http {
  # Misc nginx config

  # LUA library paths.  Ensure that cjson.so and lua-resty are available.
  lua_package_path   '/Users/chirayu/ck/vcs/ck_3p/lib/lua/?.lua;/Users/chirayu/ck/vcs/ck5/lua/?.lua;;';
  lua_package_cpath  '/Users/chirayu/ck/vcs/ck_3p/lib/lua/?.so;;';

  init_by_lua '
    ck_nginx_main = require "ck.nginx.main"
    ck_nginx_main.config.HOME_PATH = "/Users/chirayu/"
    ck_nginx_main.config.WEB_ROOT = "/etc/ck/web_roots"
    ck_nginx_main.config.IMPLICIT_WEBROOTS_ENABLED = true
  ';

  server {
      server_name ~^(?<ck_subdomain>.*)\.(localhost|cheshire\.local\.c-k\.me)$
                  ~^(?<ck_domain>.*\..*)$ ;
      listen          [::1]:80;
      listen          127.0.0.1:80;

      # Example:
      #
      #    redis-cli hset ck.config.local.subdomain sample.dart.app '{"type": "proxy", "port": 6060}'

      location @proxy_pass {
          # Pre-req: Must set $proxy_port
          proxy_cache off;
          proxy_pass_header Server;
          #ckck proxy_pass_header Connection;  # ckck
          #ckck proxy_pass_header Upgrade;  # ckck

          # It's better to use $host instead of $http_host.  It's equal to
          # the value of $http_host (the name of the server in the
          # request-header), but when there is no such header, it's equal to
          # the name of the nginx server instead of being blank.
          proxy_set_header  Host $host;

          proxy_redirect    off;
          proxy_set_header  X-Real-IP $remote_addr;
          proxy_set_header  X-Forwarded-For $proxy_add_x_forwarded_for;
          proxy_set_header  X-Scheme $scheme;
          proxy_connect_timeout      90;
          proxy_send_timeout         90;
          proxy_read_timeout         90;
          proxy_send_lowat           12000;

          # To support websocket proxying.
          proxy_buffering off;
          # proxy_buffer_size          4k;
          # proxy_buffers              4 32k;
          # proxy_busy_buffers_size    64k;

          # proxy_temp_file_write_size 64k;
          proxy_pass        http://127.0.0.1:$ck_proxy_port;

          # WebSockets also proxied.
          # Ref: http://nginx.org/en/docs/http/websocket.html
          # Requires nginx 1.3.13+
          proxy_http_version 1.1;
          proxy_set_header Upgrade $http_upgrade;
          # TODO(chirayu): Is there any point to using the
          # $connection_upgrade map here?  Passing $http_connection through
          # appears to work fine.
          # proxy_set_header Connection $connection_upgrade;
          proxy_set_header Connection $http_connection;
      }

      location @link {
          root $ck_link_root;
          default_type application/octet-stream;
          # Ref: http://nginx.org/en/docs/http/ngx_http_autoindex_module.html
          autoindex on;  # Show directory listings.
          autoindex_exact_size off;  # Display human readable sizes.
      }

      location @wsgi {
          # Needs --reload-os-env on uwsgi.
          # Ref: http://uwsgi.readthedocs.org/en/latest/features/magic-variables.html
          uwsgi_param UWSGI_SETENV CK_PATH_PREFIX=/;
          uwsgi_param SCRIPT_NAME /;
          uwsgi_param UWSGI_MODULE ck.web.wsgi_apps.$ck_wsgi_name;
          uwsgi_param UWSGI_CALLABLE wsgi_app;
          uwsgi_modifier1 30; # properly sets PATH_INFO
          uwsgi_modifier2 0;
          uwsgi_pass uwsgi_vhost_on_nginx;
          include /etc/ck/customize/nginx/uwsgi_params;
      }


      location / {
          set $ck_proxy_port -1 ;
          set $ck_link_root "" ;
          set $ck_wsgi_name "" ;
          rewrite_by_lua 'ck_nginx_main.rewrite()';
      }
  }
}

do
  local ngx   = require("ngx")
  local cjson = require("cjson")
  local redis = require("resty.redis")

  local API_CONFIG = {
    HOME_PATH = "/Users/chirayu/",
    WEB_ROOT = "/Users/chirayu/z/web_roots/",
    IMPLICIT_WEBROOTS_ENABLED = false,
  }

  local function _SubdomainHandler_NewFields()
    return { red = nil }
  end

  local _SubdomainHandler = _SubdomainHandler_NewFields()

  function _SubdomainHandler:new()
    local result = _SubdomainHandler_NewFields()
    setmetatable(result, self)
    self.__index = self
    -- self.__newindex = self
    return result
  end

  function _SubdomainHandler:_get_redis()
    if self.red ~= nil then return self.red end
    local red = redis:new()
    red:set_timeout(1000) -- 1 sec
    local ok, err = red:connect("127.0.0.1", 6379)
    if not ok then return nil end
    self.red = red
    return self.red
  end

  function _SubdomainHandler:_close_redis()
    if self.red ~= nil then
      -- put it into the connection pool of size 100,
      -- with 0 idle timeout
      local ok, err = self.red:set_keepalive(0, 100)
      self.red = nil
    end
  end

  function _SubdomainHandler:_bail(message)
    self:_close_redis()
    ngx.status = ngx.HTTP_NOT_FOUND;
    ngx.header["Content-Type"] = "text/plain";
    ngx.say(message)
    return ngx.exit(ngx.HTTP_NOT_FOUND);
  end

  function _SubdomainHandler:_lookup_subdomain(subdomain)
    local json = self.red:hget("ck.config.local.subdomain", subdomain)
    if not json or json == ngx.null then
      return nil, self:_bail("Could not lookup ck.config.local.subdomain:" .. subdomain)
    end

    local config = cjson.decode(json)
    return config, nil
  end

  function _SubdomainHandler:rewrite(domain_key)
    local red = self:_get_redis()
    if not red then
      return self:_bail("Could not connect to redis")
    end

    local config, err = self:_lookup_subdomain(domain_key)
    if err then return err end

    if type(config) == "string" then
      config, err = self:_lookup_subdomain(config)
      if err then return err end
    end

    self:_close_redis()

    if config.type == "proxy" then
      ngx.var.ck_proxy_port = config.port
      return ngx.exec("@proxy_pass")
    elseif config.type == "link" then
      if config.root ~= nil then
        if string.sub(config.root, 1, 2) == "~/" then
          ngx.var.ck_link_root = API_CONFIG.HOME_PATH .. string.sub(config.root, 3)
        else
          ngx.var.ck_link_root = config.root
        end
      else
        if API_CONFIG.IMPLICIT_WEBROOTS_ENABLED then
          ngx.var.ck_link_root = API_CONFIG.WEB_ROOT .. domain_key
        else
          return self:_bail("Implicit web_roots disabled on this host.  - chirayu")
        end
      end
      return ngx.exec("@link")
    elseif config.type == "wsgi" then
      ngx.var.ck_wsgi_name = domain_key
      return ngx.exec("@wsgi")
    else
      return self:_bail("Unknown subdomain type:" .. config.type)
    end

  end

  return {
    config = API_CONFIG,
    rewrite = function()
        local domain_key = ngx.var["ck_subdomain"]
        if domain_key == nil then
          -- make absolute domain for lookup
          domain_key = ngx.var["ck_domain"] .. "."
        end
        return _SubdomainHandler:new():rewrite(domain_key)
      end
  }

end