# ==============================================================================
# CheckIn App V2 - Nginx Configuration Example
# ==============================================================================
#
# Usage:
#   1. Copy this file: sudo cp nginx.conf.example /etc/nginx/sites-available/checkin-app
#   2. Edit the file and replace placeholders with your actual values
#   3. Create symlink: sudo ln -s /etc/nginx/sites-available/checkin-app /etc/nginx/sites-enabled/
#   4. Test config: sudo nginx -t
#   5. Reload Nginx: sudo systemctl reload nginx
#
# ==============================================================================

# Upstream backend API server
upstream checkin_backend {
    # Backend FastAPI server running on port 8000
    server 127.0.0.1:8000;

    # Optional: Add more backend servers for load balancing
    # server 127.0.0.1:8001;
    # server 127.0.0.1:8002;

    # Keep alive connections
    keepalive 32;
}

# HTTP Server - Redirect to HTTPS (optional)
server {
    listen 80;
    listen [::]:80;
    server_name your-domain.com www.your-domain.com;

    # Redirect all HTTP traffic to HTTPS
    return 301 https://$server_name$request_uri;
}

# HTTPS Server
server {
    # SSL Configuration
    listen 443 ssl http2;
    listen [::]:443 ssl http2;
    server_name your-domain.com www.your-domain.com;

    # SSL Certificate (Let's Encrypt recommended)
    ssl_certificate /etc/letsencrypt/live/your-domain.com/fullchain.pem;
    ssl_certificate_key /etc/letsencrypt/live/your-domain.com/privkey.pem;

    # SSL Configuration (Modern)
    ssl_protocols TLSv1.2 TLSv1.3;
    ssl_ciphers 'ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384';
    ssl_prefer_server_ciphers off;
    ssl_session_cache shared:SSL:10m;
    ssl_session_timeout 10m;

    # Security Headers
    add_header Strict-Transport-Security "max-age=31536000; includeSubDomains" always;
    add_header X-Frame-Options "SAMEORIGIN" always;
    add_header X-Content-Type-Options "nosniff" always;
    add_header X-XSS-Protection "1; mode=block" always;

    # Root directory for frontend static files
    root /opt/checkin-app/frontend/dist;
    index index.html;

    # Access and Error Logs
    access_log /var/log/nginx/checkin-app-access.log;
    error_log /var/log/nginx/checkin-app-error.log;

    # Gzip Compression
    gzip on;
    gzip_vary on;
    gzip_min_length 1024;
    gzip_types text/plain text/css text/xml text/javascript application/x-javascript application/xml+rss application/json application/javascript;

    # Client body size (for file uploads)
    client_max_body_size 10M;

    # ==========================================
    # API Proxy Configuration
    # ==========================================
    location /api/ {
        # Proxy to backend
        proxy_pass http://checkin_backend;

        # Proxy headers
        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;

        # WebSocket support (if needed)
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "upgrade";

        # Timeouts
        proxy_connect_timeout 60s;
        proxy_send_timeout 60s;
        proxy_read_timeout 60s;

        # Buffering
        proxy_buffering off;
        proxy_request_buffering off;
    }

    # API Documentation
    location /docs {
        proxy_pass http://checkin_backend;
        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;
    }

    location /redoc {
        proxy_pass http://checkin_backend;
        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;
    }

    location /openapi.json {
        proxy_pass http://checkin_backend;
        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;
    }

    # ==========================================
    # Frontend Static Files
    # ==========================================

    # Cache static assets
    location ~* \.(js|css|png|jpg|jpeg|gif|ico|svg|woff|woff2|ttf|eot)$ {
        expires 1y;
        add_header Cache-Control "public, immutable";
        try_files $uri =404;
    }

    # Frontend routes (SPA)
    location / {
        try_files $uri $uri/ /index.html;
        add_header Cache-Control "no-cache, no-store, must-revalidate";
    }

    # Favicon
    location = /favicon.ico {
        log_not_found off;
        access_log off;
    }

    # Robots.txt
    location = /robots.txt {
        log_not_found off;
        access_log off;
    }

    # Health check endpoint
    location /health {
        proxy_pass http://checkin_backend;
        access_log off;
    }
}

# ==============================================================================
# Alternative: HTTP-only configuration (for development/internal use)
# ==============================================================================
# Uncomment below if you don't need HTTPS

# server {
#     listen 80;
#     listen [::]:80;
#     server_name your-domain.com;
#
#     root /opt/checkin-app/frontend/dist;
#     index index.html;
#
#     access_log /var/log/nginx/checkin-app-access.log;
#     error_log /var/log/nginx/checkin-app-error.log;
#
#     gzip on;
#     gzip_types text/plain text/css application/json application/javascript text/xml application/xml application/xml+rss text/javascript;
#
#     client_max_body_size 10M;
#
#     # API Proxy
#     location /api/ {
#         proxy_pass http://127.0.0.1:8000;
#         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;
#         proxy_http_version 1.1;
#         proxy_buffering off;
#     }
#
#     # API Documentation
#     location ~ ^/(docs|redoc|openapi.json) {
#         proxy_pass http://127.0.0.1:8000;
#         proxy_set_header Host $host;
#         proxy_set_header X-Real-IP $remote_addr;
#     }
#
#     # Static files
#     location ~* \.(js|css|png|jpg|jpeg|gif|ico|svg)$ {
#         expires 1y;
#         add_header Cache-Control "public";
#     }
#
#     # Frontend routes
#     location / {
#         try_files $uri $uri/ /index.html;
#     }
# }