// ==UserScript==
// @name           NicoVideo-Pixiv CrossPedia
// @namespace      http://d.hatena.ne.jp/shibason/
// @description    ニコニコ大百科⇔ピクペディアの相互参照
// @include        http://www.nicovideo.jp/watch/*
// @include        http://dic.nicovideo.jp/a/*
// @include        http://www.pixiv.net/member_illust.php*
// @include        http://dic.pixiv.net/a/*
// @author         shibason
// @version        1.0
// ==/UserScript==

(function() {
  var BasePedia = function() {};
  BasePedia.prototype.getIcon = function(keyword, callback) {
    var self = this;
    GM_xmlhttpRequest({
      method: this.method,
      url: this.getCheckURL(keyword),
      onload: function(res) {
        callback(self.createIcon(keyword, self.isExist(res)));
      }
    });
  };
  BasePedia.prototype.createIcon = function(keyword, isExist) {
    var a = document.createElement('a');
    a.setAttribute('target', '_blank');
    a.setAttribute('href', this.getPageURL(keyword));
    var img = document.createElement('img');
    if (isExist) {
      a.setAttribute('title', this.getOnTitle(keyword));
      img.setAttribute('src', this.onImageURL);
    } else {
      a.setAttribute('title', this.getOffTitle(keyword));
      img.setAttribute('src', this.offImageURL);
    }
    a.appendChild(img);
    return a;
  };

  var NicoPedia = function() {
    this.method = 'GET';
    this.onImageURL = 'http://res.nimg.jp/img/common/icon/dic_on.gif';
    this.offImageURL = 'http://res.nimg.jp/img/common/icon/dic_off.gif';
  };
  NicoPedia.prototype = new BasePedia();
  NicoPedia.prototype.getPageURL = function(keyword) {
    return 'http://dic.nicovideo.jp/a/' + encodeURIComponent(keyword);
  };
  NicoPedia.prototype.getCheckURL = function(keyword) {
    keyword = encodeURIComponent(keyword);
    return 'http://api.nicodic.jp/e/__nicopedia_api_1_e_fn_' +
           keyword.replace(/%/g, '_') + '/' + keyword;
  };
  NicoPedia.prototype.isExist = function(res) {
    return !!res.responseText.match(/\(\[1\]\)/);
  };
  NicoPedia.prototype.getOnTitle = function(keyword) {
    return 'ニコニコ大百科 ' + keyword + ' の記事を読む';
  };
  NicoPedia.prototype.getOffTitle = function(keyword) {
    return 'ニコニコ大百科 ' + keyword + ' の記事を書く';
  };

  var PixPedia = function() {
    this.method = 'HEAD';
    this.onImageURL = 'http://source.pixiv.net/source/images/pedia_on.gif';
    this.offImageURL = 'http://source.pixiv.net/source/images/pedia_off.gif';
  };
  PixPedia.prototype = new BasePedia();
  PixPedia.prototype.getPageURL = function(keyword) {
    return 'http://dic.pixiv.net/a/' + encodeURIComponent(keyword);
  };
  PixPedia.prototype.getCheckURL = PixPedia.prototype.getPageURL;
  PixPedia.prototype.isExist = function(res) {
    return !res.responseText;
  };
  PixPedia.prototype.getOnTitle = function(keyword) {
    return 'ピクペディア ' + keyword + ' の記事を読む';
  };
  PixPedia.prototype.getOffTitle = function(keyword) {
    return 'ピクペディア ' + keyword + ' の記事を書く';
  };

  var BaseProcessor = function() {};
  BaseProcessor.prototype.process = function() {
    this.pedia = new this.pediaClass();
    var elements = document.querySelectorAll(this.query);
    for (var i = 0; i < elements.length; i++) {
      this.addIcon(elements[i]);
    }
  };
  BaseProcessor.prototype.addIcon = function(element) {
    var self = this;
    this.pedia.getIcon(element.textContent, function(icon) {
      self.insertIcon(element, icon);
    });
  };

  var NicoVideoProcessor = function() {
    this.pediaClass = PixPedia;
    this.query = 'div#video_tags a.nicopedia';
  };
  NicoVideoProcessor.prototype = new BaseProcessor();
  NicoVideoProcessor.prototype.insertIcon = function(element, icon) {
    icon.firstChild.style.verticalAlign = 'middle';
    if (element.nextSibling && element.nextSibling.tagName == 'A') {
      element = element.nextSibling;
    }
    element.parentNode.insertBefore(icon, element.nextSibling);
  };

  var NicoPediaProcessor = function() {
    this.pediaClass = PixPedia;
    this.query = 'div#main div#article-tab-nico div.article-tab-nico h1';
  }
  NicoPediaProcessor.prototype = new BaseProcessor();
  NicoPediaProcessor.prototype.insertIcon = function(element, icon) {
    icon.style.marginLeft = '0.5em';
    icon.firstChild.style.verticalAlign = 'bottom';
    element.appendChild(icon);
  };

  var PixivProcessor = function() {
    this.pediaClass = NicoPedia;
    this.query = 'span#tags a:not([target])';
  }
  PixivProcessor.prototype = new BaseProcessor();
  PixivProcessor.prototype.insertIcon = function(element, icon) {
    icon.firstChild.style.verticalAlign = 'middle';
    do {
      element = element.nextSibling;
    } while (element && element.tagName != 'A');
    element.parentNode.insertBefore(icon, element.nextSibling);
  };

  var PixPediaProcessor = function() {
    this.pediaClass = NicoPedia;
    this.query = 'div#wrapper h1:first-child a span';
  };
  PixPediaProcessor.prototype = new BaseProcessor();
  PixPediaProcessor.prototype.insertIcon = function(element, icon) {
    icon.style.marginLeft = '0.3em';
    element.parentNode.parentNode.appendChild(icon);
  };

  (new ({
    'www.nicovideo.jp': NicoVideoProcessor,
    'dic.nicovideo.jp': NicoPediaProcessor,
    'www.pixiv.net': PixivProcessor,
    'dic.pixiv.net': PixPediaProcessor
  }[location.hostname])()).process();
})();