#!/bin/bash

################################################################################
# VidRip Production Startup Script
################################################################################
# This script builds and runs the VidRip service in production mode.
# It handles dependency checks, builds both frontend and backend, and starts
# the backend server with proper process management.
################################################################################

set -e  # Exit on error
set -u  # Exit on undefined variable

# Parse command line arguments
USE_SYSTEMD=false
while [[ $# -gt 0 ]]; do
    case $1 in
        --systemd)
            USE_SYSTEMD=true
            shift
            ;;
        --help|-h)
            echo "Usage: $0 [OPTIONS]"
            echo ""
            echo "Options:"
            echo "  --systemd    Use systemd service instead of nohup (requires sudo)"
            echo "  --help       Show this help message"
            exit 0
            ;;
        *)
            echo "Unknown option: $1"
            echo "Use --help for usage information"
            exit 1
            ;;
    esac
done

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

# Script directory
WEB_ROOT="/var/www/vidrip"
SCRIPT_DIR=$(pwd)
echo -e "$SCRIPT_DIR"

rm -rf "$WEB_ROOT/*"
cd "$SCRIPT_DIR"

# Configuration
BACKEND_DIR="$SCRIPT_DIR/backend"
FRONTEND_DIR="$SCRIPT_DIR/frontend"
LOG_DIR="$SCRIPT_DIR/logs"
PID_FILE="$SCRIPT_DIR/vidrip.pid"
LOG_FILE="$LOG_DIR/vidrip.log"
ERROR_LOG_FILE="$LOG_DIR/vidrip-error.log"

################################################################################
# Helper Functions
################################################################################

log_info() {
    echo -e "${BLUE}[INFO]${NC} $1"
}

log_success() {
    echo -e "${GREEN}[SUCCESS]${NC} $1"
}

log_warning() {
    echo -e "${YELLOW}[WARNING]${NC} $1"
}

log_error() {
    echo -e "${RED}[ERROR]${NC} $1"
}

check_command() {
    if ! command -v "$1" &> /dev/null; then
        log_error "$1 is not installed or not in PATH"
        return 1
    fi
    log_success "$1 is installed"
    return 0
}

cleanup_on_exit() {
    log_info "Cleaning up..."
    if [ -f "$PID_FILE" ]; then
        rm -f "$PID_FILE"
    fi
}

################################################################################
# Pre-flight Checks
################################################################################

log_info "Starting VidRip production deployment..."
echo ""

log_info "Checking system requirements..."

# Check for Node.js
if ! check_command node; then
    log_error "Node.js is required but not installed"
    exit 1
fi

NODE_VERSION=$(node --version | cut -d'v' -f2 | cut -d'.' -f1)
if [ "$NODE_VERSION" -lt 18 ]; then
    log_error "Node.js version 18 or higher is required (found v$NODE_VERSION)"
    exit 1
fi
log_success "Node.js version: $(node --version)"

# Check for npm
if ! check_command npm; then
    log_error "npm is required but not installed"
    exit 1
fi

# Check for yt-dlp
if ! check_command yt-dlp; then
    log_warning "yt-dlp is not installed or not in PATH"
    log_warning "Install with: pip install yt-dlp OR brew install yt-dlp"
    log_warning "The application will not be able to download videos without yt-dlp"
else
    log_success "yt-dlp version: $(yt-dlp --version)"
fi

echo ""

################################################################################
# Check for existing process
################################################################################

if [ -f "$PID_FILE" ]; then
    OLD_PID=$(cat "$PID_FILE")
    if ps -p "$OLD_PID" > /dev/null 2>&1; then
        log_error "VidRip is already running (PID: $OLD_PID)"
        log_info "Stop it first with: kill $OLD_PID"
        exit 1
    else
        log_warning "Stale PID file found, removing..."
        rm -f "$PID_FILE"
    fi
fi

################################################################################
# Create necessary directories
################################################################################

log_info "Creating necessary directories..."
mkdir -p "$LOG_DIR"
mkdir -p "$BACKEND_DIR/downloads"
mkdir -p "$BACKEND_DIR/dist"
log_success "Directories created"

echo ""

################################################################################
# Install Dependencies
################################################################################

log_info "Installing dependencies..."

# Backend dependencies
log_info "Installing backend dependencies..."
cd "$BACKEND_DIR"
if [ ! -d "node_modules" ]; then
    npm install --production=false
else
    log_info "Backend node_modules already exists, skipping install"
fi
log_success "Backend dependencies installed"

# Frontend dependencies
log_info "Installing frontend dependencies..."
cd "$FRONTEND_DIR"
if [ ! -d "node_modules" ]; then
    npm install --production=false
else
    log_info "Frontend node_modules already exists, skipping install"
fi
log_success "Frontend dependencies installed"

cd "$SCRIPT_DIR"
echo ""

################################################################################
# Build Applications
################################################################################

log_info "Building applications..."

# Build backend
log_info "Building backend (TypeScript compilation)..."
cd "$BACKEND_DIR"
npm run build
if [ ! -f "dist/server.js" ]; then
    log_error "Backend build failed - dist/server.js not found"
    exit 1
fi
log_success "Backend built successfully"

# Build frontend
log_info "Building frontend (Vite production build)..."
cd "$FRONTEND_DIR"
npm run build
if [ ! -d "dist" ]; then
    log_error "Frontend build failed - dist directory not found"
    exit 1
fi
log_success "Frontend built successfully"

cd "$SCRIPT_DIR"
echo ""

################################################################################
# Generate Caddyfile (if needed)
################################################################################

if [ ! -f "$SCRIPT_DIR/Caddyfile" ]; then
    log_info "Caddyfile not found. Let's create one!"
    echo ""

    # Ask for domain
    read -p "Enter your domain name (or press Enter to skip): " DOMAIN_INPUT

    if [ -n "$DOMAIN_INPUT" ]; then
        log_info "Generating Caddyfile for domain: $DOMAIN_INPUT"

        cat > "$SCRIPT_DIR/Caddyfile" << EOF
# VidRip Caddyfile
# Auto-generated configuration for ${DOMAIN_INPUT}

${DOMAIN_INPUT} {
    # Enable compression
    encode gzip zstd

    # Security headers
    header {
        # Enable HSTS (forces HTTPS)
        Strict-Transport-Security "max-age=31536000; includeSubDomains; preload"
        # Prevent clickjacking
        X-Frame-Options "SAMEORIGIN"
        # Prevent MIME type sniffing
        X-Content-Type-Options "nosniff"
        # Enable XSS protection
        X-XSS-Protection "1; mode=block"
        # Referrer policy
        Referrer-Policy "strict-origin-when-cross-origin"
        # Remove server header for security
        -Server
    }

    # API routes - proxy to backend
    handle /api/* {
        reverse_proxy localhost:3001 {
            # Health check
            health_uri /api/health
            health_interval 10s
            health_timeout 5s

            # Headers
            header_up Host {host}
            header_up X-Real-IP {remote_host}
            header_up X-Forwarded-For {remote_host}
            header_up X-Forwarded-Proto {scheme}
        }
    }

    # Serve frontend static files
    handle {
        # Root directory is the frontend build output
        root * ${WEB_ROOT}

        # Try files first, fall back to index.html for SPA routing
        try_files {path} /index.html

        # Serve files
        file_server

        # Cache static assets
        @static {
            path *.js *.css *.woff *.woff2 *.ttf *.eot *.ico *.png *.jpg *.jpeg *.gif *.svg *.webp
        }
        header @static {
            Cache-Control "public, max-age=31536000, immutable"
        }

        # Don't cache index.html
        @html {
            path *.html
        }
        header @html {
            Cache-Control "no-cache, no-store, must-revalidate"
        }
    }

    # Logging
    log {
        output file /var/log/caddy/vidrip-access.log {
            roll_size 100mb
            roll_keep 10
        }
        format json
    }
}
EOF

        log_success "Caddyfile created successfully!"
        log_info "You can edit it later at: $SCRIPT_DIR/Caddyfile"
    else
        log_info "Skipping Caddyfile generation"
        log_info "You can create it manually later or use nginx/Apache"
    fi
    echo ""
else
    log_info "Caddyfile already exists, skipping generation"
    echo ""
fi

################################################################################
# Deploy Frontend to Web Root
################################################################################

log_info "Deploying frontend to web root..."

# Check if we have permissions to write to /var/www
if [ -w "/var/www" ]; then
    # Create web root directory
    sudo mkdir -p "$WEB_ROOT"

    # Copy frontend build to web root
    log_info "Copying frontend build to $WEB_ROOT..."
    sudo rm -rf "$WEB_ROOT"/*
    sudo cp -r "$FRONTEND_DIR/dist/"* "$WEB_ROOT/"

    # Set proper permissions
    sudo chown -R www-data:www-data "$WEB_ROOT" 2>/dev/null || sudo chown -R $USER:$USER "$WEB_ROOT"
    sudo chmod -R 755 "$WEB_ROOT"

    log_success "Frontend deployed to $WEB_ROOT"
else
    log_warning "No write permission to /var/www"
    log_warning "Run with sudo to deploy frontend, or manually copy:"
    log_warning "  sudo mkdir -p $WEB_ROOT"
    log_warning "  sudo cp -r $FRONTEND_DIR/dist/* $WEB_ROOT/"
    log_warning "  sudo chown -R www-data:www-data $WEB_ROOT"
    log_warning "  sudo chmod -R 755 $WEB_ROOT"
fi

echo ""

################################################################################
# Start Backend Server
################################################################################

log_info "Starting VidRip backend server..."

if [ "$USE_SYSTEMD" = true ]; then
    # Systemd mode
    log_info "Using systemd service..."

    # Check if running as root or with sudo
    if [ "$EUID" -ne 0 ]; then
        log_error "Systemd mode requires root privileges"
        log_error "Please run with: sudo $0 --systemd"
        exit 1
    fi

    # Check if service file exists
    SERVICE_FILE="$SCRIPT_DIR/vidrip-backend.service"
    if [ ! -f "$SERVICE_FILE" ]; then
        log_error "Service file not found: $SERVICE_FILE"
        log_error "Please ensure vidrip-backend.service exists in the project directory"
        exit 1
    fi

    # Update service file with correct paths
    TEMP_SERVICE="/tmp/vidrip-backend.service"
    sed -e "s|/opt/vidrip|$SCRIPT_DIR|g" \
        -e "s|User=vidrip|User=$SUDO_USER|g" \
        -e "s|Group=vidrip|Group=$SUDO_USER|g" \
        -e "s|/usr/bin/node|$(which node)|g" \
        "$SERVICE_FILE" > "$TEMP_SERVICE"

    # Install service file
    cp "$TEMP_SERVICE" /etc/systemd/system/vidrip-backend.service
    rm "$TEMP_SERVICE"

    log_info "Service file installed to /etc/systemd/system/vidrip-backend.service"

    # Reload systemd
    systemctl daemon-reload

    # Enable and start service
    systemctl enable vidrip-backend
    systemctl restart vidrip-backend

    # Wait and check status
    sleep 2
    if systemctl is-active --quiet vidrip-backend; then
        log_success "VidRip backend service started successfully!"
        echo ""
        systemctl status vidrip-backend --no-pager -l
    else
        log_error "Service failed to start"
        log_error "Check status with: sudo systemctl status vidrip-backend"
        log_error "View logs with: sudo journalctl -u vidrip-backend -n 50"
        exit 1
    fi

else
    # Traditional nohup mode
    log_info "Using nohup mode..."

    # Check for existing process
    if [ -f "$PID_FILE" ]; then
        OLD_PID=$(cat "$PID_FILE")
        if ps -p "$OLD_PID" > /dev/null 2>&1; then
            log_error "VidRip is already running (PID: $OLD_PID)"
            log_info "Stop it first with: ./stop-production.sh"
            exit 1
        else
            log_warning "Stale PID file found, removing..."
            rm -f "$PID_FILE"
        fi
    fi

    # Setup environment
    export NODE_ENV=production

    # Start the backend server
    cd "$BACKEND_DIR"

    # Run in background with output redirected to log files
    nohup node dist/server.js > "$LOG_FILE" 2> "$ERROR_LOG_FILE" &
    SERVER_PID=$!

    # Save PID
    echo "$SERVER_PID" > "$PID_FILE"

    # Wait a moment and check if process is still running
    sleep 2
    if ! ps -p "$SERVER_PID" > /dev/null 2>&1; then
        log_error "Server failed to start"
        log_error "Check logs at:"
        log_error "  - $LOG_FILE"
        log_error "  - $ERROR_LOG_FILE"
        rm -f "$PID_FILE"
        exit 1
    fi

    log_success "VidRip backend started successfully!"
    echo ""
    log_info "Process ID: $SERVER_PID"
    log_info "PID file: $PID_FILE"
    log_info "Log file: $LOG_FILE"
    log_info "Error log: $ERROR_LOG_FILE"
    echo ""

    # Check for port in logs (default 3001)
    sleep 1
    if grep -q "Server running" "$LOG_FILE" 2>/dev/null; then
        PORT_INFO=$(grep "Server running" "$LOG_FILE" | tail -1)
        log_success "$PORT_INFO"
    else
        log_info "Server should be running on port 3001 (or PORT from .env)"
    fi
fi

echo ""
log_info "==================================================================="
log_info "VidRip is now running in production mode"
log_info "==================================================================="
echo ""
log_info "Backend Server:"
log_info "  Running on port 3001 (or PORT from .env)"
if [ "$USE_SYSTEMD" = true ]; then
    log_info "  Mode: systemd service"
    log_info "  Service: vidrip-backend"
else
    log_info "  Mode: nohup background process"
    log_info "  PID: $SERVER_PID"
fi
echo ""
log_info "Frontend:"
log_info "  Deployed to: $WEB_ROOT"
echo ""

if [ "$USE_SYSTEMD" = true ]; then
    log_info "Service Management:"
    log_info "  Stop:    sudo systemctl stop vidrip-backend"
    log_info "  Restart: sudo systemctl restart vidrip-backend"
    log_info "  Status:  sudo systemctl status vidrip-backend"
    log_info "  Disable: sudo systemctl disable vidrip-backend"
    echo ""
    log_info "View Logs:"
    log_info "  sudo journalctl -u vidrip-backend -f"
    log_info "  tail -f $LOG_FILE"
else
    log_info "To stop the backend service:"
    log_info "  ./stop-production.sh"
    echo ""
    log_info "To view logs:"
    log_info "  tail -f $LOG_FILE"
    echo ""
    log_info "To view errors:"
    log_info "  tail -f $ERROR_LOG_FILE"
fi
echo ""
if [ -f "$SCRIPT_DIR/Caddyfile" ]; then
    log_warning "NEXT STEPS - Caddy Setup:"
    log_warning "  1. Install Caddy: https://caddyserver.com/docs/install"
    log_warning "     Quick install (Ubuntu/Debian):"
    log_warning "       sudo apt install -y debian-keyring debian-archive-keyring apt-transport-https"
    log_warning "       curl -1sLf 'https://dl.cloudsmith.io/public/caddy/stable/gpg.key' | sudo gpg --dearmor -o /usr/share/keyrings/caddy-stable-archive-keyring.gpg"
    log_warning "       curl -1sLf 'https://dl.cloudsmith.io/public/caddy/stable/debian.deb.txt' | sudo tee /etc/apt/sources.list.d/caddy-stable.list"
    log_warning "       sudo apt update && sudo apt install caddy"
    echo ""
    log_warning "  2. Copy Caddyfile to Caddy config directory:"
    log_warning "       sudo cp $SCRIPT_DIR/Caddyfile /etc/caddy/Caddyfile"
    echo ""
    log_warning "  3. Start Caddy:"
    log_warning "       sudo systemctl enable caddy"
    log_warning "       sudo systemctl start caddy"
    echo ""
    log_warning "  4. Configure firewall to allow ports 80/443:"
    log_warning "       sudo ufw allow 80/tcp"
    log_warning "       sudo ufw allow 443/tcp"
    echo ""
    log_success "Caddy will automatically obtain SSL certificates from Let's Encrypt!"
else
    log_warning "NEXT STEPS:"
    log_warning "  1. Install Caddy: https://caddyserver.com/docs/install"
    log_warning "  2. Edit Caddyfile and replace 'your-domain.com' with your domain"
    log_warning "  3. Start Caddy: sudo caddy start"
    log_warning "     (or for testing: caddy run)"
    log_warning "  4. Configure firewall to allow ports 80/443"
fi
echo ""
log_info "Alternative web servers:"
log_info "  - See DEPLOYMENT.md for nginx/Apache configurations"
echo ""

# Register cleanup on script exit
trap cleanup_on_exit EXIT

exit 0