<% require 'uri' %>
# DO NOT EDIT - This file is being maintained by Chef
location ~* "^/layer/<%= @layer %>/(\d+)/(\d+)/(\d+)\.(jpg|jpeg|png|webp)$" {
  # keep captures in variables for use in the named location
  set $z   $1;
  set $x   $2;
  set $y   $3;
  set $ext $4;

  # Serve local file if present; otherwise jump to proxy
  try_files /layer/<%= @layer %>/$z/$x/$y.jpg /layer/<%= @layer %>/$z/$x/$y.jpeg /layer/<%= @layer %>/$z/$x/$y.png /layer/<%= @layer %>/$z/$x/$y.webp @tile_backend;

  # Return transparent PNG for HTTP 204 (no content) responses from backend
  error_page 204 =200 /transparent.png;

  gzip off;
  expires 31d;
  add_header Cache-Control "stale-while-revalidate=2678400, stale-if-error=2678400";
  add_header x-cache-status $upstream_cache_status;
  add_header 'Access-Control-Allow-Origin' '*' always;
}

location @tile_backend {
  internal;

<% if @uses_tiler -%>
  set $upstream_uri /mosaicjson/tiles/WebMercatorQuad/$z/$x/$y@1x.$ext?url=<%= URI.encode_www_form_component(@source) %>&pixel_selection=first;

  proxy_pass http://<%= @site %>_tiler_backend$upstream_uri;
  proxy_set_header Host $host;
  proxy_set_header Referer $http_referer;
  proxy_set_header X-Forwarded-For $remote_addr;
  proxy_set_header X-Forwarded-Proto https;
  proxy_set_header X-Forwarded-SSL on;
  proxy_http_version 1.1;
  proxy_set_header Connection "";
  proxy_set_header Cache-Control "";
  proxy_set_header Pragma "";
  proxy_redirect off;

  proxy_cache_key "<%= @layer %><%= @revision %> $request_method $z $x $y $ext";
  proxy_cache proxy_cache_zone;
  proxy_cache_valid 200 204 180d;
  proxy_cache_use_stale error timeout updating http_502 http_503 http_504;
  proxy_cache_background_update on;

  proxy_next_upstream error timeout invalid_header http_500 http_503;
  proxy_next_upstream_timeout 30s;
  proxy_next_upstream_tries 3;

  proxy_intercept_errors on;
  proxy_ignore_headers "Cache-Control";
  proxy_ignore_headers "Expires";
  proxy_hide_header "Cache-Control";
  proxy_hide_header "Expires";
  proxy_hide_header "Access-Control-Allow-Origin";
  proxy_hide_header "Content-BBOX";
  proxy_hide_header "Content-CRS";
<% else -%>
  # Override QUERY_STRING to force mapserver query parameters
  fastcgi_param QUERY_STRING "map=/srv/imagery/mapserver/layer-<%= @layer %>.map&mode=tile&layers=<%= @layer %>&tilemode=gmap&tile=$x+$y+$z";
  fastcgi_pass "<%= @site %>_fastcgi";
  include fastcgi_params;
  fastcgi_param REQUEST_METHOD "GET";
  fastcgi_param HTTP_PROXY "";
  fastcgi_read_timeout 60s;

  # Caching
  fastcgi_cache "fastcgi_cache_zone";
  fastcgi_cache_key "<%= @layer %><%= @revision %> $request_method $z $x $y";

  # Free connection to socket for other requests
  fastcgi_keep_conn off;

  fastcgi_cache_valid 200 21d;

  # Serve stale cache on errors or if updating
  fastcgi_cache_use_stale error timeout updating http_500 http_503;
  # If in cache as stale, serve stale and update in background
  fastcgi_cache_background_update on;
  # Enable revalidation using If-Modified-Since and If-None-Match for stale items
  fastcgi_cache_revalidate on;

  keepalive_requests 0;

  fastcgi_catch_stderr "Image handling error";

  fastcgi_next_upstream error timeout invalid_header http_500 http_503;
  fastcgi_next_upstream_tries 8;
<% end -%>
  gzip off;
  expires 31d;
  add_header Cache-Control "stale-while-revalidate=2678400, stale-if-error=2678400";
  add_header x-cache-status $upstream_cache_status;
  add_header 'Access-Control-Allow-Origin' '*' always;
}

<% if @root_layer -%>
rewrite "^/(\d+)/(\d+)/(\d+)\.(jpg|jpeg|png|webp)$" "/layer/<%= @layer %>/$1/$2/$3.$4" last;
<% end -%>
<% @url_aliases.each do |url| -%>
rewrite "^<%= url %>/(\d+)/(\d+)/(\d+)\.(jpg|jpeg|png|webp)$" "/layer/<%= @layer %>/$1/$2/$3.$4" last;
<% end -%>