/*
This file is part of Ext JS 4.2

Copyright (c) 2011-2013 Sencha Inc

Contact:  http://www.sencha.com/contact

GNU General Public License Usage
This file may be used under the terms of the GNU General Public License version 3.0 as
published by the Free Software Foundation and appearing in the file LICENSE included in the
packaging of this file.

Please review the following information to ensure the GNU General Public License version 3.0
requirements will be met: http://www.gnu.org/copyleft/gpl.html.

If you are unsure which license is appropriate for your use, please contact the sales department
at http://www.sencha.com/contact.

Build date: 2013-05-16 14:36:50 (f9be68accb407158ba2b1be2c226a6ce1f649314)
*/
/**
 * As the number of records increases, the time required for the browser to render them increases. Paging is used to
 * reduce the amount of data exchanged with the client. Note: if there are more records/rows than can be viewed in the
 * available screen area, vertical scrollbars will be added.
 *
 * Paging is typically handled on the server side (see exception below). The client sends parameters to the server side,
 * which the server needs to interpret and then respond with the appropriate data.
 *
 * Ext.toolbar.Paging is a specialized toolbar that is bound to a {@link Ext.data.Store} and provides automatic
 * paging control. This Component {@link Ext.data.Store#method-load load}s blocks of data into the {@link #store} by passing
 * parameters used for paging criteria.
 *
 * {@img Ext.toolbar.Paging/Ext.toolbar.Paging.png Ext.toolbar.Paging component}
 *
 * Paging Toolbar is typically used as one of the Grid's toolbars:
 *
 *     @example
 *     var itemsPerPage = 2;   // set the number of items you want per page
 *
 *     var store = Ext.create('Ext.data.Store', {
 *         id:'simpsonsStore',
 *         autoLoad: false,
 *         fields:['name', 'email', 'phone'],
 *         pageSize: itemsPerPage, // items per page
 *         proxy: {
 *             type: 'ajax',
 *             url: 'pagingstore.js',  // url that will load data with respect to start and limit params
 *             reader: {
 *                 type: 'json',
 *                 root: 'items',
 *                 totalProperty: 'total'
 *             }
 *         }
 *     });
 *
 *     // specify segment of data you want to load using params
 *     store.load({
 *         params:{
 *             start:0,
 *             limit: itemsPerPage
 *         }
 *     });
 *
 *     Ext.create('Ext.grid.Panel', {
 *         title: 'Simpsons',
 *         store: store,
 *         columns: [
 *             { header: 'Name',  dataIndex: 'name' },
 *             { header: 'Email', dataIndex: 'email', flex: 1 },
 *             { header: 'Phone', dataIndex: 'phone' }
 *         ],
 *         width: 400,
 *         height: 125,
 *         dockedItems: [{
 *             xtype: 'pagingtoolbar',
 *             store: store,   // same store GridPanel is using
 *             dock: 'bottom',
 *             displayInfo: true
 *         }],
 *         renderTo: Ext.getBody()
 *     });
 *
 * To use paging, you need to set a pageSize configuration on the Store, and pass the paging requirements to
 * the server when the store is first loaded.
 *
 *     store.load({
 *         params: {
 *             // specify params for the first page load if using paging
 *             start: 0,
 *             limit: myPageSize,
 *             // other params
 *             foo:   'bar'
 *         }
 *     });
 *
 * If using {@link Ext.data.Store#autoLoad store's autoLoad} configuration:
 *
 *     var myStore = Ext.create('Ext.data.Store', {
 *         {@link Ext.data.Store#autoLoad autoLoad}: {start: 0, limit: 25},
 *         ...
 *     });
 *
 * The packet sent back from the server would have this form:
 *
 *     {
 *         "success": true,
 *         "results": 2000,
 *         "rows": [ // ***Note:** this must be an Array
 *             { "id":  1, "name": "Bill", "occupation": "Gardener" },
 *             { "id":  2, "name":  "Ben", "occupation": "Horticulturalist" },
 *             ...
 *             { "id": 25, "name":  "Sue", "occupation": "Botanist" }
 *         ]
 *     }
 *
 * ## Paging with Local Data
 *
 * Paging can also be accomplished with local data using extensions:
 *
 *   - [Ext.ux.data.PagingStore][1]
 *   - Paging Memory Proxy (examples/ux/PagingMemoryProxy.js)
 *
 *    [1]: http://sencha.com/forum/showthread.php?t=71532
 */
Ext.define('Ext.toolbar.Paging', {
    extend: 'Ext.toolbar.Toolbar',
    alias: 'widget.pagingtoolbar',
    alternateClassName: 'Ext.PagingToolbar',
    requires: ['Ext.toolbar.TextItem', 'Ext.form.field.Number'],
    mixins: {
        bindable: 'Ext.util.Bindable'    
    },
    /**
     * @cfg {Ext.data.Store} store (required)
     * The {@link Ext.data.Store} the paging toolbar should use as its data source.
     */

    /**
     * @cfg {Boolean} displayInfo
     * true to display the displayMsg
     */
    displayInfo: false,

    /**
     * @cfg {Boolean} prependButtons
     * true to insert any configured items _before_ the paging buttons.
     */
    prependButtons: false,

    //<locale>
    /**
     * @cfg {String} displayMsg
     * The paging status message to display. Note that this string is
     * formatted using the braced numbers {0}-{2} as tokens that are replaced by the values for start, end and total
     * respectively. These tokens should be preserved when overriding this string if showing those values is desired.
     */
    displayMsg : 'Displaying {0} - {1} of {2}',
    //</locale>

    //<locale>
    /**
     * @cfg {String} emptyMsg
     * The message to display when no records are found.
     */
    emptyMsg : 'No data to display',
    //</locale>

    //<locale>
    /**
     * @cfg {String} beforePageText
     * The text displayed before the input item.
     */
    beforePageText : 'Page',
    //</locale>

    //<locale>
    /**
     * @cfg {String} afterPageText
     * Customizable piece of the default paging text. Note that this string is formatted using
     * {0} as a token that is replaced by the number of total pages. This token should be preserved when overriding this
     * string if showing the total page count is desired.
     */
    afterPageText : 'of {0}',
    //</locale>

    //<locale>
    /**
     * @cfg {String} firstText
     * The quicktip text displayed for the first page button.
     * **Note**: quick tips must be initialized for the quicktip to show.
     */
    firstText : 'First Page',
    //</locale>

    //<locale>
    /**
     * @cfg {String} prevText
     * The quicktip text displayed for the previous page button.
     * **Note**: quick tips must be initialized for the quicktip to show.
     */
    prevText : 'Previous Page',
    //</locale>

    //<locale>
    /**
     * @cfg {String} nextText
     * The quicktip text displayed for the next page button.
     * **Note**: quick tips must be initialized for the quicktip to show.
     */
    nextText : 'Next Page',
    //</locale>

    //<locale>
    /**
     * @cfg {String} lastText
     * The quicktip text displayed for the last page button.
     * **Note**: quick tips must be initialized for the quicktip to show.
     */
    lastText : 'Last Page',
    //</locale>

    //<locale>
    /**
     * @cfg {String} refreshText
     * The quicktip text displayed for the Refresh button.
     * **Note**: quick tips must be initialized for the quicktip to show.
     */
    refreshText : 'Refresh',
    //</locale>

    /**
     * @cfg {Number} inputItemWidth
     * The width in pixels of the input field used to display and change the current page number.
     */
    inputItemWidth : 30,

    /**
     * Gets the standard paging items in the toolbar
     * @private
     */
    getPagingItems: function() {
        var me = this;

        return [{
            itemId: 'first',
            tooltip: me.firstText,
            overflowText: me.firstText,
            iconCls: Ext.baseCSSPrefix + 'tbar-page-first',
            disabled: true,
            handler: me.moveFirst,
            scope: me
        },{
            itemId: 'prev',
            tooltip: me.prevText,
            overflowText: me.prevText,
            iconCls: Ext.baseCSSPrefix + 'tbar-page-prev',
            disabled: true,
            handler: me.movePrevious,
            scope: me
        },
        '-',
        me.beforePageText,
        {
            xtype: 'numberfield',
            itemId: 'inputItem',
            name: 'inputItem',
            cls: Ext.baseCSSPrefix + 'tbar-page-number',
            allowDecimals: false,
            minValue: 1,
            hideTrigger: true,
            enableKeyEvents: true,
            keyNavEnabled: false,
            selectOnFocus: true,
            submitValue: false,
            // mark it as not a field so the form will not catch it when getting fields
            isFormField: false,
            width: me.inputItemWidth,
            margins: '-1 2 3 2',
            listeners: {
                scope: me,
                keydown: me.onPagingKeyDown,
                blur: me.onPagingBlur
            }
        },{
            xtype: 'tbtext',
            itemId: 'afterTextItem',
            text: Ext.String.format(me.afterPageText, 1)
        },
        '-',
        {
            itemId: 'next',
            tooltip: me.nextText,
            overflowText: me.nextText,
            iconCls: Ext.baseCSSPrefix + 'tbar-page-next',
            disabled: true,
            handler: me.moveNext,
            scope: me
        },{
            itemId: 'last',
            tooltip: me.lastText,
            overflowText: me.lastText,
            iconCls: Ext.baseCSSPrefix + 'tbar-page-last',
            disabled: true,
            handler: me.moveLast,
            scope: me
        },
        '-',
        {
            itemId: 'refresh',
            tooltip: me.refreshText,
            overflowText: me.refreshText,
            iconCls: Ext.baseCSSPrefix + 'tbar-loading',
            handler: me.doRefresh,
            scope: me
        }];
    },

    initComponent : function(){
        var me = this,
            pagingItems = me.getPagingItems(),
            userItems   = me.items || me.buttons || [];

        if (me.prependButtons) {
            me.items = userItems.concat(pagingItems);
        } else {
            me.items = pagingItems.concat(userItems);
        }
        delete me.buttons;

        if (me.displayInfo) {
            me.items.push('->');
            me.items.push({xtype: 'tbtext', itemId: 'displayItem'});
        }

        me.callParent();

        me.addEvents(
            /**
             * @event change
             * Fires after the active page has been changed.
             * @param {Ext.toolbar.Paging} this
             * @param {Object} pageData An object that has these properties:
             *
             * - `total` : Number
             *
             *   The total number of records in the dataset as returned by the server
             *
             * - `currentPage` : Number
             *
             *   The current page number
             *
             * - `pageCount` : Number
             *
             *   The total number of pages (calculated from the total number of records in the dataset as returned by the
             *   server and the current {@link Ext.data.Store#pageSize pageSize})
             *
             * - `toRecord` : Number
             *
             *   The starting record index for the current page
             *
             * - `fromRecord` : Number
             *
             *   The ending record index for the current page
             */
            'change',

            /**
             * @event beforechange
             * Fires just before the active page is changed. Return false to prevent the active page from being changed.
             * @param {Ext.toolbar.Paging} this
             * @param {Number} page The page number that will be loaded on change
             */
            'beforechange'
        );
        me.on('beforerender', me.onLoad, me, {single: true});

        me.bindStore(me.store || 'ext-empty-store', true);
    },
    // @private
    updateInfo : function(){
        var me = this,
            displayItem = me.child('#displayItem'),
            store = me.store,
            pageData = me.getPageData(),
            count, msg;

        if (displayItem) {
            count = store.getCount();
            if (count === 0) {
                msg = me.emptyMsg;
            } else {
                msg = Ext.String.format(
                    me.displayMsg,
                    pageData.fromRecord,
                    pageData.toRecord,
                    pageData.total
                );
            }
            displayItem.setText(msg);
        }
    },

    // @private
    onLoad : function(){
        var me = this,
            pageData,
            currPage,
            pageCount,
            afterText,
            count,
            isEmpty,
            item;

        count = me.store.getCount();
        isEmpty = count === 0;
        if (!isEmpty) {
            pageData = me.getPageData();
            currPage = pageData.currentPage;
            pageCount = pageData.pageCount;
            afterText = Ext.String.format(me.afterPageText, isNaN(pageCount) ? 1 : pageCount);
        } else {
            currPage = 0;
            pageCount = 0;
            afterText = Ext.String.format(me.afterPageText, 0);
        }

        Ext.suspendLayouts();
        item = me.child('#afterTextItem');
        if (item) {    
            item.setText(afterText);
        }
        item = me.getInputItem();
        if (item) {
            item.setDisabled(isEmpty).setValue(currPage);
        }
        me.setChildDisabled('#first', currPage === 1 || isEmpty);
        me.setChildDisabled('#prev', currPage === 1 || isEmpty);
        me.setChildDisabled('#next', currPage === pageCount  || isEmpty);
        me.setChildDisabled('#last', currPage === pageCount  || isEmpty);
        me.setChildDisabled('#refresh', false);
        me.updateInfo();
        Ext.resumeLayouts(true);

        if (me.rendered) {
            me.fireEvent('change', me, pageData);
        }
    },
    
    setChildDisabled: function(selector, disabled){
        var item = this.child(selector);
        if (item) {
            item.setDisabled(disabled);
        }
    },

    // @private
    getPageData : function(){
        var store = this.store,
            totalCount = store.getTotalCount();

        return {
            total : totalCount,
            currentPage : store.currentPage,
            pageCount: Math.ceil(totalCount / store.pageSize),
            fromRecord: ((store.currentPage - 1) * store.pageSize) + 1,
            toRecord: Math.min(store.currentPage * store.pageSize, totalCount)

        };
    },

    // @private
    onLoadError : function(){
        if (!this.rendered) {
            return;
        }
        this.setChildDisabled('#refresh', false);
    },
    
    getInputItem: function(){
        return this.child('#inputItem');
    },

    // @private
    readPageFromInput : function(pageData){
        var inputItem = this.getInputItem(),
            pageNum = false,
            v;

        if (inputItem) {
            v = inputItem.getValue();
            pageNum = parseInt(v, 10);
            if (!v || isNaN(pageNum)) {
                inputItem.setValue(pageData.currentPage);
                return false;
            }
        }
        return pageNum;
    },

    onPagingFocus : function(){
        var inputItem = this.getInputItem();
        if (inputItem) {
            inputItem.select();
        }
    },

    // @private
    onPagingBlur : function(e){
        var inputItem = this.getInputItem(),
            curPage;
            
        if (inputItem) {
            curPage = this.getPageData().currentPage;
            inputItem.setValue(curPage);
        }
    },

    // @private
    onPagingKeyDown : function(field, e){
        var me = this,
            k = e.getKey(),
            pageData = me.getPageData(),
            increment = e.shiftKey ? 10 : 1,
            pageNum;

        if (k == e.RETURN) {
            e.stopEvent();
            pageNum = me.readPageFromInput(pageData);
            if (pageNum !== false) {
                pageNum = Math.min(Math.max(1, pageNum), pageData.pageCount);
                if(me.fireEvent('beforechange', me, pageNum) !== false){
                    me.store.loadPage(pageNum);
                }
            }
        } else if (k == e.HOME || k == e.END) {
            e.stopEvent();
            pageNum = k == e.HOME ? 1 : pageData.pageCount;
            field.setValue(pageNum);
        } else if (k == e.UP || k == e.PAGE_UP || k == e.DOWN || k == e.PAGE_DOWN) {
            e.stopEvent();
            pageNum = me.readPageFromInput(pageData);
            if (pageNum) {
                if (k == e.DOWN || k == e.PAGE_DOWN) {
                    increment *= -1;
                }
                pageNum += increment;
                if (pageNum >= 1 && pageNum <= pageData.pageCount) {
                    field.setValue(pageNum);
                }
            }
        }
    },

    // @private
    beforeLoad : function(){
        if (this.rendered) {
            this.setChildDisabled('#refresh', true);
        }
    },

    /**
     * Move to the first page, has the same effect as clicking the 'first' button.
     */
    moveFirst : function(){
        if (this.fireEvent('beforechange', this, 1) !== false){
            this.store.loadPage(1);
        }
    },

    /**
     * Move to the previous page, has the same effect as clicking the 'previous' button.
     */
    movePrevious : function(){
        var me = this,
            prev = me.store.currentPage - 1;

        if (prev > 0) {
            if (me.fireEvent('beforechange', me, prev) !== false) {
                me.store.previousPage();
            }
        }
    },

    /**
     * Move to the next page, has the same effect as clicking the 'next' button.
     */
    moveNext : function(){
        var me = this,
            total = me.getPageData().pageCount,
            next = me.store.currentPage + 1;

        if (next <= total) {
            if (me.fireEvent('beforechange', me, next) !== false) {
                me.store.nextPage();
            }
        }
    },

    /**
     * Move to the last page, has the same effect as clicking the 'last' button.
     */
    moveLast : function(){
        var me = this,
            last = me.getPageData().pageCount;

        if (me.fireEvent('beforechange', me, last) !== false) {
            me.store.loadPage(last);
        }
    },

    /**
     * Refresh the current page, has the same effect as clicking the 'refresh' button.
     */
    doRefresh : function(){
        var me = this,
            current = me.store.currentPage;

        if (me.fireEvent('beforechange', me, current) !== false) {
            me.store.loadPage(current);
        }
    },
    
    getStoreListeners: function() {
        return {
            beforeload: this.beforeLoad,
            load: this.onLoad,
            exception: this.onLoadError
        };
    },

    /**
     * Unbinds the paging toolbar from the specified {@link Ext.data.Store} **(deprecated)**
     * @param {Ext.data.Store} store The data store to unbind
     */
    unbind : function(store){
        this.bindStore(null);
    },

    /**
     * Binds the paging toolbar to the specified {@link Ext.data.Store} **(deprecated)**
     * @param {Ext.data.Store} store The data store to bind
     */
    bind : function(store){
        this.bindStore(store);
    },

    // @private
    onDestroy : function(){
        this.unbind();
        this.callParent();
    }
});
