/*
    Google+ Conditional Fuu => Automatically reply posts on certain conditions.
    Copyright (C) 2012 Jingqin Lynn
    
    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
    (at your option) 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/>.
    
*/

// ==UserScript==
// @name 		Google+ Conditional Fuu
// @namespace		http://project.quietmusic.org/j/
// @description		Automatically reply posts on certain conditions.
// @match		https://plus.google.com/*
// ==/UserScript==

(function() {
  //Use the <base> element to detect Google+ main page.
  var base = document.querySelector('base');
  
  if (!base) return;
  if (!base.href.match(/^https:\/\/plus\.google\.com(\/u\/\d+)?\/?/)) return;
  
  //Chrome V8 don't support unsafeWindow. Time for a hack.
  if (window == unsafeWindow) {
      var span = document.createElement('span');
      span.setAttribute('onclick', 'return window;');
      unsafeWindow =  span.onclick();
  }
  //For shorter code.
  var win = unsafeWindow;
  win.ext = win.ext || {};
  
  if (win.ext.condFuu) {
    return;
  } else {
    win.ext.condFuu = {};
  }
  
  var main = function($) {
    var getLocale = function() {
      var lang = {
        'en': {
          'fuuDefaultValue' : 'Fuu',
          'input_cond_xpath' : 'Please input the XPath expression for the posts to be auto-replyed.',
          'input_reply_value' : 'Please input the text of the reply:'
        },
        'zh-hans': {
          'fuuDefaultValue' : '呼',
          'input_cond_xpath' : '请输入自动回复时，贴子需要满足的条件（XPath 表达式）：',
          'input_reply_value' : '请输入自动回复的文本：'
        },
      };
      //alias for languages
      lang['zh-cn'] = lang['zh-hans'];
      lang['zh-sg'] = lang['zh-hans'];
      lang['zh-tw'] = lang['zh-hant'];
      lang['zh-hk'] = lang['zh-hant'];
      lang['zh'] = lang['zh-hans']; //fallback
      lang[''] = lang['en']; //general fallback
      
      var langCode = localStorage.getItem('cond-fuu-lang') || $.gplus.getLangCode();
      var loc = lang[langCode];
      if(!loc) {
        loc = lang[langCode.substr(0,2)];
        if(!loc) {
          loc = lang[''];
        }
      }
      return loc;
    };

    var fuuOnPost = function (post) {
      var fuuComplete = function() {
        post.stopDynamicSelect(handler);
        $('.ext-fuu-button').attr('data-ext-fuu-ed', 'true');
      };
      var handler = post.dynamicSelect('.g-z-e-Ia-df', function(ed) {
        fuu(ed, post, fuuComplete);
      });
      $.gplus.doClick($('.rBJ4nd', post)[0]);
    };
    
    //Add fuu-text to the editor and then submit the reply.
    var fuu = function (ed, post, callback) {
      if(ed.children.length == 0) {
        var onNodeInserted = function(e) {
          if(!e) e = event;
          ed.removeEventListener('DOMNodeInserted', onNodeInserted, false);
          fuu(ed, post, callback);
        }
        ed.addEventListener('DOMNodeInserted', onNodeInserted, false);
        return;
      }
      if(ed.children[0].tagName == 'DIV') {
        if(callback) callback();
        var handler = $(ed).dynamicSelect('iframe', function (frame) {
          $(ed).stopDynamicSelect(handler);
          //The content in the frame is changing, and DOMNodeInserted won't work.
          //Use setInterval as a workaround.
          var it = setInterval(function() {
            if(frame.contentDocument.body.classList.contains('editable')) {
              clearInterval(it);
              fuu(frame.contentDocument.body, post);
            }
          }, 100);
        });
        return;
      }
      
      if(callback) callback();
      //ed.ownerDocument.body.scrollIntoView(ed);
      ed.textContent = localStorage.getItem('cond-fuu-text') || loc['fuuDefaultValue'];
      
      //"Input" something to enable the submit button.
      $.gplus.doKeypress(ed);
      var submit = $('.b-a-ga', post);
      if(submit.attr('aria-disabled') != 'true') {
        $.gplus.doClick(submit[0]);
      }
      else {
        //Webkit don't support DOMAttrModified.
        //Use setInterval as workaround.
        //Todo: use DOMAttrModified on supported browsers such as Firefox.
        var it = setInterval(function() {
          if(submit.attr('aria-disabled') != 'true') {
            clearInterval(it);
            $.gplus.doClick(submit[0]);
          };
        }, 100);
      }
      return true;
    };
    
    var showSettingUI = function (e) {
      var fuuText = localStorage.getItem('cond-fuu-text') || loc['fuuDefaultValue'];
      localStorage.setItem('cond-fuu-text', prompt(loc['input_reply_value'], fuuText) || fuuText);
      var fuuXPath = localStorage.getItem('cond-fuu-xpath') || 'false()';
      localStorage.setItem('cond-fuu-xpath', prompt(loc['input_cond_xpath'], fuuXPath) || fuuXPath);
      
      localStorage.setItem('cond-fuu-lastPost', new Date());
      
      if (e) e.preventDefault();
    };
    
    //Init
    var loc = getLocale();
    //Match any new posts
    $(document.body).dynamicSelect('.Te', function(post) {
      post = $(post);
      var handler = post.dynamicSelect('.k-Qf-C-RySO6d.UzyZPb', function (postLink) {
        var title = postLink.getAttribute('title');
        if (title != "Timestamp") {
          post.stopDynamicSelect(handler);
          
          var time = new Date(title);
          var lastTime = new Date(localStorage.getItem('cond-fuu-lastPost'));
          
          if (time && time > lastTime && post.xpath(localStorage.getItem('cond-fuu-xpath') || 'false()', 'boolean')) {
            localStorage.setItem('cond-fuu-lastPost', time);
            post.attr('data-ext-cond-fuu', 'matched');
            fuuOnPost(post);
          }
        }
      });
      
    });
    $(document.body).dynamicSelect('.afEYIc', function(button) {
      $(button).on('contextmenu', showSettingUI);
    });
  };
  
  if(win.ext.toolkitReady) {
    main(win.jQuery);
  } else {
    win.ext.toolkitCallback = win.ext.toolkitCallback || [];
    win.ext.toolkitCallback.push(main);
  }
})();