/*
 * ComboGrid component: a ComboBox where the dropdown menu (the
 * "Picker") is a Grid with Rows and Columns expects a listConfig
 * object with a columns property roughly based on the GridPicker from
 * https://www.sencha.com/forum/showthread.php?299909
 *
*/

Ext.define('PVE.form.ComboGrid', {
    extend: 'Ext.form.field.ComboBox',
    alias: ['widget.PVE.form.ComboGrid'],

    // this value is used as default value after load()
    preferredValue: undefined,

    // hack: allow to select empty value
    // seems extjs does not allow that when 'editable == false'
    onKeyUp: function(e, t) {
        var me = this;
        var key = e.getKey();

        if (!me.editable && me.allowBlank && !me.multiSelect &&
	    (key == e.BACKSPACE || key == e.DELETE)) {
	    me.setValue('');
	}

        me.callParent(arguments);
    },

// override ExtJS protected method
    onBindStore: function(store, initial) {
        var me = this,
            picker = me.picker,
            extraKeySpec,
            valueCollectionConfig;

        // We're being bound, not unbound...
        if (store) {
            // If store was created from a 2 dimensional array with generated field names 'field1' and 'field2'
            if (store.autoCreated) {
                me.queryMode = 'local';
                me.valueField = me.displayField = 'field1';
                if (!store.expanded) {
                    me.displayField = 'field2';
                }

                // displayTpl config will need regenerating with the autogenerated displayField name 'field1'
                me.setDisplayTpl(null);
            }
            if (!Ext.isDefined(me.valueField)) {
                me.valueField = me.displayField;
            }

            // Add a byValue index to the store so that we can efficiently look up records by the value field
            // when setValue passes string value(s).
            // The two indices (Ext.util.CollectionKeys) are configured unique: false, so that if duplicate keys
            // are found, they are all returned by the get call.
            // This is so that findByText and findByValue are able to return the *FIRST* matching value. By default,
            // if unique is true, CollectionKey keeps the *last* matching value.
            extraKeySpec = {
                byValue: {
                    rootProperty: 'data',
                    unique: false
                }
            };
            extraKeySpec.byValue.property = me.valueField;
            store.setExtraKeys(extraKeySpec);

            if (me.displayField === me.valueField) {
                store.byText = store.byValue;
            } else {
                extraKeySpec.byText = {
                    rootProperty: 'data',
                    unique: false
                };
                extraKeySpec.byText.property = me.displayField;
                store.setExtraKeys(extraKeySpec);
            }

            // We hold a collection of the values which have been selected, keyed by this field's valueField.
            // This collection also functions as the selected items collection for the BoundList's selection model
            valueCollectionConfig = {
                rootProperty: 'data',
                extraKeys: {
                    byInternalId: {
                        property: 'internalId'
                    },
                    byValue: {
                        property: me.valueField,
                        rootProperty: 'data'
                    }
                },
                // Whenever this collection is changed by anyone, whether by this field adding to it,
                // or the BoundList operating, we must refresh our value.
                listeners: {
                    beginupdate: me.onValueCollectionBeginUpdate,
                    endupdate: me.onValueCollectionEndUpdate,
                    scope: me
                }
            };

            // This becomes our collection of selected records for the Field.
            me.valueCollection = new Ext.util.Collection(valueCollectionConfig);

            // We use the selected Collection as our value collection and the basis
            // for rendering the tag list.

            //pve override: since the picker is represented by a grid panel,
            // we changed here the selection to RowModel
            me.pickerSelectionModel = new Ext.selection.RowModel({
                mode: me.multiSelect ? 'SIMPLE' : 'SINGLE',
                // There are situations when a row is selected on mousedown but then the mouse is dragged to another row
                // and released.  In these situations, the event target for the click event won't be the row where the mouse
                // was released but the boundview.  The view will then determine that it should fire a container click, and
                // the DataViewModel will then deselect all prior selections. Setting `deselectOnContainerClick` here will
                // prevent the model from deselecting.
                deselectOnContainerClick: false,
                enableInitialSelection: false,
                pruneRemoved: false,
                selected: me.valueCollection,
                store: store,
                listeners: {
                    scope: me,
                    lastselectedchanged: me.updateBindSelection
                }
            });

            if (!initial) {
                me.resetToDefault();
            }

            if (picker) {
                picker.setSelectionModel(me.pickerSelectionModel);
                if (picker.getStore() !== store) {
                    picker.bindStore(store);
                }
            }
        }
    },

    // copied from ComboBox
    createPicker: function() {
        var me = this;
        var picker;

        var pickerCfg = Ext.apply({
                // pve overrides: display a grid for selection
                xtype: 'gridpanel',
                id: me.pickerId,
                pickerField: me,
                floating: true,
                hidden: true,
                store: me.store,
                displayField: me.displayField,
                preserveScrollOnRefresh: true,
                pageSize: me.pageSize,
                tpl: me.tpl,
                selModel: me.pickerSelectionModel,
                focusOnToFront: false
            }, me.listConfig, me.defaultListConfig);

        picker = me.picker || Ext.widget(pickerCfg);

        if (picker.getStore() !== me.store) {
            picker.bindStore(store);
        }

        if (me.pageSize) {
            picker.pagingToolbar.on('beforechange', me.onPageChange, me);
        }

        // pve overrides: pass missing method in gridPanel to its view
        picker.refresh = function() {
            picker.getSelectionModel().select(me.valueCollection.getRange());
            picker.getView().refresh();
        };
        picker.getNodeByRecord = function() {
            picker.getView().getNodeByRecord(arguments);
        };

        // We limit the height of the picker to fit in the space above
        // or below this field unless the picker has its own ideas about that.
        if (!picker.initialConfig.maxHeight) {
            picker.on({
                beforeshow: me.onBeforePickerShow,
                scope: me
            });
        }
        picker.getSelectionModel().on({
            beforeselect: me.onBeforeSelect,
            beforedeselect: me.onBeforeDeselect,
            focuschange: me.onFocusChange,
            selectionChange: function (sm, selectedRecords) {
                var me = this;
                if (selectedRecords.length) {
                    me.setValue(selectedRecords);
                    me.fireEvent('select', me, selectedRecords);
                }
            },
            scope: me
        });

	// hack for extjs6
	// when the clicked item is the same as the previously selected,
	// it does not select the item
	// instead we hide the picker
	if (!me.multiSelect) {
	    picker.on('itemclick', function (sm,record) {
		if (picker.getSelection()[0] === record) {
		    picker.hide();
		}
	    });
	}

        picker.getNavigationModel().navigateOnSpace = false;

        return picker;
    },

    initComponent: function() {
	var me = this;

	if (me.initialConfig.editable === undefined) {
	    me.editable = false;
	}

	Ext.apply(me, {
	    queryMode: 'local',
	    matchFieldWidth: false
	});

	Ext.applyIf(me, { value: ''}); // hack: avoid ExtJS validate() bug

	Ext.applyIf(me.listConfig, { width: 400 });

        me.callParent();

        // Create the picker at an early stage, so it is available to store the previous selection
        if (!me.picker) {
            me.createPicker();
        }

	me.mon(me.store, 'beforeload', function() {	 
	    if (!me.isDisabled()) {
		me.setDisabled(true);
		me.enableAfterLoad = true;
	    }
	});

	// hack: autoSelect does not work
	me.mon(me.store, 'load', function(store, r, success, o) {
	    if (success) {
		me.clearInvalid();
		
		if (me.enableAfterLoad) {
		    delete me.enableAfterLoad;
		    me.setDisabled(false);
		}

		var def = me.getValue() || me.preferredValue;
		if (def) {
		    me.setValue(def, true); // sync with grid
		}
		var found = false;
		if (def) {
		    if (Ext.isArray(def)) {
			Ext.Array.each(def, function(v) {
			    if (store.findRecord(me.valueField, v)) {
				found = true;
				return false; // break
			    }
			});
		    } else {
			found = store.findRecord(me.valueField, def);
		    }
		}

		if (!found) {
		    var rec = me.store.first();
		    if (me.autoSelect && rec && rec.data) {
			def = rec.data[me.valueField];
			me.setValue(def, true);
		    } else {
			me.setValue(me.editable ? def : '', true);
		    }
		}
	    }
	});
    }
});