# Docker DNS resolver (127.0.0.11 = Docker's embedded DNS).
# Required for variable-based proxy_pass below to resolve upstream
# hostnames on each request instead of caching them at startup.
# Without this, when backend containers are recreated (new IP),
# nginx keeps pointing to stale IPs → 502 Bad Gateway.
# Valid=10s re-resolves at most every 10 seconds to avoid excessive DNS queries.
resolver 127.0.0.11 ipv6=off valid=10s;

map $http_upgrade $connection_upgrade {
    default upgrade;
    ''      close;
}

server {
    listen 80;
    server_name imphnen.asepharyana.my.id;

    # API proxy — matches /api and /api/*
    location ^~ /api {
        set $backend_url "http://backend:3000";
        proxy_pass $backend_url$uri$is_args$args;
        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 proxy — matches /ws and /ws/*
    location ^~ /ws {
        set $backend_url "http://backend:3000";
        proxy_pass $backend_url$uri$is_args$args;
        proxy_http_version 1.1;
        proxy_set_header Upgrade              $http_upgrade;
        proxy_set_header Connection           $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;

        # WebSocket-specific: no buffering, longer timeouts
        proxy_buffering off;
        proxy_read_timeout 86400s;
        proxy_send_timeout 86400s;
    }

    # Gzip for static assets
    gzip on;
    gzip_types text/plain text/css application/json application/javascript application/wasm image/svg+xml;
    gzip_min_length 256;

    # Cache static assets (JS/WASM hashed filenames)
    location /assets/ {
        root /usr/share/nginx/html;
        expires 1y;
        add_header Cache-Control "public, immutable";
    }

    # Frontend SPA fallback — serve static files directly
    location / {
        root /usr/share/nginx/html;
        index index.html;
        try_files $uri $uri/ /index.html;
    }
}