# nginx tile cache for Martin vector tile server
# Proxy-cache layer: 10-100x faster on repeat requests, zero PostGIS load for cached tiles

proxy_cache_path /var/cache/nginx/tiles
  levels=1:2
  keys_zone=tiles:64m
  max_size=2g
  inactive=24h
  use_temp_path=off;

server {
  listen 80;
  server_name _;

  # Health check
  location = /health {
    access_log off;
    return 200 "ok\n";
    add_header Content-Type text/plain;
  }

  # Martin catalog endpoint (no cache)
  location = /catalog {
    proxy_pass http://martin:3000/catalog;
    proxy_set_header Host $host;
  }

  # Tile requests — cache aggressively
  location / {
    proxy_pass http://martin:3000;
    proxy_set_header Host $host;
    proxy_set_header X-Real-IP $remote_addr;

    # Cache config
    proxy_cache tiles;
    proxy_cache_key "$request_uri";
    proxy_cache_valid 200 1h;
    proxy_cache_valid 204 1m;
    proxy_cache_valid 404 1m;
    proxy_cache_use_stale error timeout updating http_500 http_502 http_503 http_504;
    proxy_cache_lock on;
    proxy_cache_lock_timeout 5s;

    # Pass cache status header (useful for debugging)
    add_header X-Cache-Status $upstream_cache_status always;

    # CORS headers for tile requests
    add_header Access-Control-Allow-Origin "*" always;
    add_header Access-Control-Allow-Methods "GET, HEAD, OPTIONS" always;
    add_header Access-Control-Allow-Headers "Range, If-None-Match, Accept-Encoding" always;
    add_header Access-Control-Expose-Headers "Content-Range, Content-Length, ETag, X-Cache-Status" always;

    # Handle preflight
    if ($request_method = OPTIONS) {
      add_header Access-Control-Allow-Origin "*";
      add_header Access-Control-Allow-Methods "GET, HEAD, OPTIONS";
      add_header Access-Control-Max-Age 86400;
      add_header Content-Length 0;
      return 204;
    }

    # Martin already compresses — pass through
    proxy_set_header Accept-Encoding "";
    gzip off;

    # Timeouts (Martin can be slow on low-zoom tiles)
    proxy_connect_timeout 10s;
    proxy_read_timeout 120s;
    proxy_send_timeout 30s;
  }
}