worker_processes auto;
error_log /var/log/nginx/error.log warn;
pid /var/run/nginx.pid;

events {
    worker_connections 1024;
}

http {
    include /etc/nginx/mime.types;
    default_type application/octet-stream;

    log_format main '$remote_addr - $remote_user [$time_local] "$request" '
                    '$status $body_bytes_sent "$http_referer" '
                    '"$http_user_agent" "$http_x_forwarded_for"';

    access_log /var/log/nginx/access.log main;

    sendfile on;
    tcp_nopush on;
    keepalive_timeout 65;
    gzip on;
    gzip_types text/plain application/json application/javascript;
    client_max_body_size 10m;

    # Rate limiting
    limit_req_zone $binary_remote_addr zone=api:10m rate=30r/s;
    limit_req_zone $binary_remote_addr zone=auth:10m rate=5r/s;

    # Upstream definitions - using K8s service DNS names
    # keepalive enables persistent connections to reduce latency
    upstream user_service {
        server user-service.warmcheck.svc.cluster.local:8081;
        keepalive 16;
    }

    upstream interaction_service {
        server interaction-service.warmcheck.svc.cluster.local:8082;
        keepalive 16;
    }

    upstream social_service {
        server social-service.warmcheck.svc.cluster.local:8083;
        keepalive 8;
    }

    upstream push_service {
        server push-service.warmcheck.svc.cluster.local:8084;
        keepalive 8;
    }

    upstream ws_gateway {
        server gateway.warmcheck.svc.cluster.local:8085;
    }

    upstream admin_service {
        server admin-service.warmcheck.svc.cluster.local:8086;
        keepalive 4;
    }

    # HTTPS server - for external access via HK CVM nginx
    server {
        listen 443 ssl;
        server_name api.warmcheck.app;

        ssl_certificate /etc/nginx/ssl/tls.crt;
        ssl_certificate_key /etc/nginx/ssl/tls.key;
        ssl_protocols TLSv1.2 TLSv1.3;
        ssl_ciphers HIGH:!aNULL:!MD5;
        ssl_prefer_server_ciphers on;
        ssl_session_cache shared:SSL:10m;
        ssl_session_timeout 10m;

        # Health check
        location /health {
            return 200 '{"status":"ok","gateway":"nginx","ssl":true}';
            add_header Content-Type application/json;
        }

        # Auth routes (stricter rate limit)
        location /auth/ {
            limit_req zone=auth burst=10 nodelay;
            proxy_pass http://user_service;
            proxy_http_version 1.1;
            proxy_set_header Connection "";
            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_connect_timeout 5s;
            proxy_read_timeout 15s;
            proxy_send_timeout 10s;
        }

        # User service routes
        location ~ ^/api/v1/(user|sign|growth|museum|feedback)(/|$) {
            limit_req zone=api burst=20 nodelay;
            proxy_pass http://user_service;
            proxy_http_version 1.1;
            proxy_set_header Connection "";
            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_connect_timeout 5s;
            proxy_read_timeout 15s;
            proxy_send_timeout 10s;
        }

        # User service routes (emergency contact)
        location ~ ^/api/v1/users/ {
            limit_req zone=api burst=20 nodelay;
            proxy_pass http://user_service;
            proxy_http_version 1.1;
            proxy_set_header Connection "";
            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_connect_timeout 5s;
            proxy_read_timeout 15s;
            proxy_send_timeout 10s;
        }

        # Interaction service routes
        location ~ ^/api/v1/(story-card|care-card|urgent-care)/ {
            limit_req zone=api burst=20 nodelay;
            proxy_pass http://interaction_service;
            proxy_http_version 1.1;
            proxy_set_header Connection "";
            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_connect_timeout 5s;
            proxy_read_timeout 15s;
            proxy_send_timeout 10s;
        }

        # Social service routes
        location ~ ^/api/v1/(magnet|chat)/ {
            limit_req zone=api burst=20 nodelay;
            proxy_pass http://social_service;
            proxy_http_version 1.1;
            proxy_set_header Connection "";
            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_connect_timeout 5s;
            proxy_read_timeout 15s;
            proxy_send_timeout 10s;
        }

        # Push service routes
        location ~ ^/api/v1/notification/ {
            limit_req zone=api burst=20 nodelay;
            proxy_pass http://push_service;
            proxy_http_version 1.1;
            proxy_set_header Connection "";
            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_connect_timeout 5s;
            proxy_read_timeout 15s;
            proxy_send_timeout 10s;
        }

        # Admin service routes (report & feedback submission from app)
        location ~ ^/api/v1/(report|feedback)$ {
            limit_req zone=api burst=20 nodelay;
            proxy_pass http://admin_service;
            proxy_http_version 1.1;
            proxy_set_header Connection "";
            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_connect_timeout 5s;
            proxy_read_timeout 15s;
            proxy_send_timeout 10s;
        }

        # WebSocket gateway
        location /ws {
            proxy_pass http://ws_gateway;
            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_read_timeout 86400;
        }

        # AI service routes
        location /ai/ {
            limit_req zone=api burst=10 nodelay;
            proxy_pass http://ai-service.warmcheck.svc.cluster.local:5001;
            proxy_set_header Host $host;
            proxy_set_header X-Real-IP $remote_addr;
            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        }

        # Analytics service routes
        location /analytics/ {
            limit_req zone=api burst=10 nodelay;
            proxy_pass http://analytics-service.warmcheck.svc.cluster.local:5003;
            proxy_set_header Host $host;
            proxy_set_header X-Real-IP $remote_addr;
            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        }

        # Admin service routes (UI + API)
        location /admin {
            proxy_pass http://admin_service;
            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;
        }
    }

    # HTTP server - for internal health checks and backward compatibility
    server {
        listen 80;
        server_name api.warmcheck.app;

        # Health check
        location /health {
            return 200 '{"status":"ok","gateway":"nginx"}';
            add_header Content-Type application/json;
        }

        # Auth routes (stricter rate limit)
        location /auth/ {
            limit_req zone=auth burst=10 nodelay;
            proxy_pass http://user_service;
            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;
        }

        # User service routes (feedback uses exact path without trailing slash)
        location ~ ^/api/v1/(user|sign|growth|museum|feedback)(/|$) {
            limit_req zone=api burst=20 nodelay;
            proxy_pass http://user_service;
            proxy_set_header Host $host;
            proxy_set_header X-Real-IP $remote_addr;
            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        }

        # User service routes (emergency contact)
        location ~ ^/api/v1/users/ {
            limit_req zone=api burst=20 nodelay;
            proxy_pass http://user_service;
            proxy_set_header Host $host;
            proxy_set_header X-Real-IP $remote_addr;
            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        }

        # Interaction service routes
        location ~ ^/api/v1/(story-card|care-card|urgent-care)/ {
            limit_req zone=api burst=20 nodelay;
            proxy_pass http://interaction_service;
            proxy_set_header Host $host;
            proxy_set_header X-Real-IP $remote_addr;
            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        }

        # Social service routes
        location ~ ^/api/v1/(magnet|chat)/ {
            limit_req zone=api burst=20 nodelay;
            proxy_pass http://social_service;
            proxy_set_header Host $host;
            proxy_set_header X-Real-IP $remote_addr;
            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        }

        # Push service routes
        location ~ ^/api/v1/notification/ {
            limit_req zone=api burst=20 nodelay;
            proxy_pass http://push_service;
            proxy_set_header Host $host;
            proxy_set_header X-Real-IP $remote_addr;
            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        }

        # Admin service routes (report & feedback submission from app)
        location ~ ^/api/v1/(report|feedback)$ {
            limit_req zone=api burst=20 nodelay;
            proxy_pass http://admin_service;
            proxy_set_header Host $host;
            proxy_set_header X-Real-IP $remote_addr;
            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        }

        # WebSocket gateway
        location /ws {
            proxy_pass http://ws_gateway;
            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_read_timeout 86400;
        }

        # AI service routes
        location /ai/ {
            limit_req zone=api burst=10 nodelay;
            proxy_pass http://ai-service.warmcheck.svc.cluster.local:5001;
            proxy_set_header Host $host;
            proxy_set_header X-Real-IP $remote_addr;
            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        }

        # Analytics service routes
        location /analytics/ {
            limit_req zone=api burst=10 nodelay;
            proxy_pass http://analytics-service.warmcheck.svc.cluster.local:5003;
            proxy_set_header Host $host;
            proxy_set_header X-Real-IP $remote_addr;
            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        }

        # Admin service routes (UI + API)
        location /admin {
            proxy_pass http://admin_service;
            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;
        }
    }
}