gsnewsbar.js

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function GSnewsBar(barRoot, options) {

  // IE fadein/fadeout is disabled
  // On IE6, when clear type is enabled, you MUST set a background color on
  // the element being tweaked. This is totally impractical. If you dont do this
  // the fonts look terrible/unreadable
  //
  // On IE7, they "fixed" the bug, but they did it by disable font smoothing so
  // once again, the results are terrible. Fix is to just don't do this on IE
  this.br_AgentContains_cache_ = {};
  if (this.br_IsIE()) {
    this.startupDelay = 50;
    this.ieMode = true;
  } else {
    this.startupDelay = 0;
    this.ieMode = false;
  }

  this.CL_RESULTDIV = "resultDiv_gsnb";
  this.CL_RESULTDIV_BOLD = "resultDiv_gsnb resultDivBold_gsnb";
  // FF on win/mac has an interesting issue as well. As soon as opacity hits
  // 100%, the font size seems to change by a pixel or so for many fonts.
  // net result: visible jiggle. The "fix" is to never let ffwin/mac hit 100%...
  this.linkContainerClass = this.CL_RESULTDIV;
  if (this.br_IsNav() && (this.br_IsWin() || this.br_IsMac()) ) {
    if (this.br_IsMac()) {
      this.linkContainerClass = this.CL_RESULTDIV_BOLD;
    }
    this.shortOpacityMode = true;
  } else {
    this.shortOpacityMode = false;
  }

  this.setGlobals();
  this.processArguments(barRoot, options);
  this.adjustGlobals();

  this.buildSuperStructure();
  this.buildSearchControl();

  // build handlers for mousein/mouseout watchers
  // on this.resultsBox
  if ( !this.verticalMode ) {
    this.resultsBox.onmouseover = this.methodClosure(this,
                                            GSnewsBar.prototype.setMouseIn,
                                            [null]);
    this.resultsBox.onmouseout = this.methodClosure(this,
                                            GSnewsBar.prototype.setMouseOut,
                                            [null]);
    if (this.currentResultRoot) {
      this.currentResultRoot.onmouseover = this.methodClosure(this,
                                              GSnewsBar.prototype.setMouseIn,
                                              [null]);
      this.currentResultRoot.onmouseout = this.methodClosure(this,
                                              GSnewsBar.prototype.setMouseOut,
                                              [null]);
    }
  }

  // ie does not like this mode, so defer load on IE
  if (this.ieMode || this.startupDelay != 0) {
    var bootCompleteClosure = this.methodClosure(this,
                                                 GSnewsBar.prototype.bootComplete,
                                                 [null]);
    setTimeout(bootCompleteClosure, this.startupDelay);
  } else {
    this.bootComplete();
  }
}

GSnewsBar.prototype.bootComplete = function() {
  // if we have an auto execute list, then start it up
  if (this.autoExecuteMode) {
    this.cycleTimeClosure = this.methodClosure(this,
                                               GSnewsBar.prototype.cycleTimeout,
                                               [null]);

    // if there is only a single item in the execute list, then
    // disable autoExecuteMode...
    if ( this.executeList.length == 1 ||
         this.cycleTime == GSnewsBar.CYCLE_TIME_MANUAL ) {
      this.switchToListItem(0);
    } else {
      this.cycleTimeout();
    }
  }
}

// cycle time for selecting a news set
GSnewsBar.CYCLE_TIME_EXTRA_SHORT = 3000;
GSnewsBar.CYCLE_TIME_SHORT = 10000;
GSnewsBar.CYCLE_TIME_MEDIUM = 15000;
GSnewsBar.CYCLE_TIME_LONG = 30000;
GSnewsBar.CYCLE_TIME_MANUAL = 3000000;

GSnewsBar.ONE_SECOND = 1000;
GSnewsBar.THREE_SECONDS = 3000;
GSnewsBar.FIVE_SECONDS = 5000;
GSnewsBar.TEN_SECONDS = 10000;

// cycle mode
GSnewsBar.CYCLE_MODE_RANDOM = 1;
GSnewsBar.CYCLE_MODE_LINEAR = 2;

GSnewsBar.MAX_CACHE_LIFETIME = 50;
GSnewsBar.MIN_CACHE_LIFETIME = 1;
GSnewsBar.DEFAULT_CACHE_LIFETIME = 1;
GSnewsBar.MAX_ERROR_COUNT = 1;
GSnewsBar.DEFAULT_QUERY = "Google";
GSnewsBar.MIN_STARTUP_DELAY = 50;
GSnewsBar.MAX_STARTUP_DELAY = 2000;

// result style
GSnewsBar.RESULT_STYLE_EXPANDED = 1;
GSnewsBar.RESULT_STYLE_COMPRESSED = 2;
GSnewsBar.prototype.processArguments = function(barRoot, opt_options) {
  this.totalFailures = 0;
  this.retries = 0;
  this.barRoot = barRoot;
  this.statusRoot = null;
  this.autoExecuteMode = false;
  this.executeList = new Array();
  this.cycleTime = GSnewsBar.CYCLE_TIME_MANUAL;
  this.cycleMode = GSnewsBar.CYCLE_MODE_LINEAR;
  this.cycleNext = 0;
  this.cycleTimer = null;
  this.verticalMode = true;
  this.fadeTimer = null;
  this.mouseInResultArea = false;
  this.mouseOutCallFade = false;
  this.linkTarget = GSearch.LINK_TARGET_SELF;
  this.currentResultRoot = null;
  this.currentResultContainer = null;
  this.cacheLifetime = GSnewsBar.DEFAULT_CACHE_LIFETIME;

  this.fadeIncrement = 10;
  this.fadeTime = 400;
  this.fadeInCallback = GSnewsBar.methodCallback(this,
                                                 GSnewsBar.prototype.fadeIn);
  this.fadeOutCallback = GSnewsBar.methodCallback(this,
                                                  GSnewsBar.prototype.fadeOut);
  this.fadeOpacity = 0;

  // set defaults that are changable via options
  this.resultSetSize = GSearch.SMALL_RESULTSET;
  this.ST_TITLE = "In the news";
  this.resultsBoxClass = this.CL_RESULTSBOX_EXPANDED;
  this.verticalMode = true;

  if (opt_options) {

    // horizontal
    if (opt_options.horizontal && opt_options.horizontal == true ) {
      this.verticalMode = false;
    } else {
      this.verticalMode = true;
    }

    // option.largetResultSet
    if (opt_options.largeResultSet && opt_options.largeResultSet == true ) {
      this.resultSetSize = GSearch.LARGE_RESULTSET;
    } else {
      this.resultSetSize = GSearch.SMALL_RESULTSET;
    }

    // option.resultStyle
    if (opt_options.resultStyle) {
      if (opt_options.resultStyle == GSnewsBar.RESULT_STYLE_EXPANDED) {
        this.resultsBoxClass = this.CL_RESULTSBOX_EXPANDED;
      } else if (opt_options.resultStyle == GSnewsBar.RESULT_STYLE_COMPRESSED) {
        this.resultsBoxClass = this.CL_RESULTSBOX_COMPRESSED;
      }
    }

    if (opt_options.linkTarget) {
      this.linkTarget = opt_options.linkTarget;
    }

    // if currentResult is specified AND we are in horizontal mode,
    // then pick it up.
    if (opt_options.currentResult && !this.verticalMode) {
      this.currentResultRoot = opt_options.currentResult;
      this.removeChildren(this.currentResultRoot);
    }

    if (opt_options.title) {
      this.ST_TITLE = opt_options.title;
    }

    // startupDelay
    if (opt_options.startupDelay &&
        opt_options.startupDelay >= GSnewsBar.MIN_STARTUP_DELAY &&
        opt_options.startupDelay <= GSnewsBar.MAX_STARTUP_DELAY) {
      this.startupDelay = opt_options.startupDelay;
    }

    // cacheLifetime
    if (opt_options.cacheLifetime &&
        opt_options.cacheLifetime >= GSnewsBar.MIN_CACHE_LIFETIME &&
        opt_options.cacheLifetime <= GSnewsBar.MAX_CACHE_LIFETIME ) {
      this.cacheLifetime = opt_options.cacheLifetime;
    }

    // the auto execute list contains
    // a cycleTime value, a cycleMode value, and an array
    // of searchExpressions
    if (opt_options.autoExecuteList) {

      // if specified and valid, then use it, otherwise
      // use default set above
      if (opt_options.autoExecuteList.cycleTime) {
        var cycleTime = opt_options.autoExecuteList.cycleTime;
        if (cycleTime == GSnewsBar.CYCLE_TIME_EXTRA_SHORT ||
            cycleTime == GSnewsBar.CYCLE_TIME_SHORT ||
            cycleTime == GSnewsBar.CYCLE_TIME_MEDIUM ||
            cycleTime == GSnewsBar.CYCLE_TIME_LONG ||
            cycleTime == GSnewsBar.CYCLE_TIME_MANUAL ) {
          this.cycleTime = cycleTime;
        }
      }

      // in vertical mode, cycleTime says how long
      // between new searches. In horizontal mode,
      // it's how long to keep a result up
      if (!this.verticalMode) {
        switch (this.cycleTime) {
        case GSnewsBar.CYCLE_TIME_EXTRA_SHORT:
        case GSnewsBar.CYCLE_TIME_SHORT:
          this.cycleTime = GSnewsBar.THREE_SECONDS;
          break;

        case GSnewsBar.CYCLE_TIME_MEDIUM:
        case GSnewsBar.CYCLE_TIME_MANUAL:
          this.cycleTime = GSnewsBar.FIVE_SECONDS;
          break;

        case GSnewsBar.CYCLE_TIME_LONG:
          this.cycleTime = GSnewsBar.TEN_SECONDS;
          break;
        }
        if (this.ieMode) {
          // since we are not fading in/out, lengthen the cycleTime by 1s
          this.cycleTime += GSnewsBar.ONE_SECOND;
        }
      }

      if (opt_options.autoExecuteList.cycleMode) {
        var cycleMode = opt_options.autoExecuteList.cycleMode;
        if (cycleMode == GSnewsBar.CYCLE_MODE_RANDOM ||
            cycleMode == GSnewsBar.CYCLE_MODE_LINEAR) {
          this.cycleMode = cycleMode;
        }
      }

      // now grab the list...
      if (opt_options.autoExecuteList.executeList &&
          opt_options.autoExecuteList.executeList.length > 0 ) {
        // grab from the list
        for (var i=0; i < opt_options.autoExecuteList.executeList.length; i++) {
          this.executeList.push(
            this.newListItem(opt_options.autoExecuteList.executeList[i]));
        }
        this.autoExecuteMode = true;
        this.currentIndex = 0;
        if (opt_options.autoExecuteList.statusRoot) {
          this.statusRoot = opt_options.autoExecuteList.statusRoot;
        }
      }
    }

    // horizontal mode MUST use autoExecute...
    if (!this.verticalMode && this.autoExecuteMode == false) {
      this.autoExecuteMode = true;
      this.currentIndex = 0;
      this.cycleTime = GSnewsBar.THREE_SECONDS;
      this.executeList.push(this.newListItem(GSnewsBar.DEFAULT_QUERY));
    }
  }

}

GSnewsBar.prototype.testForDefaultQuery = function() {
  if (this.executeList.length == 1 &&
      this.executeList[0].query == GSnewsBar.DEFAULT_QUERY) {
    return true;
  } else {
    return false;
  }
}

GSnewsBar.prototype.resetAutoExecuteListItems = function(newList) {
  if (this.autoExecuteMode && newList.length > 0) {

    // stop the timers...
    this.clearCycleTimer();
    this.clearFadeTimer();

    // clear the status area
    if (this.statusRoot) {
      this.removeChildren(this.statusRoot);
    }

    // nuke the old list
    this.executeList = new Array();

    // build the new list
    for (var i=0; i < newList.length; i++) {
      this.executeList.push(this.newListItem(newList[i]));
    }
    this.currentIndex = 0;

    if (this.statusRoot) {
      this.populateStatusRoot();
    }

    if ( this.executeList.length == 1) {
      this.switchToListItem(0);
    } else {
      this.cycleTimeout();
    }
  }
}

GSnewsBar.prototype.adjustGlobals = function() {
  // horizontal mode changes certain globals...
  // - results are always compressed
  if (this.verticalMode == false) {
    this.resultsBoxClass = this.CL_RESULTSBOX_COMPRESSED;
  }
}

GSnewsBar.prototype.setGlobals = function() {

  // superstructure boxes
  this.CL_NEWSBARBOX = "newsBarBox_gsnb";
  this.CL_NEWSBARBOXFULL = "newsBarBox_gsnb full_gsnb";
  this.CL_NEWSBARBOXEMPTY = "newsBarBox_gsnb empty_gsnb";
  this.CL_NEWSBARINNERBOX = "newsBarInnerBox_gsnb";
  this.CL_VERTICAL = "vertical_gsnb";
  this.CL_HORIZONTAL = "horizontal_gsnb";

  // title
  this.CL_TITLEBOX = "titleBox_gsnb";

  // results
  this.CL_RESULTSBOX_EXPANDED = "resultsBox_gsnb expanded_gsnb";
  this.CL_RESULTSBOX_COMPRESSED = "resultsBox_gsnb compressed_gsnb";
  this.CL_BRANDINGBOX = "brandingBox_gsnb";
  this.CL_SNIPPET = "snippet_gsnb";

  // status