#!/bin/bash

# Data Visualization Display Wall - Systemd Installer
# Requirements: Node.js, NPM, Systemd (Linux)

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

echo -e "${BLUE}=== Data Visualization Display Wall Installer ===${NC}"

# 1. Permission check (no longer mandatory)
if [ "$EUID" -eq 0 ]; then
  # If run as sudo, get the real user that called it
  REAL_USER=${SUDO_USER:-$USER}
else
  REAL_USER=$USER
fi

# 2. Get current directory and user
PROJECT_DIR=$(pwd)
USER_HOME=$(getent passwd "$REAL_USER" | cut -d: -f6)

echo -e "Project Directory: ${GREEN}$PROJECT_DIR${NC}"
echo -e "Running User:      ${GREEN}$REAL_USER${NC}"

# 3. Check for mandatory files
if [ ! -f "server/index.js" ]; then
    echo -e "${RED}Error: server/index.js not found. Please run this script from the project root.${NC}"
    exit 1
fi

# 4. Check for dependencies
echo -e "${BLUE}Checking dependencies...${NC}"
check_dep() {
    if ! command -v "$1" &> /dev/null; then
        echo -e "${RED}$1 is not installed. Please install $1 first.${NC}"
        exit 1
    fi
}
check_dep node
check_dep npm

# 5. Check for .env file
if [ ! -f ".env" ]; then
    echo -e "${YELLOW}Warning: .env file not found.${NC}"
    if [ -f ".env.example" ]; then
        echo -e "Creating .env from .env.example..."
        cp .env.example .env
        echo -e "${GREEN}Created .env file. Please ensure values are correct.${NC}"
    else
        echo -e "${RED}Error: .env.example not found. Configuration missing.${NC}"
    fi
fi

# 6. Install NPM dependencies
echo -e "${BLUE}Installing dependencies...${NC}"
npm install

if [ $? -ne 0 ]; then
    echo -e "${RED}NPM install failed.${NC}"
    exit 1
fi

# 7. Create Systemd Service File
SERVICE_FILE="/etc/systemd/system/data-wall.service"
NODE_PATH=$(command -v node)

echo -e "${BLUE}Creating systemd service at $SERVICE_FILE... (May require password)${NC}"
sudo bash -c "cat <<EOF > '$SERVICE_FILE'
[Unit]
Description=Data Visualization Display Wall
After=network.target mysql.service redis-server.service valkey-server.service
Wants=mysql.service

[Service]
Type=simple
User=$REAL_USER
WorkingDirectory=$PROJECT_DIR
ExecStart=$NODE_PATH server/index.js
Restart=always
RestartSec=10
StandardOutput=syslog
StandardError=syslog
SyslogIdentifier=data-wall
# Pass environment via .env file injection
EnvironmentFile=-$PROJECT_DIR/.env
Environment=NODE_ENV=production

# Security Hardening
CapabilityBoundingSet=
NoNewPrivileges=true
LimitNOFILE=65535

[Install]
WantedBy=multi-user.target
EOF"

# 8. Reload Systemd and Start
echo -e "${BLUE}Reloading systemd and restarting service... (May require password)${NC}"
sudo systemctl daemon-reload
sudo systemctl enable data-wall
sudo systemctl restart data-wall

# 9. Check Status
echo -e "${BLUE}Checking service status...${NC}"
sleep 2
if sudo systemctl is-active --quiet data-wall; then
    echo -e "${GREEN}SUCCESS: Service is now running.${NC}"
    PORT=$(grep "^PORT=" .env | cut -d'=' -f2)
    PORT=${PORT:-3000}
    echo -e "Dashboard URL: ${YELLOW}http://localhost:${PORT}${NC}"
    echo -e "View logs:     ${BLUE}journalctl -u data-wall -f${NC}"
else
    echo -e "${RED}FAILED: Service failed to start.${NC}"
    echo -e "Check logs with: ${BLUE}journalctl -u data-wall -xe${NC}"
fi

# 10. Reverse Proxy Configuration
echo -ne "${YELLOW}Do you want to configure a reverse proxy (Nginx/Caddy)? (y/n): ${NC}"
read -r CONF_PROXY
if [[ "$CONF_PROXY" =~ ^[Yy]$ ]]; then
    echo -e "${BLUE}=== Reverse Proxy Configuration ===${NC}"
    
    # Get Domain
    echo -ne "Enter your domain name (e.g., monitor.example.com): "
    read -r DOMAIN
    if [ -z "$DOMAIN" ]; then
        echo -e "${RED}Error: Domain cannot be empty. Skipping proxy configuration.${NC}"
    else
        # Get Port from .env
        PORT=$(grep "^PORT=" .env | cut -d'=' -f2)
        PORT=${PORT:-3000}

        # Choose Proxy
        echo -e "Select Proxy Type:"
        echo -e "  1) Caddy (Automatic SSL, easy to use)"
        echo -e "  2) Nginx (Advanced, manual SSL)"
        echo -ne "Choose (1/2): "
        read -r PROXY_TYPE

        # Enable HTTPS?
        echo -ne "Enable HTTPS (SSL)? (y/n): "
        read -r ENABLE_HTTPS

        if [ "$PROXY_TYPE" == "1" ]; then
            # Caddy Config
            CADDY_FILE="Caddyfile"
            echo -e "${BLUE}Generating Caddyfile...${NC}"
            
            if [[ "$ENABLE_HTTPS" =~ ^[Yy]$ ]]; then
                cat <<EOF > "$CADDY_FILE"
$DOMAIN {
    reverse_proxy localhost:$PORT
}
EOF
            else
                cat <<EOF > "$CADDY_FILE"
http://$DOMAIN {
    reverse_proxy localhost:$PORT
}
EOF
            fi
            echo -e "${GREEN}Caddyfile generated at $PROJECT_DIR/$CADDY_FILE${NC}"
            echo -e "${YELLOW}Tip: Ensure Caddy is installed and pointing to this file.${NC}"
        
        elif [ "$PROXY_TYPE" == "2" ]; then
            # Nginx Config
            echo -ne "Enter Nginx configuration export path (default: ./${DOMAIN}.conf): "
            read -r NGINX_PATH
            NGINX_PATH=${NGINX_PATH:-"./${DOMAIN}.conf"}

            echo -e "${BLUE}Generating Nginx configuration...${NC}"
            
            if [[ "$ENABLE_HTTPS" =~ ^[Yy]$ ]]; then
                echo -ne "Enter SSL Certificate Path: "
                read -r SSL_CERT
                echo -ne "Enter SSL Key Path: "
                read -r SSL_KEY

                cat <<EOF > "$NGINX_PATH"
server {
    listen 80;
    server_name $DOMAIN;
    return 301 https://\$host\$request_uri;
}

server {
    listen 443 ssl http2;
    server_name $DOMAIN;

    ssl_certificate $SSL_CERT;
    ssl_certificate_key $SSL_KEY;
    
    location / {
        proxy_pass http://localhost:$PORT;
        proxy_http_version 1.1;
        proxy_set_header Upgrade \$http_upgrade;
        proxy_set_header Connection "upgrade";
        proxy_set_header Host \$host;
        proxy_set_header X-Real-IP \$remote_addr;
        proxy_set_header X-Forwarded-For \$proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto \$scheme;
    }
}
EOF
            else
                cat <<EOF > "$NGINX_PATH"
server {
    listen 80;
    server_name $DOMAIN;

    location / {
        proxy_pass http://localhost:$PORT;
        proxy_http_version 1.1;
        proxy_set_header Upgrade \$http_upgrade;
        proxy_set_header Connection "upgrade";
        proxy_set_header Host \$host;
        proxy_set_header X-Real-IP \$remote_addr;
        proxy_set_header X-Forwarded-For \$proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto \$scheme;
    }
}
EOF
            fi
            echo -e "${GREEN}Nginx config generated at $NGINX_PATH${NC}"
            echo -e "${YELLOW}Tip: You can symlink this to /etc/nginx/sites-enabled/ to activate.${NC}"
        else
            echo -e "${YELLOW}Unknown proxy type selected. Skipping.${NC}"
        fi
    fi
fi

echo -e "${BLUE}================================================${NC}"
echo -e "${GREEN}Setup completed successfully!${NC}"