-- Copyright (C) 2010 John Millikin <jmillikin@gmail.com>
-- 
-- This program is free software: you can redistribute it and/or modify
-- it under the terms of the GNU General Public License as published by
-- the Free Software Foundation, either version 3 of the License, or
-- any later version.
-- 
-- This program is distributed in the hope that it will be useful,
-- but WITHOUT ANY WARRANTY; without even the implied warranty of
-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-- GNU General Public License for more details.
-- 
-- You should have received a copy of the GNU General Public License
-- along with this program.  If not, see <http://www.gnu.org/licenses/>.
-- 
{-# LANGUAGE OverloadedStrings #-}
module Anansi.Loom.HTML (loomHTML) where
import qualified Data.Text.Lazy as TL
import Control.Monad (forM_)
import Control.Monad.Writer (tell)
import Anansi.Types
import Anansi.Loom

loomHTML :: Loom
loomHTML = Loom "html" $ mapM_ putBlock where
	putBlock b = case b of
		BlockText text -> tell text
		BlockFile path content -> let
			label = TL.concat ["<b>&#xBB; ", escape path, "</b>"]
			in putContent label content
		BlockDefine name content -> let
			label = TL.concat ["<b>&#xAB;", escape name, "&#xBB;</b>"]
			in putContent label content
	
	putContent label cs = do
		tell "<pre>"
		tell label
		tell "\n"
		forM_ cs $ \c -> case c of
			ContentText _ text -> tell . escape $ TL.append text "\n"
			ContentMacro _ indent name -> tell $ formatMacro indent name
		tell "</pre>"

formatMacro :: TL.Text -> TL.Text -> TL.Text
formatMacro indent name = TL.concat [indent, "<i>&#xAB;", escape name, "&#xBB;</i>\n"]

escape :: TL.Text -> TL.Text
escape = TL.concatMap $ \c -> case c of
	'&' -> "&amp;"
	'<' -> "&lt;"
	'>' -> "&gt;"
	'"' -> "&quot;"
	'\'' -> "&apos;"
	_ -> TL.singleton c