/**
 * @docauthor Robert Dougan <rob@sencha.com>
 *
 * Single checkbox field. Can be used as a direct replacement for traditional checkbox fields. Also serves as a
 * parent class for {@link Ext.form.field.Radio radio buttons}.
 *
 * # Labeling
 *
 * In addition to the {@link Ext.form.Labelable standard field labeling options}, checkboxes
 * may be given an optional {@link #boxLabel} which will be displayed immediately after checkbox. Also see
 * {@link Ext.form.CheckboxGroup} for a convenient method of grouping related checkboxes.
 *
 * # Values
 *
 * The main value of a checkbox is a boolean, indicating whether or not the checkbox is checked.
 * The following values will check the checkbox:
 *
 * - `true`
 * - `'true'`
 * - `'1'`
 * - `'on'`
 *
 * Any other value will uncheck the checkbox.
 *
 * In addition to the main boolean value, you may also specify a separate {@link #inputValue}. This will be
 * sent as the parameter value when the form is {@link Ext.form.Basic#submit submitted}. You will want to set
 * this value if you have multiple checkboxes with the same {@link #name}. If not specified, the value `on`
 * will be used.
 *
 * # Example usage
 *
 *     @example
 *     Ext.create('Ext.form.Panel', {
 *         bodyPadding: 10,
 *         width: 300,
 *         title: 'Pizza Order',
 *         items: [
 *             {
 *                 xtype: 'fieldcontainer',
 *                 fieldLabel: 'Toppings',
 *                 defaultType: 'checkboxfield',
 *                 items: [
 *                     {
 *                         boxLabel  : 'Anchovies',
 *                         name      : 'topping',
 *                         inputValue: '1',
 *                         id        : 'checkbox1'
 *                     }, {
 *                         boxLabel  : 'Artichoke Hearts',
 *                         name      : 'topping',
 *                         inputValue: '2',
 *                         checked   : true,
 *                         id        : 'checkbox2'
 *                     }, {
 *                         boxLabel  : 'Bacon',
 *                         name      : 'topping',
 *                         inputValue: '3',
 *                         id        : 'checkbox3'
 *                     }
 *                 ]
 *             }
 *         ],
 *         bbar: [
 *             {
 *                 text: 'Select Bacon',
 *                 handler: function() {
 *                     Ext.getCmp('checkbox3').setValue(true);
 *                 }
 *             },
 *             '-',
 *             {
 *                 text: 'Select All',
 *                 handler: function() {
 *                     Ext.getCmp('checkbox1').setValue(true);
 *                     Ext.getCmp('checkbox2').setValue(true);
 *                     Ext.getCmp('checkbox3').setValue(true);
 *                 }
 *             },
 *             {
 *                 text: 'Deselect All',
 *                 handler: function() {
 *                     Ext.getCmp('checkbox1').setValue(false);
 *                     Ext.getCmp('checkbox2').setValue(false);
 *                     Ext.getCmp('checkbox3').setValue(false);
 *                 }
 *             }
 *         ],
 *         renderTo: Ext.getBody()
 *     });
 */
Ext.define('Ext.form.field.Checkbox', {
    extend: 'Ext.form.field.Base',
    alias: ['widget.checkboxfield', 'widget.checkbox'],
    alternateClassName: 'Ext.form.Checkbox',
    requires: ['Ext.XTemplate', 'Ext.form.CheckboxManager'],

    // note: {id} here is really {inputId}, but {cmpId} is available
    fieldSubTpl: [
        '<tpl if="boxLabel && boxLabelAlign == \'before\'">',
            '<label id="{cmpId}-boxLabelEl" class="{boxLabelCls} {boxLabelCls}-{boxLabelAlign}" for="{id}">{boxLabel}</label>',
        '</tpl>',
        // Creates not an actual checkbox, but a button which is given aria role="checkbox" and
        // styled with a custom checkbox image. This allows greater control and consistency in
        // styling, and using a button allows it to gain focus and handle keyboard nav properly.
        '<input type="button" id="{id}" ',
            '<tpl if="tabIdx">tabIndex="{tabIdx}" </tpl>',
            'class="{fieldCls} {typeCls}" autocomplete="off" hidefocus="true" />',
        '<tpl if="boxLabel && boxLabelAlign == \'after\'">',
            '<label id="{cmpId}-boxLabelEl" class="{boxLabelCls} {boxLabelCls}-{boxLabelAlign}" for="{id}">{boxLabel}</label>',
        '</tpl>',
        {
            disableFormats: true,
            compiled: true
        }
    ],

    isCheckbox: true,

    /**
     * @cfg {String} [focusCls='x-form-cb-focus']
     * The CSS class to use when the checkbox receives focus
     */
    focusCls: Ext.baseCSSPrefix + 'form-cb-focus',

    /**
     * @cfg {String} [fieldCls='x-form-field']
     * The default CSS class for the checkbox
     */

    /**
     * @cfg {String} [fieldBodyCls='x-form-cb-wrap']
     * An extra CSS class to be applied to the body content element in addition to {@link #fieldBodyCls}.
     * .
     */
    fieldBodyCls: Ext.baseCSSPrefix + 'form-cb-wrap',

    /**
     * @cfg {Boolean} checked
     * true if the checkbox should render initially checked
     */
    checked: false,

    /**
     * @cfg {String} [checkedCls='x-form-cb-checked']
     * The CSS class added to the component's main element when it is in the checked state.
     */
    checkedCls: Ext.baseCSSPrefix + 'form-cb-checked',

    /**
     * @cfg {String} boxLabel
     * An optional text label that will appear next to the checkbox. Whether it appears before or after the checkbox is
     * determined by the {@link #boxLabelAlign} config.
     */

    /**
     * @cfg {String} [boxLabelCls='x-form-cb-label']
     * The CSS class to be applied to the {@link #boxLabel} element
     */
    boxLabelCls: Ext.baseCSSPrefix + 'form-cb-label',

    /**
     * @cfg {String} boxLabelAlign
     * The position relative to the checkbox where the {@link #boxLabel} should appear. Recognized values are 'before'
     * and 'after'.
     */
    boxLabelAlign: 'after',

    /**
     * @cfg {String} inputValue
     * The value that should go into the generated input element's value attribute and should be used as the parameter
     * value when submitting as part of a form.
     */
    inputValue: 'on',

    /**
     * @cfg {String} uncheckedValue
     * If configured, this will be submitted as the checkbox's value during form submit if the checkbox is unchecked. By
     * default this is undefined, which results in nothing being submitted for the checkbox field when the form is
     * submitted (the default behavior of HTML checkboxes).
     */

    /**
     * @cfg {Function} handler
     * A function called when the {@link #checked} value changes (can be used instead of handling the {@link #change
     * change event}).
     * @cfg {Ext.form.field.Checkbox} handler.checkbox The Checkbox being toggled.
     * @cfg {Boolean} handler.checked The new checked state of the checkbox.
     */

    /**
     * @cfg {Object} scope
     * An object to use as the scope ('this' reference) of the {@link #handler} function (defaults to this Checkbox).
     */

    // private overrides
    checkChangeEvents: [],
    inputType: 'checkbox',
    ariaRole: 'checkbox',

    // private
    onRe: /^on$/i,

    initComponent: function(){
        this.callParent(arguments);
        this.getManager().add(this);
    },

    initValue: function() {
        var me = this,
            checked = !!me.checked;

        /**
         * @property {Object} originalValue
         * The original value of the field as configured in the {@link #checked} configuration, or as loaded by the last
         * form load operation if the form's {@link Ext.form.Basic#trackResetOnLoad trackResetOnLoad} setting is `true`.
         */
        me.originalValue = me.lastValue = checked;

        // Set the initial checked state
        me.setValue(checked);
    },

    // private
    onRender : function(ct, position) {
        var me = this;

        /**
         * @property {Ext.Element} boxLabelEl
         * A reference to the label element created for the {@link #boxLabel}. Only present if the component has been
         * rendered and has a boxLabel configured.
         */
        me.addChildEls('boxLabelEl');

        Ext.applyIf(me.subTplData, {
            boxLabel: me.boxLabel,
            boxLabelCls: me.boxLabelCls,
            boxLabelAlign: me.boxLabelAlign
        });

        me.callParent(arguments);
    },

    initEvents: function() {
        var me = this;
        me.callParent();
        me.mon(me.inputEl, 'click', me.onBoxClick, me);
    },

    /**
     * @private Handle click on the checkbox button
     */
    onBoxClick: function(e) {
        var me = this;
        if (!me.disabled && !me.readOnly) {
            this.setValue(!this.checked);
        }
    },

    /**
     * Returns the checked state of the checkbox.
     * @return {Boolean} True if checked, else false
     */
    getRawValue: function() {
        return this.checked;
    },

    /**
     * Returns the checked state of the checkbox.
     * @return {Boolean} True if checked, else false
     */
    getValue: function() {
        return this.checked;
    },

    /**
     * Returns the submit value for the checkbox which can be used when submitting forms.
     * @return {Boolean/Object} True if checked; otherwise either the {@link #uncheckedValue} or null.
     */
    getSubmitValue: function() {
        var unchecked = this.uncheckedValue,
            uncheckedVal = Ext.isDefined(unchecked) ? unchecked : null;
        return this.checked ? this.inputValue : uncheckedVal;
    },

    /**
     * Sets the checked state of the checkbox.
     *
     * @param {Boolean/String/Number} value The following values will check the checkbox:
     * `true, 'true', '1', 1, or 'on'`, as well as a String that matches the {@link #inputValue}.
     * Any other value will uncheck the checkbox.
     * @return {Boolean} the new checked state of the checkbox
     */
    setRawValue: function(value) {
        var me = this,
            inputEl = me.inputEl,
            inputValue = me.inputValue,
            checked = (value === true || value === 'true' || value === '1' || value === 1 ||
                (((Ext.isString(value) || Ext.isNumber(value)) && inputValue) ? value == inputValue : me.onRe.test(value)));

        if (inputEl) {
            inputEl.dom.setAttribute('aria-checked', checked);
            me[checked ? 'addCls' : 'removeCls'](me.checkedCls);
        }

        me.checked = me.rawValue = checked;
        return checked;
    },

    /**
     * Sets the checked state of the checkbox, and invokes change detection.
     * @param {Boolean/String} checked The following values will check the checkbox: `true, 'true', '1', or 'on'`, as
     * well as a String that matches the {@link #inputValue}. Any other value will uncheck the checkbox.
     * @return {Ext.form.field.Checkbox} this
     */
    setValue: function(checked) {
        var me = this;

        // If an array of strings is passed, find all checkboxes in the group with the same name as this
        // one and check all those whose inputValue is in the array, unchecking all the others. This is to
        // facilitate setting values from Ext.form.Basic#setValues, but is not publicly documented as we
        // don't want users depending on this behavior.
        if (Ext.isArray(checked)) {
            me.getManager().getByName(me.name).each(function(cb) {
                cb.setValue(Ext.Array.contains(checked, cb.inputValue));
            });
        } else {
            me.callParent(arguments);
        }

        return me;
    },

    // private
    valueToRaw: function(value) {
        // No extra conversion for checkboxes
        return value;
    },

    /**
     * @private
     * Called when the checkbox's checked state changes. Invokes the {@link #handler} callback
     * function if specified.
     */
    onChange: function(newVal, oldVal) {
        var me = this,
            handler = me.handler;
        if (handler) {
            handler.call(me.scope || me, me, newVal);
        }
        me.callParent(arguments);
    },

    // inherit docs
    beforeDestroy: function(){
        this.callParent();
        this.getManager().removeAtKey(this.id);
    },

    // inherit docs
    getManager: function() {
        return Ext.form.CheckboxManager;
    },

    onEnable: function() {
        var me = this,
            inputEl = me.inputEl;
        me.callParent();
        if (inputEl) {
            // Can still be disabled if the field is readOnly
            inputEl.dom.disabled = me.readOnly;
        }
    },

    setReadOnly: function(readOnly) {
        var me = this,
            inputEl = me.inputEl;
        if (inputEl) {
            // Set the button to disabled when readonly
            inputEl.dom.disabled = readOnly || me.disabled;
        }
        me.readOnly = readOnly;
    },

    // Calculates and returns the natural width of the bodyEl. It's possible that the initial rendering will
    // cause the boxLabel to wrap and give us a bad width, so we must prevent wrapping while measuring.
    getBodyNaturalWidth: function() {
        var me = this,
            bodyEl = me.bodyEl,
            ws = 'white-space',
            width;
        bodyEl.setStyle(ws, 'nowrap');
        width = bodyEl.getWidth();
        bodyEl.setStyle(ws, '');
        return width;
    }

});