/**
 * A small abstract class that contains the shared behaviour for any summary
 * calculations to be used in the grid.
 * @class Ext.grid.feature.AbstractSummary
 * @extends Ext.grid.feature.Feature
 * @ignore
 */
Ext.define('Ext.grid.feature.AbstractSummary', {
    
    /* Begin Definitions */
   
    extend: 'Ext.grid.feature.Feature',
    
    alias: 'feature.abstractsummary',
   
    /* End Definitions */
   
   /**
    * @cfg {Boolean} showSummaryRow True to show the summary row. Defaults to <tt>true</tt>.
    */
    showSummaryRow: true,
    
    // @private
    nestedIdRe: /\{\{id\}([\w\-]*)\}/g,
    
    /**
     * Toggle whether or not to show the summary row.
     * @param {Boolan} visible True to show the summary row
     */
    toggleSummaryRow: function(visible){
        this.showSummaryRow = !!visible;
    },
    
    /**
     * Gets any fragments to be used in the tpl
     * @private
     * @return {Object} The fragments
     */
    getSummaryFragments: function(){
        var fragments = {};
        if (this.showSummaryRow) {
            Ext.apply(fragments, {
                printSummaryRow: Ext.bind(this.printSummaryRow, this)
            });
        }
        return fragments;
    },
    
    /**
     * Prints a summary row
     * @private
     * @param {Object} index The index in the template
     * @return {String} The value of the summary row
     */
    printSummaryRow: function(index){
        var inner = this.view.getTableChunker().metaRowTpl.join('');
        
        inner = inner.replace('x-grid-row', 'x-grid-row-summary');
        inner = inner.replace('{{id}}', '{gridSummaryValue}');
        inner = inner.replace(this.nestedIdRe, '{id$1}');  
        inner = inner.replace('{[this.embedRowCls()]}', '{rowCls}');
        inner = inner.replace('{[this.embedRowAttr()]}', '{rowAttr}');
        inner = Ext.create('Ext.XTemplate', inner, {
            firstOrLastCls: Ext.view.TableChunker.firstOrLastCls
        });
        
        return inner.applyTemplate({
            columns: this.getPrintData(index)
        });
    },
    
    /**
     * Gets the value for the column from the attached data.
     * @param {Ext.grid.column.Column} column The header
     * @param {Object} data The current data
     * @return {String} The value to be rendered
     */
    getColumnValue: function(column, data){
        var comp = Ext.getCmp(column.id),
            value = data[column.dataIndex],
            renderer = comp.summaryRenderer || comp.renderer;
            
        if (renderer) {
            value = renderer.call(comp.scope || this, value, data, column.dataIndex);
        }
        return value;
    },
    
    /**
     * Get the summary data for a field.
     * @private
     * @param {Ext.data.Store} store The store to get the data from
     * @param {String/Function} type The type of aggregation. If a function is specified it will
     * be passed to the stores aggregate function.
     * @param {String} field The field to aggregate on
     * @param {Boolean} group True to aggregate in grouped mode 
     * @return {Mixed} See the return type for the store functions.
     */
    getSummary: function(store, type, field, group){
        if (type) {
            if (Ext.isFunction(type)) {
                return store.aggregate(type, null, group);
            }
            
            switch (type) {
                case 'count':
                    return store.count(group);
                case 'min':
                    return store.min(field, group);
                case 'max':
                    return store.max(field, group);
                case 'sum':
                    return store.sum(field, group);
                case 'average':
                    return store.average(field, group);
                default:
                    return group ? {} : '';
                    
            }
        }
    }
    
});