function getChildTagsByType(topTag, tagType)
   local tags = {}
   for key, value in topTag do
      if type(value)=="table" then if valOrNil(value.label) == tagType then tinsert(tags, value) end end
   end
   return tags
end

function parseCorrectType(ParsedXML)
   if ParsedXML[2] == nil then return {title="N/A", link="N/A", description="N/A"}, {n=0, nEnc=0, feedType="Invalid feed"} end

   feedType = ParsedXML[2].label
   if feedType == "rss" then
      rssVersion = ParsedXML[2].args["version"]
      return parseRSS(ParsedXML, rssVersion)
   elseif feedType == "rdf" or string.find(feedType, "[Rr][Dd][Ff][:]?[Rr][Dd][Ff]") then
      return parseRDF(ParsedXML)
   else
      return {title="N/A", link="N/A", description="N/A"}, {n=0, nEnc=0, feedType="Unknown feed type"}
   end
end

function parseRSS(ParsedXML, rssVersion)
   local channel = ParsedXML[2][1]
   local channelInfo = {}
   local feeditems = {}
   channelInfo["title"] = getChildTagsByType(channel, "title")[1][1]
   channelInfo["link"] = getChildTagsByType(channel, "link")[1][1]
   channelInfo["description"] = getChildTagsByType(channel, "description")[1][1]
   local items = getChildTagsByType(channel, "item")
   local parsedFeed = {}
   local n, nEnc = 0, 0
   for key, value in items do
      local title, link, description = getChildTagsByType(value, "title")[1], getChildTagsByType(value, "link")[1], getChildTagsByType(value, "description")[1]
      local enc = getChildTagsByType(value, "enclosure")
      local newItem = {}
      newItem["title"] = title[1]
      newItem["link"] = link[1]
      newItem["description"] = description[1]
      if table.getn(enc) > 0 then
         local enclosures = {}
         for key, val in enc do
            nEnc = nEnc + 1
            enclosures[key] = val.args.url
         end
         newItem.enclosures = enclosures
      end
      tinsert(feeditems, newItem)
      n = n + 1
   end
   parsedFeed["items"] = feeditems
   parsedFeed["n"] = n
   parsedFeed["nEnc"] = nEnc
   parsedFeed["feedType"] = "RSS "..rssVersion
   return channelInfo, parsedFeed
end

function parseRDF(ParsedXML)
   local channel = ParsedXML[2][1]
   local channelInfo = {}
   local feeditems = {}
   channelInfo["title"] = getChildTagsByType(channel, "title")[1][1]
   channelInfo["link"] = getChildTagsByType(channel, "link")[1][1]
   channelInfo["description"] = getChildTagsByType(channel, "description")[1][1]
   local itemsTag = getChildTagsByType(channel, "items")[1]
   local items = getChildTagsByType(ParsedXML[2], "item")
   local parsedFeed = {}
   local n, nEnc = 0, 0
   for key, value in items do
      local title, link, description = getChildTagsByType(value, "title")[1], getChildTagsByType(value, "link")[1], getChildTagsByType(value, "description")[1]
      local enc = getChildTagsByType(value, "enclosure")
      local newItem = {}
      newItem["title"] = title[1]
      newItem["link"] = link[1]
      newItem["description"] = description[1]
      if table.getn(enc) > 0 then
         local enclosures = {}
         for key, val in enc do
            nEnc = nEnc + 1
            enclosures[key] = val.args.url
         end
         newItem.enclosures = enclosures
      end
      tinsert(feeditems, newItem)
      n = n + 1
   end
   parsedFeed["items"] = feeditems
   parsedFeed["n"] = n
   parsedFeed["nEnc"] = nEnc
   parsedFeed["feedType"] = "RDF"
   return channelInfo, parsedFeed
end

function writePlainText(title, ParsedFeed)
   local outfile = assert(io.open("feeds/"..fixFileName(title)..".txt", "w"))
   for key, item in ParsedFeed.items do
      outfile:write("Title: "..item.title.."\r\n")
      outfile:write("Link: "..item.link.."\r\n")
      desc = string.gsub(item.description, '[<][!][[]CDATA[[]',"")
      desc = string.gsub(desc, '[]][]][>]',"")
      outfile:write("Description: "..string.gsub(desc, "<(%/?)([%w:]+)(.-)(%/?)>","").."\r\n")
      if type(item.enclosures) ~= "nil" then
         outfile:write("Enclosures:".."\r\n")
         for key, enclosure in item.enclosures do
            outfile:write(enclosure.."\r\n")
         end
      end
      outfile:write("\r\n")
   end
   outfile:close()
end