp "$TMP_SERVICE" "/etc/systemd/system/$SERVICE_NAME"
        sudo systemctl daemon-reload
        sudo systemctl enable "$SERVICE_NAME"
        sudo systemctl restart "$SERVICE_NAME"
        ok "  ✅ systemd-Service installiert & gestartet!"
        echo "     Status: sudo systemctl status image-watcher"
        echo "     Logs:   journalctl -u image-watcher -f"
    fi
fi

echo -e "\n${GREEN}══════════════════════════════════════════════════${NC}"
ok "  ✅ Installation abgeschlossen!"
echo -e "${GREEN}══════════════════════════════════════════════════${NC}"
echo ""
echo "  Manuell starten:"
echo "    $VENV_PYTHON $INSTALL_DIR/watcher.py \"$WATCH_DIR\""
echo ""
echo "  Mit Optionen:"
echo "    $VENV_PYTHON $INSTALL_DIR/watcher.py \"$WATCH_DIR\" --width 1920 --dpi 72 --format JPEG"
echo ""