{-
	Copyright 2013,2014 Marcelo Millani
	
	This file is part of boomange.

    boomange 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
    (at your option) any later version.

    boomange 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 boomange.  If not, see <http://www.gnu.org/licenses/>
-}
module Data.Builder where

import Data.Tree

import Data.Entities

splitSet _ [] = ([],[])
splitSet f (h:r) =
  let (true,false) = splitSet f r in
  if f h then (h:true,false)
  else (true,h:false)

makeError msg fname = 
  let file = Node{rootLabel = "file://" ++ fname, subForest = []}
      link = Node{rootLabel = fname, subForest = [file]} in
  Node{rootLabel = "Error: " ++ msg, subForest = [link] }

-- | builds the bookmark tree
buildBookmarks fname Node{rootLabel = rl, subForest = sForest} = 
  case sForest of
    [] -> buildBookmarks fname (makeError ("empty tree (" ++ rl ++ ")") fname)
    [Node{rootLabel = l, subForest = []} ] -> Url{name = rl, url = l}
    _ -> Folder{name = rl, children = map (buildBookmarks fname ) sForest}

-- | generates html for the given bookmarks
htmlBookmarks bookmark = concat $ map (htmlBookmarks' 0) bookmark
htmlBookmarks' depth bookmark = 
  case bookmark of
    Folder{name = n, children = c} ->
      ident ++ "<div class='folder'>\n"
      ++ ident ++ "<p class='folder'>" ++ n ++ "</p>\n"
      ++ (concat $ map (htmlBookmarks' (depth+1)) c )
      ++ ident ++ "</div>\n"
    Url{name = n, url = u} ->     
      ident ++ "<a class='url' href='" ++ u ++ "'>" ++ n ++ "</a><br>\n"
  where
    ident = take depth $ repeat '\t'