_ff-addon-snippet-FindAndSelectAllNonFindBar - wip i dont understand the state listener stuff

gistfile1.txt

var doc = gBrowser.contentDocument;
var ctrler = _getSelectionController(doc.defaultView);

var searchRange = doc.createRange();
searchRange.selectNodeContents(doc.documentElement);

let startPt = searchRange.cloneRange();
startPt.collapse(true);

let endPt = searchRange.cloneRange();
endPt.collapse(false);

let retRange = null;


let finder = Cc["@mozilla.org/embedcomp/rangefind;1"].createInstance().QueryInterface(Ci.nsIFind);
finder.caseSensitive = false;
var i = 0;
while (retRange = finder.Find('the', searchRange, startPt, endPt)) {
    i++;
    var stCont = retRange.startContainer;
    var endCont = retRange.endContainer;
    
    console.log('retRange(' + i + ') = ', retRange);
    console.log('var txt = retRange.commonAncestorContainer.data',retRange.commonAncestorContainer.data);
    
    //now test if one posiion before startOffset and one position after endOffset are WORD characters
    
    var isOneCharBeforeStCharWordChar; //var that holds if the character before the start character is a word character
    if (retRange.startOffset == 0) {
        //no characters befor this characte so obviously not a word char
        isOneCharBeforeStCharWordChar = false;
    } else {
        var oneCharBeforeStChar = stCont.data.substr(retRange.startOffset-1,1);
        if (/\w/.test(oneCharBeforeStChar)) {
            isOneCharBeforeStCharWordChar = true;
        } else {
            isOneCharBeforeStCharWordChar = false;
        }
        console.log('oneCharBeforeStChar',oneCharBeforeStChar);
    }
    
    var isOneCharAfterEndCharWordChar; //var that holds if the character before the start character is a word character
    if (retRange.endOffset == endCont.length - 1) {
        //no characters after this characte so obviously not a word char
        isOneCharAfterEndCharWordChar = false;
    } else {
        var oneCharAferEndChar = endCont.data.substr(retRange.endOffset,1); //no need to subtract 1 from endOffset, it takes into account substr 2nd arg is length and is treated like length I THINK
        if (/\w/.test(oneCharAferEndChar)) {
            isOneCharAfterEndCharWordChar = true;
        } else {
            isOneCharAfterEndCharWordChar = false;
        }
        console.log('oneCharAferEndChar',oneCharAferEndChar);
    }
    
    if (isOneCharBeforeStCharWordChar == false && isOneCharAfterEndCharWordChar == false) {
        //highlight it as surrounding characters are no word characters
        _highlightRange(retRange, ctrler);
        console.log('highlighted it as it was not surrounded by word charactes');
    } else {
        console.log('NOT hilte it as it was not surrounded by word charactes');
    }
    
    
    //break;
    startPt = retRange.cloneRange();
    startPt.collapse(false);
}

//_highlightRange(searchRange,_getSelectionController(gBrowser.contentWindow))

/********/

function _getEditableNode(aNode) {
    while (aNode) {
      if (aNode instanceof Ci.nsIDOMNSEditableElement)
        return aNode.editor ? aNode : null;

      aNode = aNode.parentNode;
    }
    return null;
  }

var _editors;
var _stateListeners;

function _highlightRange(aRange, aController) {
    let node = aRange.startContainer;
    let controller = aController;

    let editableNode = _getEditableNode(node);
    if (editableNode)
      controller = editableNode.editor.selectionController;

    let findSelection = controller.getSelection(128); //i used random instead of //(Ci.nsISelectionController.SELECTION_FIND);
    findSelection.addRange(aRange);
    //i dont understand stateListener stuff
    /*
    if (editableNode) {
      // Highlighting added, so cache this editor, and hook up listeners
      // to ensure we deal properly with edits within the highlighting
      if (!_editors) {
        _editors = [];
        _stateListeners = [];
      }

      let existingIndex = _editors.indexOf(editableNode.editor);
      if (existingIndex == -1) {
        let x = _editors.length;
        _editors[x] = editableNode.editor;
        _stateListeners[x] = _createStateListener();
        _editors[x].addEditActionListener(this);
        _editors[x].addDocumentStateListener(_stateListeners[x]);
      }
    }
    */
  }

  function _getSelectionController(aWindow) {
    // display: none iframes don't have a selection controller, see bug 493658
    if (!aWindow.innerWidth || !aWindow.innerHeight)
      return null;

    // Yuck. See bug 138068.
    let docShell = aWindow.QueryInterface(Ci.nsIInterfaceRequestor)
                          .getInterface(Ci.nsIWebNavigation)
                          .QueryInterface(Ci.nsIDocShell);

    let controller = docShell.QueryInterface(Ci.nsIInterfaceRequestor)
                             .getInterface(Ci.nsISelectionDisplay)
                             .QueryInterface(Ci.nsISelectionController);
    return controller;
  }

  function _createStateListener() {
    return {
      findbar: this,

      QueryInterface: function(aIID) {
        if (aIID.equals(Ci.nsIDocumentStateListener) ||
            aIID.equals(Ci.nsISupports))
          return this;

        throw Components.results.NS_ERROR_NO_INTERFACE;
      },

      NotifyDocumentWillBeDestroyed: function() {
        this.findbar._onEditorDestruction(this);
      },

      // Unimplemented
      notifyDocumentCreated: function() {},
      notifyDocumentStateChanged: function(aDirty) {}
    };
  }
//http://mxr.mozilla.org/mozilla-release/source/toolkit/modules/Finder.jsm?raw=1
  

http://mxr.mozilla.org/mozilla-release/source/content/base/public/nsISelectionController.idl#30

its all about nsISelectionController and nsISelectionDisplay i dont understand that and state listener