# Nginx反向代理配置 - 用于生产环境
# 将此文件复制到 /etc/nginx/sites-available/chatapp
# 然后创建软链接: sudo ln -s /etc/nginx/sites-available/chatapp /etc/nginx/sites-enabled/

upstream backend {
    server localhost:5000;
    keepalive 32;
}

upstream frontend {
    server localhost:3000;
    keepalive 32;
}

# HTTP重定向到HTTPS
server {
    listen 80;
    server_name your-domain.com www.your-domain.com;
    
    # Let's Encrypt验证
    location /.well-known/acme-challenge/ {
        root /var/www/html;
    }
    
    # 重定向到HTTPS
    location / {
        return 301 https://$server_name$request_uri;
    }
}

# HTTPS配置
server {
    listen 443 ssl http2;
    server_name your-domain.com www.your-domain.com;
    
    # SSL证书配置
    ssl_certificate /etc/letsencrypt/live/your-domain.com/fullchain.pem;
    ssl_certificate_key /etc/letsencrypt/live/your-domain.com/privkey.pem;
    
    # SSL安全配置
    ssl_protocols TLSv1.2 TLSv1.3;
    ssl_ciphers ECDHE-RSA-AES256-GCM-SHA512:DHE-RSA-AES256-GCM-SHA512:ECDHE-RSA-AES256-GCM-SHA384:DHE-RSA-AES256-GCM-SHA384;
    ssl_prefer_server_ciphers off;
    ssl_session_cache shared:SSL:10m;
    ssl_session_timeout 10m;
    
    # 安全头
    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;
    add_header Referrer-Policy "strict-origin-when-cross-origin" always;
    
    # 日志配置
    access_log /var/log/nginx/chatapp_access.log;
    error_log /var/log/nginx/chatapp_error.log;
    
    # 客户端配置
    client_max_body_size 10M;
    client_body_timeout 60s;
    client_header_timeout 60s;
    
    # API代理
    location /api/ {
        proxy_pass http://backend;
        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;
        proxy_cache_bypass $http_upgrade;
        proxy_connect_timeout 30s;
        proxy_send_timeout 30s;
        proxy_read_timeout 30s;
    }
    
    # Socket.IO代理
    location /socket.io/ {
        proxy_pass http://backend;
        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;
        proxy_cache_bypass $http_upgrade;
        proxy_connect_timeout 30s;
        proxy_send_timeout 30s;
        proxy_read_timeout 86400s;  # 24小时，用于长连接
    }
    
    # 前端代理
    location / {
        proxy_pass http://frontend;
        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;
        proxy_cache_bypass $http_upgrade;
        proxy_connect_timeout 30s;
        proxy_send_timeout 30s;
        proxy_read_timeout 30s;
    }
    
    # 静态资源缓存
    location ~* \.(js|css|png|jpg|jpeg|gif|ico|svg|woff|woff2|ttf|eot)$ {
        proxy_pass http://frontend;
        expires 1y;
        add_header Cache-Control "public, immutable";
        add_header Vary "Accept-Encoding";
    }
    
    # Gzip压缩
    gzip on;
    gzip_vary on;
    gzip_min_length 1024;
    gzip_proxied any;
    gzip_comp_level 6;
    gzip_types
        text/plain
        text/css
        text/xml
        text/javascript
        application/javascript
        application/xml+rss
        application/json
        application/xml
        image/svg+xml;
}