* Copyright 2011 Gaurav Saxena < gsaxena81 AT gmail.com >

*

* 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.

*/

  private FocusPanel fp = new FocusPanel();

  private TextArea ta = new TextArea();

  private JavaScriptObject editor;

  private PopupPanel autoCompletePanel = new PopupPanel();

  public VkEventTextArea() {

    initWidget(fp);

    fp.setSize("100%", "100%");

    DOM.setStyleAttribute(fp.getElement(), "border", "solid 1px gray");

    ScrollPanel scrollPanel = new ScrollPanel();

    autoCompletePanel.add(scrollPanel);

    VerticalPanel optionsHolderPanel = new VerticalPanel();

    scrollPanel.add(optionsHolderPanel);

    DOM.setStyleAttribute(autoCompletePanel.getElement(), "zIndex", Integer.MAX_VALUE + "");

    fp.add(ta);

    fp.addMouseDownHandler(new MouseDownHandler() {

      @Override

      public void onMouseDown(MouseDownEvent event) {

        String id = getRealElementId(Element.as(event.getNativeEvent().getEventTarget()));

        if(!id.isEmpty()) {

          addElementId(id);

          DOM.setCapture(VkEventTextArea.this.getElement());//Using VkDesignerUtil.setCapture / releaseCapture causes IE 9  to have 2 captures and pop up doesn't move

        } else

          DOM.releaseCapture(VkEventTextArea.this.getElement());

        new Timer(){

          @Override

          public void run() {

            focus();

          }}.schedule(1);

      }

    });

    fp.addMouseOutHandler(new MouseOutHandler() {

      @Override

      public void onMouseOut(MouseOutEvent event) {

        if(DOM.getCaptureElement() == null)

          DOM.setCapture(VkEventTextArea.this.getElement());

      }

    });

    fp.addBlurHandler(new BlurHandler() {

      @Override

      public void onBlur(BlurEvent event) {

        DOM.releaseCapture(getElement());

      }

    });

    fp.addKeyDownHandler(new KeyDownHandler(){

      @Override

      public void onKeyDown(KeyDownEvent event) {

        event.stopPropagation();

      }});

  }

  private void showSuggestions(int keyCode) {

    String sentence = getText();

    int startIndex = sentence.length() - 1;

    String elementId = "";

    while(startIndex >= 0 && sentence.charAt(startIndex--) != '.');

    if(startIndex != 0 && startIndex < sentence.length() - 2) {

      String phrase = startIndex == sentence.length() - 1 ? "" : sentence.substring(startIndex + 2);//after the dot is found

      startIndex++;//startIndex points at dot now

      if(startIndex > 0 && sentence.charAt(--startIndex) == ')') {

        char nextChar;

        while(startIndex > 0 && Character.isDigit(nextChar = sentence.charAt(--startIndex)))

          elementId += nextChar;

        if(startIndex > 0 && sentence.charAt(startIndex) == '(')

        {

          if(startIndex > 0 && sentence.charAt(--startIndex) == '&')

            showFunctions(elementId, phrase);

        }

      }

    }

  }

  private native void showFunctions(String elementId, String phrase) /*-{

    var elem = $doc.getElementById(elementId);

    var functions = '';

    var j = 0;

    for(i in elem)

      if(i.toLowerCase().indexOf(phrase.toLowerCase()) == 0 && i.indexOf('_') != 0)

        functions += i + ',';

    var coords = this.@com.vk.gwt.designer.client.designer.VkEventTextArea::editor.cursorCoords(true);

    this.@com.vk.gwt.designer.client.designer.VkEventTextArea::showAutoComplete(Ljava/lang/String;Lcom/google/gwt/dom/client/Element;III)(functions, elem, phrase.length, coords.x, coords.y);

  }-*/;

  private void showAutoComplete(String optionString, final com.google.gwt.dom.client.Element element, final int phraseLength, int x, int y) {

    final String[] options = optionString.split(",");

    ScrollPanel scrollPanel = (ScrollPanel)autoCompletePanel.getWidget();

    VerticalPanel optionHolderPanel = (VerticalPanel)scrollPanel.getWidget();

    optionHolderPanel.clear();

    for (int i = 0, len = options.length; i < len; i++)  {

      final Anchor option = getOption(options[i]);

      final int optionsNum = i;

      optionHolderPanel.add(option);

      option.addClickHandler(new ClickHandler(){

        @Override

        public void onClick(ClickEvent event) {

          setAutoCompleteOption(options[optionsNum], phraseLength, element);

          autoCompletePanel.hide();

        }});

    }

    autoCompletePanel.setAutoHideEnabled(true);

    autoCompletePanel.setPopupPosition(x, y + 10);

    autoCompletePanel.show();

    scrollPanel.setSize("200px",Math.min(optionHolderPanel.getOffsetHeight(), 300) + "px");

  }

  private native void setAutoCompleteOption(String autoCompleteText, int phraseLength, com.google.gwt.dom.client.Element element) /*-{

    var editor = this.@com.vk.gwt.designer.client.designer.VkEventTextArea::editor;

    var cursorPos = editor.getCursor(true);

    var value = element[autoCompleteText];

    if(typeof value == 'function')

      autoCompleteText += '()';

    editor.replaceRange(autoCompleteText, {line: cursorPos.line, ch: cursorPos.ch - phraseLength},

    {line: cursorPos.line, ch: cursorPos.ch});

    editor.focus();

  }-*/;

  private Anchor getOption(String option) {

    final Anchor optionLabel = new Anchor(option);

    optionLabel.setStyleName("eventcode-autocomplete");

    return optionLabel;

  }

  @Override

  public void onLoad() {

    editor = initCodeMirror(ta.getElement());

    DOM.setCapture(getElement());

    new Timer(){

      @Override

      public void run() {

        try{

          focus();

        }catch(Exception e)  {

          schedule(200);

        }

      }

    }.schedule(200);

  }

  private native void addElementId(String id)/*-{

    var editor = this.@com.vk.gwt.designer.client.designer.VkEventTextArea::editor;

    var cursorPos = editor.getCursor(true);

    var stringId = "&(" +  id + ")";

    editor.replaceRange(stringId, {line: cursorPos.line, ch: cursorPos.ch});

    editor.focus();

  }-*/;

  private native JavaScriptObject initCodeMirror(Element textarea)/*-{

    var vkEventTextArea = this;

    return $wnd.CodeMirror.fromTextArea(textarea, {    

       matchBrackets: true,

       mode:  "javascript",

       onKeyEvent: function(editor, keyEvent){

        var keyCode = keyEvent.keyCode;

        if((keyEvent.ctrlKey && keyCode == 32)) {

          vkEventTextArea.@com.vk.gwt.designer.client.designer.VkEventTextArea::showSuggestions(I)(keyCode);

          if(keyEvent.preventDefault)

            keyEvent.preventDefault();

          else

            keyEvent.returnValue = false;

        }

      }

     });

  }-*/;

  public native String getText()/*-{

    return this.@com.vk.gwt.designer.client.designer.VkEventTextArea::editor.getValue().replace(/\s+/g,' ');

  }-*/;

  public void setText(final String text){

    new Timer(){

      @Override

      public void run() {

        try{

          if(editor != null)

            populateJs(editor, text.replaceAll(";", ";\n").replaceAll("\\{","{\n").replaceAll("\\}","}\n").trim());

          else

            schedule(200);

        } catch(Exception e) {

          schedule(200);//editor is not initialized properly

        }

      }

      private native void populateJs(JavaScriptObject editor, String text) /*-{

        editor.replaceRange(text, {line: 0, ch: 0});

        editor.refresh();

      }-*/;

    }.schedule(200);

  }

  private native void setText(JavaScriptObject editor, String text, int lineNum, int charNum) /*-{

    editor.replaceRange(text, {line: lineNum, ch: charNum});

  }-*/;

  private String getRealElementId(com.google.gwt.dom.client.Element element) {

    com.google.gwt.dom.client.Element currentElement = element;

    while(currentElement != null && currentElement.getId().isEmpty())

      currentElement = currentElement.getParentElement();

    if(currentElement != null && currentElement != VkMainDrawingPanel.getInstance().getElement())

      return currentElement.getId();

    else

      return "";

  }

  public void addMouseDownHandler(MouseDownHandler mouseDownHandler) {

    ta.addMouseDownHandler(mouseDownHandler);

  }

  public void setFocus(boolean b) {

    focus();

  }

  private native void focus() /*-{

    this.@com.vk.gwt.designer.client.designer.VkEventTextArea::editor.focus();

  }-*/;