--
-- This is the initialization function. It gets called every time Rainlendar
-- is started or refreshed. The initialization function must be defined in the
-- skin file.
--
function Shadow4_RSS_Initialize(skin, window)
  Rainlendar_CreateTimer(60 * 60 * 1000, Shadow4_RSS_OnTimer, skin .. "|" .. window)
  Rainlendar_SetEventHandler(Shadow4_RSS_OnPowerResume, 1000, "", skin .. "|" .. window)
  Shadow4_RSS_OnTimer(skin .. "|" .. window)
end

--
-- A callback function for the timer. This gets called every time the timer triggers.
-- Returns true so the timer will go on forever (false would stop the timer).
--
function Shadow4_RSS_OnTimer(userData)
  _, _, skin, window = userData:find("(.*)|(.*)")

    url = Rainlendar_GetVariable(skin, window, "RSS_location")
  Rainlendar_Log("Downloading: " .. url)
  Rainlendar_Download(url, Shadow4_RSS_OnDownload, userData)
  return True
end

-- A callback function which gets called when computer wakes up from sleep.
-- This reloads the RSS feed.
function Shadow4_RSS_OnPowerResume(eventData, userData)
  Shadow4_RSS_OnTimer(userData)
end

--
-- A callback function for the downloading. This gets called after the given file
-- has been downloaded from the net. The data is the downloaded file.
-- In this case the rss feed is parsed and the list is filled with the data.
--
function Shadow4_RSS_OnDownload(result, data, userData)
  _, _, skin, window = userData:find("(.*)|(.*)")

  -- Parse the data and fill in the list item data
  if (result == 200) or (result == 0) then
    -- Download succeeded
    local strTitle

    -- Erase the existing items  
    Rainlendar_SetItemValue(window, "RSS.list", "list", "")

    -- Get type of Feed
    _, _, feed_type = data:find("<?xml.->.-<(%a+)")
    Rainlendar_Log("Feed Type: " .. feed_type)
    local tag_entry = ""
    local tag_title = ""
    local tag_link = ""
    local tag_desc = ""
    local tag_author = ""
    local tag_date = ""

    if (feed_type == "rss") then
      tag_entry = "<item.->(.-)</item.->"
      tag_title = "<title>(.-)</title>"
      tag_link = "<link>(.-)</link>"
      tag_desc = "<description>(.-)</description>"
      tag_author = "<author>(.-)</author>"
      tag_date = "<pubDate>(.-)</pubDate>"
    elseif(feed_type == "feed") then
      tag_entry = "<entry.->(.-)</entry.->"
      tag_title = "<title.->(.-)</title>"
      tag_link = "<link rel=\"alternate\".-href=\"(.-)\".-/>"
      tag_link2 = "<link.-href=\"(.-)\".-/>"
      tag_desc = "<summary.->(.-)</summary>"
      tag_author = "<author>.-<name>(.-)</name>.-</author>"
      tag_date = "<updated>(.-)</updated>"
    elseif(feed_type == "rdf") then
      tag_entry = "<item.->(.-)</item.->"
      tag_title = "<title>(.-)</title>"
      tag_link = "<link>(.-)</link>"
      tag_desc = "<description>(.-)</description>"
      tag_author = "<dc:creator>(.-)</dc:creator>"
      tag_date = "<dc:date>(.-)</dc:date>"
    end

    -- Get the first title and set it to the window
    _, _, title = data:find(tag_title)
    if (title) then

      -- Clean the CDATA from the title
      _, _, newTitle = title:find("<!%[CDATA%[(.-)%]%]>")
      if (newTitle) then
        title = newTitle
      end

      title = Shadow4_RSS_DecodeString(title)

      if (title) then    
        Rainlendar_SetItemValue(window, "RSS.title", "text", title)
      else
        Rainlendar_SetItemValue(window, "RSS.title", "text", "RSS")
      end
    end

    -- Find the items and their components
    pos = 1
    for item in string.gfind(data, tag_entry) do
      _, _, title = item:find(tag_title)
      _, _, link = item:find(tag_link)
      _, _, desc = item:find(tag_desc)
      _, _, author = item:find(tag_author)
      _, _, date = item:find(tag_date)

      if (link == nil and tag_link2) then
        _, _, link = item:find(tag_link2)
      end

      if (desc == nil) then
        _, _, desc = item:find("<content.->(.-)</content.->")
      end
      if (desc) then
        _, _, newDesc = desc:find("<!%[CDATA%[(.-)%]%]>")
      end
      if (newDesc) then
        desc = newDesc
      end

      if (title) then
        -- Clean the CDATA from the title
        _, _, newTitle = title:find("<!%[CDATA%[(.-)%]%]>")
        if (newTitle) then
          title = newTitle
        end

        text = ""
        if (date) then
          text = text .. "Date: " .. date .. "\n"
        end

        if (author) then
          text = text .. "Author: " .. author .. "\n"
        end

        if (desc) then
          text = text .. desc
        end

        title = Shadow4_RSS_DecodeString(title)
        text = Shadow4_RSS_DecodeString(text)

        -- Remove html from the text
        text = string.gsub(text, "<.->", "")

        -- Put the parsed data to the list and its tooltip
        Rainlendar_SetItemValue(window, "RSS.list", "list." .. pos .. ".type", "1")
        if (link) then
          link = Shadow4_RSS_DecodeString(link)
          Rainlendar_SetItemValue(window, "RSS.list", "list." .. pos .. ".text", "[[" .. link .. "][" .. title .. "]]")
          Rainlendar_SetItemValue(window, "RSS.list", "list." .. pos .. ".tooltipHeader", "[[" .. link .. "][" .. title .. "]]")
        else
          Rainlendar_SetItemValue(window, "RSS.list", "list." .. pos .. ".text", title)
          Rainlendar_SetItemValue(window, "RSS.list", "list." .. pos .. ".tooltipHeader", title)
        end
        Rainlendar_SetItemValue(window, "RSS.list", "list." .. pos .. ".tooltipText", text)
        pos = pos + 1
      end
    end

    -- Show an error if we were not able to parse anything
    if (pos == 1) then
      Rainlendar_SetItemValue(window, "RSS.title", "text", Rainlendar_GetString("Parsing failed!"))
    end

  else
    -- Download failed
    Rainlendar_SetItemValue(window, "RSS.title", "text", Rainlendar_GetString("Download failed!"))
  end
    Rainlendar_Redraw(1, window)
end

-- Converts the &#NNN; values to utf-8
function Shadow4_RSS_DecodeString(s)
  s = string.gsub(s, "&#(x%x+);", 
    function (x)
      x = x:sub(2)
      val = tonumber(x, 16)
      if (val < 128) then
        return string.char(val)
      elseif (val < 2048) then
        return string.char(192 + val / 64) .. string.char(128 + (val % 64))
      elseif (val < 65536) then
        return string.char(224 + val / 4096) .. string.char(128 + ((val / 64) % 64)) .. string.char(128 + (val % 64))
      end
    end)

  s = string.gsub(s, "&#(%d+);", 
    function (d)
      val = tonumber(d, 10)
      if (val < 128) then
        return string.char(val)
      elseif (val < 2048) then
        return string.char(192 + val / 64) .. string.char(128 + (val % 64))
      elseif (val < 65536) then
        return string.char(224 + val / 4096) .. string.char(128 + ((val / 64) % 64)) .. string.char(128 + (val % 64))
      end
    end)
    
  -- Clean the data
  s = string.gsub(s, "&(.-);", 
    function (str)
      str = str:lower()
      if (str == "\r") then return ""
      elseif (str == "quot") then return "\""
      elseif (str == "amp") then return "&"
      elseif (str == "lt") then return "<"
      elseif (str == "gt") then return ">"

      elseif (str == "nbsp") then return " "
      elseif (str == "iexcl") then return "¡"
      elseif (str == "cent") then return "¢"
      elseif (str == "pound") then return "£"
      elseif (str == "curren") then return "¤"
      elseif (str == "yen") then return "¥"
      elseif (str == "brvbar") then return "¦"
      elseif (str == "sect") then return "§"
      elseif (str == "uml") then return "¨"
      elseif (str == "copy") then return "©"
      elseif (str == "ordf") then return "ª"
      elseif (str == "laquo") then return "«"
      elseif (str == "not") then return "¬"
      elseif (str == "shy") then return "­"
      elseif (str == "reg") then return "®"
      elseif (str == "macr") then return "¯"
      elseif (str == "deg") then return "°"
      elseif (str == "plusmn") then return "±"
      elseif (str == "sup2") then return "²"
      elseif (str == "sup3") then return "³"
      elseif (str == "acute") then return "´"
      elseif (str == "micro") then return "µ"
      elseif (str == "para") then return "¶"
      elseif (str == "middot") then return "·"
      elseif (str == "cedil") then return "¸"
      elseif (str == "sup1") then return "¹"
      elseif (str == "ordm") then return "º"
      elseif (str == "raquo") then return "»"
      elseif (str == "frac14") then return "¼"
      elseif (str == "frac12") then return "½"
      elseif (str == "frac34") then return "¾"
      elseif (str == "iquest") then return "¿"
      elseif (str == "times") then return "×"
      elseif (str == "divide") then return "÷"
      elseif (str == "Agrave") then return "À"
      elseif (str == "Aacute") then return "Á"
      elseif (str == "Acirc") then return "Â"
      elseif (str == "Atilde") then return "Ã"
      elseif (str == "Auml") then return "Ä"
      elseif (str == "Aring") then return "Å"
      elseif (str == "AElig") then return "Æ"
      elseif (str == "Ccedil") then return "Ç"
      elseif (str == "Egrave") then return "È"
      elseif (str == "Eacute") then return "É"
      elseif (str == "Ecirc") then return "Ê"
      elseif (str == "Euml") then return "Ë"
      elseif (str == "Igrave") then return "Ì"
      elseif (str == "Iacute") then return "Í"
      elseif (str == "Icirc") then return "Î"
      elseif (str == "Iuml") then return "Ï"
      elseif (str == "ETH") then return "Ð"
      elseif (str == "Ntilde") then return "Ñ"
      elseif (str == "Ograve") then return "Ò"
      elseif (str == "Oacute") then return "Ó"
      elseif (str == "Ocirc") then return "Ô"
      elseif (str == "Otilde") then return "Õ"
      elseif (str == "Ouml") then return "Ö"
      elseif (str == "Oslash") then return "Ø"
      elseif (str == "Ugrave") then return "Ù"
      elseif (str == "Uacute") then return "Ú"
      elseif (str == "Ucirc") then return "Û"
      elseif (str == "Uuml") then return "Ü"
      elseif (str == "Yacute") then return "Ý"
      elseif (str == "THORN") then return "Þ"
      elseif (str == "szlig") then return "ß"
      elseif (str == "agrave") then return "à"
      elseif (str == "aacute") then return "á"
      elseif (str == "acirc") then return "â"
      elseif (str == "atilde") then return "ã"
      elseif (str == "auml") then return "ä"
      elseif (str == "aring") then return "å"
      elseif (str == "aelig") then return "æ"
      elseif (str == "ccedil") then return "ç"
      elseif (str == "egrave") then return "è"
      elseif (str == "eacute") then return "é"
      elseif (str == "ecirc") then return "ê"
      elseif (str == "euml") then return "ë"
      elseif (str == "igrave") then return "ì"
      elseif (str == "iacute") then return "í"
      elseif (str == "icirc") then return "î"
      elseif (str == "iuml") then return "ï"
      elseif (str == "eth") then return "ð"
      elseif (str == "ntilde") then return "ñ"
      elseif (str == "ograve") then return "ò"
      elseif (str == "oacute") then return "ó"
      elseif (str == "ocirc") then return "ô"
      elseif (str == "otilde") then return "õ"
      elseif (str == "ouml") then return "ö"
      elseif (str == "oslash") then return "ø"
      elseif (str == "ugrave") then return "ù"
      elseif (str == "uacute") then return "ú"
      elseif (str == "ucirc") then return "û"
      elseif (str == "uuml") then return "ü"
      elseif (str == "yacute") then return "ý"
      elseif (str == "thorn") then return "þ"
      elseif (str == "yuml") then return "ÿ"

      else return str
      end
    end)
   
  return s
end