-- Helper Functions
function file_exists(path)
   local attr = lighty.stat(path)
   if (attr and attr["is_file"]) then
      return true
   else
      return false
   end
end

function removePrefix(str, prefix)
   return str:sub(1,#prefix+1) == prefix.."/" and str:sub(#prefix+2)
end

function string.starts(x,y)
   return string.sub(x,1,string.len(y)) == y
end

-- Set for subdirectory drupal installs. Example: "/drupal"
local prefix = ''

-- If this is not an existing file
if (not file_exists(lighty.env["physical.path"])) then

  -- Set local variables
  local FINAL_PATH = "empty"
  local request_uri = removePrefix(lighty.env["uri.path"], prefix) -- none should be set to '/'
  local query_string = lighty.env["uri.query"]
	local cookies = lighty.request["Cookie"] or "NOCOOKIE"
  --print ("URI "..request_uri)

  -- filters for boost cache (anon+GET) to qualify boost caching
  local SERVE_CACHED_FLAG = (string.find(cookies, "DRUPAL_UID") == nil) and (lighty.env["request.method"] == "GET")
  local RESTRICTED_PATHS = (string.starts(request_uri, "/admin"))
                or (string.starts(request_uri, "/cache"))
                or (string.starts(request_uri, "/openid"))
                or (string.starts(request_uri, "/node/add"))
                or (string.starts(request_uri, "/user"))

  -- qualifies for boost cache type
  if (SERVE_CACHED_FLAG == true and RESTRICTED_PATHS == false) then

		-- Build filename based on URL for the boost cache
    local normal_boost_path_uribase = lighty.env["physical.doc-root"] .. prefix .. "/cache/normal/" .. lighty.request["Host"] .. "/" .. request_uri .. "_"
    local normal_gzip_boost_path_uribase = lighty.env["physical.doc-root"] .. prefix .. "/cache/normal/" .. lighty.request["Host"] .. "/" .. request_uri .. "_"
    local perm_boost_path_uribase = lighty.env["physical.doc-root"] .. prefix .. "/cache/perm/" .. lighty.request["Host"] .. "/" .. request_uri .. "_"
    local perm_gzip_boost_path_uribase = lighty.env["physical.doc-root"] .. prefix .. "/cache/perm/" .. lighty.request["Host"] .. "/" .. request_uri .. "_"
    if (query_string) then
      normal_boost_path_uribase = normal_boost_path_uribase ..  query_string
      normal_gzip_boost_path_uribase = normal_gzip_boost_path_uribase .. query_string
    end

    -- Set Final Path, Content-Type & Content-Encoding if this file exists.
    if (string.find(lighty.request["Accept-Encoding"], "gzip") or string.find(cookies, "boost-gzip"))
      -- Try gzip first
      if (file_exists(normal_gzip_boost_path_uribase .. ".html.gz")) then
        FINAL_PATH = normal_gzip_boost_path_uribase .. ".html.gz"
        lighty.header["Content-Encoding"] = "gzip"
        lighty.header["Content-Type"] = "text/html"
      elseif (file_exists(perm_gzip_boost_path_uribase .. ".css.gz")) then
        FINAL_PATH = perm_gzip_boost_path_uribase .. ".css.gz"
        lighty.header["Content-Encoding"] = "gzip"
        lighty.header["Content-Type"] = "text/css"
      elseif (file_exists(perm_gzip_boost_path_uribase .. ".js.gz")) then
        FINAL_PATH = perm_gzip_boost_path_uribase .. ".js.gz"
        lighty.header["Content-Encoding"] = "gzip"
        lighty.header["Content-Type"] = "text/javascript"
      elseif (file_exists(normal_gzip_boost_path_uribase .. ".xml.gz")) then
        FINAL_PATH = normal_gzip_boost_path_uribase .. ".xml.gz"
        lighty.header["Content-Encoding"] = "gzip"
        lighty.header["Content-Type"] = "text/xml"
      elseif (file_exists(normal_gzip_boost_path_uribase .. ".json.gz")) then
        FINAL_PATH = normal_gzip_boost_path_uribase .. ".json.gz"
        lighty.header["Content-Encoding"] = "gzip"
        lighty.header["Content-Type"] = "text/javascript"
      end
    else
      if (file_exists(normal_boost_path_uribase .. ".html")) then
        FINAL_PATH = normal_boost_path_uribase .. ".html"
        lighty.header["Content-Type"] = "text/html"
      elseif (file_exists(perm_boost_path_uribase .. ".css")) then
        FINAL_PATH = perm_boost_path_uribase .. ".html"
        lighty.header["Content-Type"] = "text/css"
      elseif (file_exists(perm_boost_path_uribase .. ".js")) then
        FINAL_PATH = perm_boost_path_uribase .. ".html"
        lighty.header["Content-Type"] = "text/javascript"
      elseif (file_exists(normal_boost_path_uribase .. ".xml")) then
        FINAL_PATH = normal_boost_path_uribase .. ".html"
        lighty.header["Content-Type"] = "text/xml"
      elseif (file_exists(normal_boost_path_uribase .. ".json")) then
        FINAL_PATH = normal_boost_path_uribase .. ".html"
        lighty.header["Content-Type"] = "text/javascript"
    end

  -- Aggressive gzip cookie test
  elseif (request_uri == "/boost-gzip-cookie-test.html") then
    FINAL_PATH = lighty.env["physical.doc-root"] .. prefix .. "/cache/perm/boost-gzip-cookie-test.html.gz"
		lighty.header["Content-Encoding"] = "gzip"
		lighty.header["Content-Type"] = "text/html"
	end

  -- File not in cache. pass it to the fastcgi backend
  if (FINAL_PATH == "empty") then       
    lighty.env["uri.path"] = prefix .. "/index.php"
    lighty.env["uri.query"] = query_string .. (query_string ~= "" and "&" or "") .. "q=" .. request_uri
    lighty.env["physical.rel-path"] = lighty.env["uri.path"]
    lighty.env["request.orig-uri"] = lighty.env["request.uri"]
    FINAL_PATH = lighty.env["physical.doc-root"] .. lighty.env["physical.rel-path"]
  else
    -- Set Boost Headers
    lighty.header["X-Header"] = "Boost Citrus 1.7"
    lighty.header["Expires"] = "Sun, 19 Nov 1978 05:00:00 GMT"
    lighty.header["Cache-Control"] = "no-store, no-cache, must-revalidate, post-check=0, pre-check=0"
  end

  --print("Final Path Query "..lighty.env["uri.query"])
  lighty.env["physical.path"] = FINAL_PATH
end