/*
Copyright (C) 2007 Google Inc.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

     http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

/*

This sample demonstrates:

  - Use of the content area and content item creation.
  - Using XmlHttpRequest to request a feed.
  - The old, script-based options dialog (deprecated).
*/

view.caption = strings.GADGET_TITLE;
// Set content area flags.
contentArea.contentFlags = gddContentFlagHaveDetails;

// Sets the handler for the options dialog.
// This style options dialog is the old script based method.
// It has been replaced by the "options.xml" dialog.
// See the "ShowOptionsDlg" function.
plugin.onShowOptionsDlg = ShowOptionsDlg; // handler for options dialog

// default/initial settings
options.putDefaultValue("url_0", "http://www.urbandictionary.com/daily.rss");
options.putDefaultValue("url_1", "http://www.wordsmith.org/awad/rss1.xml");
options.putDefaultValue("url_2",
    "http://dictionary.reference.com/wordoftheday/wotd.rss");

setInterval(OnTimer, 1000 * 3600);  // check once every hour
OnTimer();    // update with first set of items

function GetUrls() {
  var arr = new Array();
  var url = " ";
  for (var i = 0; url != undefined; ++i) {
    url = options("url_" + i);
    if (url != undefined)
      arr.push(url);
  }
  return arr;
}

function PutUrls(urls) {
  options.removeAll();
  for (var i = 0; i < urls.length; ++i)
    options("url_" + i) = urls[i];
}

function OnTimer() {
  // issue requests for all our URLs
  var urls = GetUrls();
  for (var i = 0; i < urls.length; ++i) {
    var item = new WordItem(urls[i]);
    item = null;
  }
}

function TrimString(str) {
  str = str.replace( /^\s+/g, "" );   // strip leading whitespaces
  return str.replace( /\s+$/g, "" );  // strip trailing whitespaces
}

function GetDomainName(url) {
  var i;
  if ((i = url.indexOf("//")) != -1)
    url = url.substring(i + 2);
  if ((i = url.indexOf("/")) != -1)
    url = url.substring(0, i);
  var firstDot = url.indexOf(".");
  var secondDot = url.indexOf(".", firstDot + 1);
  while ((i = url.indexOf(".", secondDot + 1)) != -1) {
    firstDot = secondDot;
    secondDot = i;
  }
  if (firstDot != -1 && secondDot != -1) {
    return url.substring(firstDot + 1);
  }
}

//---- Functions to manage the options dialog
function ShowOptionsDlg(wnd) {
  // A label control.
  wnd.AddControl(gddWndCtrlClassLabel, 0, "", strings.strOptionsDlgLabel1Text,
                 10, 10, 380, 25);
  // Edit box.
  wnd.AddControl(gddWndCtrlClassEdit, 0, "url_edit", "", 10, 35, 300, 25);
  // List box.
  wnd.AddControl(gddWndCtrlClassList, 0, "url_list", GetUrls(),
                 10, 70, 300, 100);

  // Add/Remove buttons.
  var add_btn = wnd.AddControl(gddWndCtrlClassButton, 0, "",
    strings.strOptionsDlgAddButtonText, 320, 35, 70, 25);
  var remove_btn = wnd.AddControl(gddWndCtrlClassButton, 0, "",
    strings.strOptionsDlgRemoveButtonText, 320, 70, 70, 25);

  // Set handlers.
  wnd.onClose = OptionsDlgClosed;
  add_btn.onClicked = AddButtonClicked;
  remove_btn.onClicked = RemoveButtonClicked;
}

function AddButtonClicked(wnd, ctrl) {
  var edit = wnd.GetControl("url_edit");
  var url = TrimString(edit.value);
  if (url != "") {
    if (url.substring(0, 7) != "http://")
      url = "http://" + url;
    var list = wnd.GetControl("url_list");
    var urls = new VBArray(list.text).toArray();
    urls.push(url);
    list.text = urls;
    edit.value = "";
  }
}

function RemoveButtonClicked(wnd, ctrl) {
  var list = wnd.GetControl("url_list");
  var url_to_remove = list.value;
  var urls = new VBArray(list.text).toArray();
  for (var i = 0; i < urls.length; ++i) {
    if (urls[i] == url_to_remove) {
      urls.splice(i, 1);
      break;
    }
  }
  list.text = urls;
  if (i < urls.length)
    list.value = urls[i];  // select next one in list
}

function OptionsDlgClosed(wnd, code) {
  if (code == gddIdOK) {
    var list = wnd.GetControl("url_list");
    var urls;
    if (list.text == null)
      urls = new Array();
    else
      urls = new VBArray(list.text).toArray();
    PutUrls(urls);
    contentArea.removeAllContentItems(); // since some may have been deleted
    OnTimer();  // to refresh items and add again
  }
}

//---- A class to manage the requests and callbacks of an item
function WordItem(url) {
  // send request to webserver for data
  var source = GetDomainName(url);
  var http = new XMLHttpRequest();
  http.onreadystatechange = OnData;
  http.open("GET", url, true);
  http.send();

  function OnData() {
    if (http.readyState == 4) { // completed?
      // parse the xml data received
      var doc = new DOMDocument();
      doc.resolveExternals = false;
      doc.validateOnParse = false;
      doc.setProperty('ProhibitDTD', false); 

      doc.loadXML(http.responseText);

      // read the word title, description and link from the xml
      var title, desc, link;
      var elem = doc.getElementsByTagName("item");
      if (elem != null && elem.length > 0) {
        for (var node = elem[0].firstChild;
             node != null;
             node = node.nextSibling) {
          if (node.nodeName == "title")
            title = node.firstChild.nodeValue;
          if (node.nodeName == "description")
            desc = node.firstChild.nodeValue;
          if (node.nodeName == "link")
            link = node.firstChild.nodeValue;
        }
        desc = desc.replace(/<([^>]|\n)*>/g,'');  // remove html tags if present
        desc = desc.replace(/&nbsp;/g, ' ');
        desc = desc.replace(/&quot;/g, '"');
        desc = desc.replace(/&amp;/g, '&');

        var i;
        if ((i = title.indexOf(":")) != -1)
          title = title.substring(0, i);
        if ((i = desc.indexOf(":")) != -1) {
          var phrase = desc.substring(0, i);
          if (phrase == title) {
            desc = desc.substring(i + 1);
          }
        }
      }

      if (title != null) {  // successfully parsed?
        // get the currently shown items and check if our word is in there.
        // If so just update it with the new definition,
        // if not add to the beginning.
        var vbarrItems = contentArea.contentItems;
        if (vbarrItems != null) {
          var items = vbarrItems.toArray();
          for (var i = 0; i < items.length; i++) {
            if (items[i].source == source)
              break;
          }

          var curItem = null;
          if (i == items.length) {
            // Creating new ContentItem.
            curItem = new ContentItem();  // not found so add it fresh
            curItem.source = source;
            curItem.layout = gddContentItemLayoutNews;
            curItem.onDetailsView = OnDetailsView;
            contentArea.addContentItem(curItem, gddItemDisplayInSidebar);
          } else {
            curItem = items[i]; // update the existing item
          }
          // update item's data with latest
          str = title + ":\n" + desc;
          curItem.heading = str;
          curItem.snippet = str;     // to show in details view
          curItem.open_command = link;
        }
      }
      http = null;  // free the http object
    }
  }
}

function OnDetailsView(item) {
  var obj = new Object();
  obj.title = item.heading.substring(0, (item.heading.indexOf(":")));
  // other properties we can set in this object are 'cancel',
  // 'details_control' and 'flags'.
  return obj;
}