#!/bin/bash
#
# Crumbforest Native Installation Script
# Installs Crumbforest directly on Linux server without Docker
#
# Requirements:
# - Debian/Ubuntu Linux
# - Python 3.11+
# - MariaDB/MySQL
# - NGINX
# - Qdrant running on localhost:6333
#
# Run as root or with sudo
#

set -e  # Exit on error

# Colors
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
RED='\033[0;31m'
BLUE='\033[0;34m'
NC='\033[0m' # No Color

# Configuration
INSTALL_DIR="/opt/crumbforest"
APP_USER="crumbforest"
APP_GROUP="crumbforest"
LOG_DIR="/var/log/crumbforest"
SYSTEMD_DIR="/etc/systemd/system"
NGINX_SITES="/etc/nginx/sites-available"
NGINX_ENABLED="/etc/nginx/sites-enabled"
SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
PROJECT_ROOT="$(dirname "$SCRIPT_DIR")"

# Functions
print_success() {
    echo -e "${GREEN}✓${NC} $1"
}

print_warning() {
    echo -e "${YELLOW}⚠${NC} $1"
}

print_error() {
    echo -e "${RED}✗${NC} $1"
}

print_info() {
    echo -e "${BLUE}ℹ${NC} $1"
}

check_root() {
    if [ "$EUID" -ne 0 ]; then
        print_error "Bitte als root ausführen oder sudo verwenden"
        exit 1
    fi
}

check_command() {
    if command -v $1 &> /dev/null; then
        print_success "$1 ist installiert"
        return 0
    else
        print_error "$1 ist NICHT installiert"
        return 1
    fi
}

# Banner
echo "============================================"
echo "🦉 Crumbforest Native Installation"
echo "============================================"
echo ""
print_info "Installation nach: $INSTALL_DIR"
print_info "App User: $APP_USER"
print_info "Logs: $LOG_DIR"
echo ""

# Step 1: Check prerequisites
echo "=== Step 1: Prerequisites Check ==="
echo ""

check_root

all_ok=true

if ! check_command python3; then
    print_error "Python 3 ist erforderlich!"
    all_ok=false
else
    PYTHON_VERSION=$(python3 --version | awk '{print $2}')
    print_info "Python Version: $PYTHON_VERSION"
fi

if ! check_command pip3; then
    print_error "pip3 ist erforderlich!"
    all_ok=false
fi

if ! check_command nginx; then
    print_error "NGINX ist erforderlich!"
    all_ok=false
fi

if ! check_command mysql || ! check_command mariadb; then
    print_warning "MySQL/MariaDB CLI nicht gefunden (Server könnte trotzdem laufen)"
fi

# Check if Qdrant is running
if curl -s http://localhost:6333/collections > /dev/null 2>&1; then
    print_success "Qdrant läuft auf localhost:6333"
else
    print_warning "Qdrant nicht erreichbar auf localhost:6333 (wird später benötigt)"
fi

if [ "$all_ok" = false ]; then
    print_error "Bitte installiere die fehlenden Dependencies"
    exit 1
fi

echo ""

# Step 2: Create system user
echo "=== Step 2: System User Setup ==="
echo ""

if id "$APP_USER" &>/dev/null; then
    print_warning "User $APP_USER existiert bereits"
else
    useradd --system --no-create-home --shell /bin/false "$APP_USER"
    print_success "User $APP_USER erstellt"
fi

echo ""

# Step 3: Create directory structure
echo "=== Step 3: Directory Structure ==="
echo ""

print_info "Erstelle Verzeichnisse..."
mkdir -p "$INSTALL_DIR"/{app,docs,logs,venv}
mkdir -p "$LOG_DIR"

print_success "Verzeichnisse erstellt"

# Step 4: Copy application files
echo ""
echo "=== Step 4: Copy Application Files ==="
echo ""

print_info "Kopiere Application Code..."
cp -r "$PROJECT_ROOT/app"/* "$INSTALL_DIR/app/"
print_success "App Code kopiert"

print_info "Kopiere Dokumentation..."
# Check for docs_git (preferred source) or docs
DOCS_SOURCE=""
if [ -d "$PROJECT_ROOT/docs_git" ]; then
    DOCS_SOURCE="$PROJECT_ROOT/docs_git"
    print_info "Nutze docs_git als Quelle"
elif [ -d "$PROJECT_ROOT/docs" ]; then
    DOCS_SOURCE="$PROJECT_ROOT/docs"
    print_info "Nutze docs als Quelle"
fi

if [ -n "$DOCS_SOURCE" ]; then
    cp -r "$DOCS_SOURCE"/* "$INSTALL_DIR/docs/" || true
    
    # Fix: Create symlink in app/docs so hardcoded paths work (mimics Docker volume)
    if [ ! -L "$INSTALL_DIR/app/docs" ]; then
        # Remove empty dir if it exists
        if [ -d "$INSTALL_DIR/app/docs" ]; then rmdir "$INSTALL_DIR/app/docs" 2>/dev/null || true; fi
        ln -sf "$INSTALL_DIR/docs" "$INSTALL_DIR/app/docs"
        print_success "Docs Symlink erstellt (app/docs -> ../docs)"
    fi
    print_success "Docs kopiert von $(basename "$DOCS_SOURCE")"
else
    print_warning "Kein Dokumentations-Verzeichnis (docs_git oder docs) gefunden"
fi

print_info "Kopiere Root Dokumentation..."
cp "$PROJECT_ROOT"/*.md "$INSTALL_DIR/docs/" 2>/dev/null || true

print_info "Kopiere Konfiguration..."
if [ -f "$PROJECT_ROOT/crumbforest_config.json" ]; then
    cp "$PROJECT_ROOT/crumbforest_config.json" "$INSTALL_DIR/app/"
    print_success "Config kopiert"
fi

echo ""

# Step 5: Python virtual environment
echo "=== Step 5: Python Virtual Environment ==="
echo ""

print_info "Erstelle Virtual Environment..."
python3 -m venv "$INSTALL_DIR/venv"
print_success "venv erstellt"

print_info "Installiere Python Dependencies..."
"$INSTALL_DIR/venv/bin/pip" install --upgrade pip
"$INSTALL_DIR/venv/bin/pip" install -r "$PROJECT_ROOT/app/requirements.txt"
print_success "Dependencies installiert"

echo ""

# Step 6: Environment configuration
echo "=== Step 6: Environment Configuration ==="
echo ""

if [ ! -f "$INSTALL_DIR/.env" ]; then
    print_info "Erstelle .env aus Template..."
    cp "$SCRIPT_DIR/env.production.template" "$INSTALL_DIR/.env"
    
    # Generate random secrets
    APP_SECRET=$(openssl rand -hex 32)
    SECRET_KEY=$(openssl rand -hex 32)
    DB_PASSWORD=$(openssl rand -base64 24 | tr -d "=+/" | cut -c1-20)
    
    # Replace placeholders
    sed -i "s/CHANGE_ME_TO_RANDOM_64_CHAR_STRING/$APP_SECRET/g" "$INSTALL_DIR/.env"
    sed -i "s/CHANGE_ME_TO_SECURE_PASSWORD/$DB_PASSWORD/g" "$INSTALL_DIR/.env"
    
    print_success ".env erstellt"
    print_warning "WICHTIG: Bitte API Keys in $INSTALL_DIR/.env eintragen!"
else
    print_warning ".env existiert bereits - wird nicht überschrieben"
fi

echo ""

# Step 7: Set permissions
echo "=== Step 7: Permissions ==="
echo ""

print_info "Setze Besitzer und Rechte..."
chown -R "$APP_USER:$APP_GROUP" "$INSTALL_DIR"
chown -R "$APP_USER:$APP_GROUP" "$LOG_DIR"

chmod 750 "$INSTALL_DIR"
chmod 750 "$INSTALL_DIR/app"
chmod 600 "$INSTALL_DIR/.env"  # Sensitive data!
chmod -R 755 "$INSTALL_DIR/app/static" 2>/dev/null || true

# Fix: Symlink .env to app directory for Pydantic Settings
if [ ! -L "$INSTALL_DIR/app/.env" ]; then
    print_info "Erstelle Symlink für .env in App-Verzeichnis..."
    ln -sf "$INSTALL_DIR/.env" "$INSTALL_DIR/app/.env"
fi
chown -h $APP_USER:$APP_GROUP "$INSTALL_DIR/app/.env"

print_success "Permissions gesetzt"

echo ""

# Step 8: Install systemd services
echo "=== Step 8: systemd Services ==="
echo ""

print_info "Installiere systemd Service Files..."
cp "$SCRIPT_DIR/systemd/crumbforest.service" "$SYSTEMD_DIR/"
cp "$SCRIPT_DIR/systemd/crumbforest-indexing.service" "$SYSTEMD_DIR/"
print_success "Service Files kopiert"

print_info "Aktiviere Services..."
systemctl daemon-reload
systemctl enable crumbforest.service
systemctl enable crumbforest-indexing.service
print_success "Services aktiviert"

echo ""

# Step 9: Install NGINX configuration
echo "=== Step 9: NGINX Configuration ==="
echo ""

print_info "Installiere NGINX Config..."
cp "$SCRIPT_DIR/nginx/crumbforest.nginx.conf" "$NGINX_SITES/crumbforest"
cp "$SCRIPT_DIR/nginx/crumbforest-locations.conf" "$NGINX_SITES/"
print_success "NGINX Config installiert"

# Enable site
if [ ! -L "$NGINX_ENABLED/crumbforest" ]; then
    ln -s "$NGINX_SITES/crumbforest" "$NGINX_ENABLED/crumbforest"
    print_success "NGINX Site aktiviert"
else
    print_warning "NGINX Site bereits aktiviert"
fi

# Test NGINX config
if nginx -t > /dev/null 2>&1; then
    print_success "NGINX Config Test OK"
else
    print_error "NGINX Config Test FAILED - bitte prüfen!"
fi

echo ""

# Step 10: Install Crumb Doktor (Global Tool)
echo "=== Step 10: Install Crumb Doktor ==="
echo ""

DOKTOR_SRC="$PROJECT_ROOT/crumbpages-doktor.sh"
DOKTOR_DEST="/usr/local/bin/crumb-doktor"

if [ -f "$DOKTOR_SRC" ]; then
    print_info "Installiere crumbpages-doktor.sh als globalen Befehl..."
    cp "$DOKTOR_SRC" "$DOKTOR_DEST"
    chmod +x "$DOKTOR_DEST"
    print_success "Installiert als: $DOKTOR_DEST"
    print_info "Du kannst jetzt überall 'crumb-doktor' verwenden!"
else
    print_warning "crumbpages-doktor.sh nicht gefunden im Repo-Root"
fi

echo ""

# Step 11: Database setup reminder
echo "=== Step 11: Database Setup ==="
echo ""
print_warning "Datenbank muss manuell eingerichtet werden!"
echo ""
echo "Bitte folgende SQL-Befehle ausführen:"
echo ""
echo "  mysql -u root -p"
echo "  CREATE DATABASE IF NOT EXISTS crumbforest CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;"
echo "  CREATE USER IF NOT EXISTS 'crumb_prod'@'localhost' IDENTIFIED BY 'YOUR_PASSWORD';"
echo "  GRANT ALL PRIVILEGES ON crumbforest.* TO 'crumb_prod'@'localhost';"
echo "  FLUSH PRIVILEGES;"
echo ""
echo "Dann Datenbank-Schema importieren:"
echo "  mysql -u crumb_prod -p crumbforest < $PROJECT_ROOT/compose/init/01_schema.sql"
echo ""

read -p "Drücke ENTER wenn Datenbank eingerichtet ist..."

echo ""

# Summary
echo "============================================"
echo "✓ Installation abgeschlossen!"
echo "============================================"
echo ""
echo "Nächste Schritte:"
echo ""
echo "1. API Keys eintragen:"
echo "   sudo nano $INSTALL_DIR/.env"
echo ""
echo "2. Services starten:"
echo "   sudo systemctl start crumbforest-indexing  # Einmalig"
echo "   sudo systemctl start crumbforest"
echo ""
echo "3. NGINX neu laden:"
echo "   sudo systemctl reload nginx"
echo ""
echo "4. Status prüfen:"
echo "   sudo systemctl status crumbforest"
echo "   sudo journalctl -u crumbforest -f"
echo ""
echo "5. Health Check:"
echo "   curl http://localhost:8000/health"
echo ""
echo "URLs:"
echo "  - App: http://crumbforest.194-164-194-191.sslip.io"
echo "  - IP:  http://194.164.194.191"
echo ""
echo "Installation Location: $INSTALL_DIR"
echo "Logs: $LOG_DIR"
echo "systemd Logs: journalctl -u crumbforest"
echo ""
echo "Wuuuuhuuu! 🦉💚"
echo ""