/**
 @class YAHOO.ext.grid.EditorSelectionModel
 * Extends {@link YAHOO.ext.grid.DefaultSelectionModel} to enable cell navigation. <br><br> 
 @extends YAHOO.ext.grid.DefaultSelectionModel
 @constructor
 */
YAHOO.ext.grid.EditorSelectionModel = function(){
    YAHOO.ext.grid.EditorSelectionModel.superclass.constructor.call(this);
    /** Number of clicks to activate a cell (for editing) - valid values are 1 or 2
     * @type Number */
    this.clicksToActivateCell = 1;
    this.events['cellactivate'] = new YAHOO.util.CustomEvent('cellactivate');
};

YAHOO.extendX(YAHOO.ext.grid.EditorSelectionModel, YAHOO.ext.grid.DefaultSelectionModel);

YAHOO.ext.grid.EditorSelectionModel.prototype.disableArrowNavigation = false;
YAHOO.ext.grid.EditorSelectionModel.prototype.controlForArrowNavigation = false;

/** @ignore */
YAHOO.ext.grid.EditorSelectionModel.prototype.initEvents = function(){
    this.grid.addListener("cellclick", this.onCellClick, this, true);
    this.grid.addListener("celldblclick", this.onCellDblClick, this, true);
    this.grid.addListener("keydown", this.keyDown, this, true);
};

YAHOO.ext.grid.EditorSelectionModel.prototype.onCellClick = function(grid, rowIndex, colIndex){
    if(this.clicksToActivateCell == 1){
        var row = this.grid.getRow(rowIndex);
        var cell = row.childNodes[colIndex];
        if(cell){
            this.activate(row, cell);
        }
    }
};

YAHOO.ext.grid.EditorSelectionModel.prototype.activate = function(row, cell){
    this.fireEvent('cellactivate', this, row, cell);
    this.grid.doEdit(row, cell);
};

YAHOO.ext.grid.EditorSelectionModel.prototype.onCellDblClick = function(grid, rowIndex, colIndex){
    if(this.clicksToActivateCell == 2){
        var row = this.grid.getRow(rowIndex);
        var cell = row.childNodes[colIndex];
        if(cell){
            this.activate(row, cell);
        }
    }
};

/** @ignore */
YAHOO.ext.grid.EditorSelectionModel.prototype.setRowState = function(row, selected){
    YAHOO.ext.grid.EditorSelectionModel.superclass.setRowState.call(this, row, false, false);
};
/** @ignore */
YAHOO.ext.grid.EditorSelectionModel.prototype.focusRow = function(row, selected){
};

YAHOO.ext.grid.EditorSelectionModel.prototype.getEditorCellAfter = function(cell, spanRows){
    var g = this.grid;
    var next = g.getCellAfter(cell);
    while(next && !g.colModel.isCellEditable(next.columnIndex)){
        next = g.getCellAfter(next);
    }
    if(!next && spanRows){
        var row = g.getRowAfter(g.getRowFromChild(cell));
        if(row){
            next = g.getFirstCell(row);
            if(!g.colModel.isCellEditable(next.columnIndex)){
                next = this.getEditorCellAfter(next);
            }
        }
    }
    return next;
};

YAHOO.ext.grid.EditorSelectionModel.prototype.getEditorCellBefore = function(cell, spanRows){
    var g = this.grid;
    var prev = g.getCellBefore(cell);
    while(prev && !g.colModel.isCellEditable(prev.columnIndex)){
        prev = g.getCellBefore(prev);
    }
    if(!prev && spanRows){
        var row = g.getRowBefore(g.getRowFromChild(cell));
        if(row){
            prev = g.getLastCell(row);
            if(!g.colModel.isCellEditable(prev.columnIndex)){
               prev = this.getEditorCellBefore(prev);
            }
        }
    }
    return prev;
};

YAHOO.ext.grid.EditorSelectionModel.prototype.allowArrowNav = function(e){
    return (!this.disableArrowNavigation && (!this.controlForArrowNavigation || e.ctrlKey));
}
/** @ignore */
YAHOO.ext.grid.EditorSelectionModel.prototype.keyDown = function(e){
    var g = this.grid, cm = g.colModel, cell = g.getEditingCell();
    if(!cell) return;
    var newCell;
    switch(e.browserEvent.keyCode){
         case e.TAB:
             if(e.shiftKey){
                 newCell = this.getEditorCellBefore(cell, true);
             }else{
                 newCell = this.getEditorCellAfter(cell, true);
             }
             e.preventDefault();
         break;
         case e.DOWN:
             if(this.allowArrowNav(e)){
                 var next = g.getRowAfter(g.getRowFromChild(cell));
                 if(next){
                     newCell = next.childNodes[cell.columnIndex];
                 }
             }
         break;
         case e.UP:
             if(this.allowArrowNav(e)){
                 var prev = g.getRowBefore(g.getRowFromChild(cell));
                 if(prev){
                     newCell = prev.childNodes[cell.columnIndex];
                 }
             }
         break;
         case e.RETURN:
             if(e.shiftKey){
                 var prev = g.getRowBefore(g.getRowFromChild(cell));
                 if(prev){
                     newCell = prev.childNodes[cell.columnIndex];
                 }
             }else{
                 var next = g.getRowAfter(g.getRowFromChild(cell));
                 if(next){
                     newCell = next.childNodes[cell.columnIndex];
                 }
             }
         break;
         case e.RIGHT:
             if(this.allowArrowNav(e)){
                 newCell = this.getEditorCellAfter(cell);
             }
         break;
         case e.LEFT:
             if(this.allowArrowNav(e)){
                 newCell = this.getEditorCellBefore(cell);
             }
         break;
    };
    if(newCell){
        this.activate(g.getRowFromChild(newCell), newCell);
        e.stopEvent();
    }
};

/**
 * @class YAHOO.ext.grid.EditorAndSelectionModel
 */
YAHOO.ext.grid.EditorAndSelectionModel = function(){
    YAHOO.ext.grid.EditorAndSelectionModel.superclass.constructor.call(this);
    this.events['cellactivate'] = new YAHOO.util.CustomEvent('cellactivate');
};

YAHOO.extendX(YAHOO.ext.grid.EditorAndSelectionModel, YAHOO.ext.grid.DefaultSelectionModel);

YAHOO.ext.grid.EditorAndSelectionModel.prototype.initEvents = function(){
    YAHOO.ext.grid.EditorAndSelectionModel.superclass.initEvents.call(this);
    this.grid.addListener("celldblclick", this.onCellDblClick, this, true);
};

YAHOO.ext.grid.EditorAndSelectionModel.prototype.onCellDblClick = function(grid, rowIndex, colIndex){
    var row = this.grid.getRow(rowIndex);
    var cell = row.childNodes[colIndex];
    if(cell){
        this.fireEvent('cellactivate', this, row, cell);
        this.grid.doEdit(row, cell);
    }
};