/* ************************************************************************

   qooxdoo - the new era of web development

   http://qooxdoo.org

   Copyright:
     2006 by STZ-IDA, Germany, http://www.stz-ida.de

   License:
     LGPL 2.1: http://www.gnu.org/licenses/lgpl.html

   Authors:
     * Til Schneider (til132)

************************************************************************ */

/* ************************************************************************

#module(ui_table)

************************************************************************ */

/**
 * Shows the header of a table.
 *
 * @param paneScroller {TablePaneScroller} the TablePaneScroller the header belongs to.
 */
qx.OO.defineClass("qx.ui.table.TablePaneHeader", qx.ui.layout.HorizontalBoxLayout,
function(paneScroller) {
  qx.ui.layout.HorizontalBoxLayout.call(this);

  this._paneScroller = paneScroller;
});


/**
 * Returns the TablePaneScroller this header belongs to.
 *
 * @return {TablePaneScroller} the TablePaneScroller.
 */
qx.Proto.getPaneScroller = function() {
  return this._paneScroller;
};


/**
 * Returns the table this header belongs to.
 *
 * @return {Table} the table.
 */
qx.Proto.getTable = function() {
  return this._paneScroller.getTable();
};


/**
 * Event handler. Called when the width of a column has changed.
 *
 * @param evt {Map} the event.
 */
qx.Proto._onColWidthChanged = function(evt) {
  var data = evt.getData();
  this.setColumnWidth(data.col, data.newWidth);
}


/**
 * Event handler. Called the column order has changed.
 *
 * @param evt {Map} the event.
 */
qx.Proto._onColOrderChanged = function(evt) {
  this._updateContent(true);
}


/**
 * Event handler. Called when the pane model has changed.
 *
 * @param evt {Map} the event.
 */
qx.Proto._onPaneModelChanged = function(evt) {
  this._updateContent(true);
}


/**
 * Event handler. Called when the table model meta data has changed.
 *
 * @param evt {Map} the event.
 */
qx.Proto._onTableModelMetaDataChanged = function(evt) {
  this._updateContent();
}


/**
 * Sets the column width. This overrides the width from the column model.
 *
 * @param col {int} the column to change the width for.
 * @param width {int} the new width.
 */
qx.Proto.setColumnWidth = function(col, width) {
  var x = this.getPaneScroller().getTablePaneModel().getX(col);
  var children = this.getChildren();
  if (children[x] != null) {
    children[x].setWidth(width);
  }
}


/**
 * Sets the column the mouse is currently over.
 *
 * @param col {int} the model index of the column the mouse is currently over or
 *    null if the mouse is over no column.
 */
qx.Proto.setMouseOverColumn = function(col) {
  if (col != this._lastMouseOverColumn) {
    var paneModel = this.getPaneScroller().getTablePaneModel();
    var children = this.getChildren();

    if (this._lastMouseOverColumn != null) {
      var widget = children[paneModel.getX(this._lastMouseOverColumn)];
      if (widget != null) {
        widget.removeState("mouseover");
      }
    }
    if (col != null) {
      children[paneModel.getX(col)].addState("mouseover");
    }

    this._lastMouseOverColumn = col;
  }
}


/**
 * Shows the feedback shown while a column is moved by the user.
 *
 * @param col {int} the model index of the column to show the move feedback for.
 * @param x {int} the x position the left side of the feeback should have
 *    (in pixels, relative to the left side of the header).
 */
qx.Proto.showColumnMoveFeedback = function(col, x) {
  var elem = this.getElement();
  if (this._moveFeedback == null) {
    var xPos = this.getPaneScroller().getTablePaneModel().getX(col);
    var cellWidget = this.getChildren()[xPos];

    // Create the feedback
    // Workaround: Since a cloned widget throws an exception when it is
    //       added to another component we have to create a new one
    //       using the renderer
    //this._moveFeedback = cellWidget.clone();
    var tableModel = this.getTable().getTableModel();
    var columnModel = this.getTable().getTableColumnModel();
    var cellInfo = { xPos:xPos, col:col, name:tableModel.getColumnName(col) }
    var cellRenderer = columnModel.getHeaderCellRenderer(col);
    this._moveFeedback = cellRenderer.createHeaderCell(cellInfo);

    // Configure the feedback
    with (this._moveFeedback) {
      setWidth(cellWidget.getBoxWidth());
      setHeight(cellWidget.getBoxHeight());
      setZIndex(1000000);
      setOpacity(0.8);
      setTop(qx.dom.Location.getClientBoxTop(elem));
    }
    this.getTopLevelWidget().add(this._moveFeedback);
  }

  this._moveFeedback.setLeft(qx.dom.Location.getClientBoxLeft(elem) + x);
}


/**
 * Hides the feedback shown while a column is moved by the user.
 */
qx.Proto.hideColumnMoveFeedback = function() {
  if (this._moveFeedback != null) {
    this.getTopLevelWidget().remove(this._moveFeedback);
    this._moveFeedback.dispose();
    this._moveFeedback = null;
  }
}


/**
 * Returns whether the column move feedback is currently shown.
 */
qx.Proto.isShowingColumnMoveFeedback = function() {
  return this._moveFeedback != null;
}


/**
 * Updates the content of the header.
 *
 * @param completeUpdate {boolean} if true a complete update is performed. On a
 *    complete update all header widgets are recreated.
 */
qx.Proto._updateContent = function(completeUpdate) {
  var tableModel = this.getTable().getTableModel();
  var columnModel = this.getTable().getTableColumnModel();
  var paneModel = this.getPaneScroller().getTablePaneModel();

  var children = this.getChildren();
  var oldColCount = children.length;
  var colCount = paneModel.getColumnCount();

  var sortedColum = tableModel.getSortColumnIndex();

  // Remove all widgets on the complete update
  if (completeUpdate) {
    this._cleanUpCells();
  }

  // Update the header
  var cellInfo = {};
  cellInfo.sortedAscending = tableModel.isSortAscending();
  for (var x = 0; x < colCount; x++) {
    var col = paneModel.getColumnAtX(x);

    var colWidth = columnModel.getColumnWidth(col);

    // TODO: Get real cell renderer
    var cellRenderer = columnModel.getHeaderCellRenderer(col);

    cellInfo.xPos = x;
    cellInfo.col = col;
    cellInfo.name = tableModel.getColumnName(col);
    cellInfo.editable = tableModel.isColumnEditable(col);
    cellInfo.sorted = (col == sortedColum);

    // Get the cached widget
    var cachedWidget = children[x];

    // Create or update the widget
    if (cachedWidget == null) {
      // We have no cached widget -> create it
      cachedWidget = cellRenderer.createHeaderCell(cellInfo);
      cachedWidget.set({ width:colWidth, height:"100%" });

      this.add(cachedWidget);
    } else {
      // This widget already created before -> recycle it
      cellRenderer.updateHeaderCell(cellInfo, cachedWidget);
    }
  }
}


/**
 * Cleans up all header cells.
 */
qx.Proto._cleanUpCells = function() {
  var children = this.getChildren();
  for (var x = children.length - 1; x >= 0; x--) {
    var cellWidget = children[x];
    //this.debug("disposed:" + cellWidget.getDisposed() + ",has parent: " + (cellWidget.getParent() != null) + ",x:"+x);
    this.remove(cellWidget);
    cellWidget.dispose();
  }
}


// overridden
qx.Proto.dispose = function() {
  if (this.getDisposed()) {
    return true;
  }

  return qx.ui.layout.HorizontalBoxLayout.prototype.dispose.call(this);
}