<?php

/**
 * @package KantPHP
 * @author  Zhenqiang Zhang <zhenqiang.zhang@hotmail.com>
 * @copyright (c) KantPHP Studio, All rights reserved.
 * @license http://www.opensource.org/licenses/BSD-3-Clause  The BSD 3-Clause License
 */
namespace Kant\Grid;

use Kant\Kant;
use Kant\Helper\Html;
use Kant\Helper\Url;

/**
 * ActionColumn is a column for the [[GridView]] widget that displays buttons for viewing and manipulating the items.
 *
 * To add an ActionColumn to the gridview, add it to the [[GridView::columns|columns]] configuration as follows:
 *
 * ```php
 * 'columns' => [
 * // ...
 * [
 * 'class' => ActionColumn::className(),
 * // you may configure additional properties here
 * ],
 * ]
 * ```
 *
 * For more details and usage information on ActionColumn, see the [guide article on data widgets](guide:output-data-widgets).
 *
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @since 2.0
 */
class ActionColumn extends Column
{

    /**
     * @inheritdoc
     */
    public $headerOptions = [
        'class' => 'action-column'
    ];

    /**
     *
     * @var string the ID of the controller that should handle the actions specified here.
     *      If not set, it will use the currently active controller. This property is mainly used by
     *      [[urlCreator]] to create URLs for different actions. The value of this property will be prefixed
     *      to each action name to form the route of the action.
     */
    public $controller;

    /**
     *
     * @var string the template used for composing each cell in the action column.
     *      Tokens enclosed within curly brackets are treated as controller action IDs (also called *button names*
     *      in the context of action column). They will be replaced by the corresponding button rendering callbacks
     *      specified in [[buttons]]. For example, the token `{view}` will be replaced by the result of
     *      the callback `buttons['view']`. If a callback cannot be found, the token will be replaced with an empty string.
     *     
     *      As an example, to only have the view, and update button you can add the ActionColumn to your GridView columns as follows:
     *     
     *      ```php
     *      ['class' => 'Kant\Grid\ActionColumn', 'template' => '{view} {update}'],
     *      ```
     *     
     * @see buttons
     */
    public $template = '{view} {update} {delete}';

    /**
     *
     * @var array button rendering callbacks. The array keys are the button names (without curly brackets),
     *      and the values are the corresponding button rendering callbacks. The callbacks should use the following
     *      signature:
     *     
     *      ```php
     *      function ($url, $model, $key) {
     *      // return the button HTML code
     *      }
     *      ```
     *     
     *      where `$url` is the URL that the column creates for the button, `$model` is the model object
     *      being rendered for the current row, and `$key` is the key of the model in the data provider array.
     *     
     *      You can add further conditions to the button, for example only display it, when the model is
     *      editable (here assuming you have a status field that indicates that):
     *     
     *      ```php
     *      [
     *      'update' => function ($url, $model, $key) {
     *      return $model->status === 'editable' ? Html::a('Update', $url) : '';
     *      },
     *      ],
     *      ```
     */
    public $buttons = [];

    /**
     *
     * @var array visibility conditions for each button. The array keys are the button names (without curly brackets),
     *      and the values are the boolean true/false or the anonymous function. When the button name is not specified in
     *      this array it will be shown by default.
     *      The callbacks must use the following signature:
     *     
     *      ```php
     *      function ($model, $key, $index) {
     *      return $model->status === 'editable';
     *      }
     *      ```
     *     
     *      Or you can pass a boolean value:
     *     
     *      ```php
     *      [
     *      'update' => \Kant::$app->user->can('update'),
     *      ],
     *      ```
     * @since 2.0.7
     */
    public $visibleButtons = [];

    /**
     *
     * @var callable a callback that creates a button URL using the specified model information.
     *      The signature of the callback should be the same as that of [[createUrl()]]
     *      Since 2.0.10 it can accept additional parameter, which refers to the column instance itself:
     *     
     *      ```php
     *      function (string $action, mixed $model, mixed $key, integer $index, ActionColumn $this) {
     *      //return string;
     *      }
     *      ```
     *     
     *      If this property is not set, button URLs will be created using [[createUrl()]].
     */
    public $urlCreator;

    /**
     *
     * @var array html options to be applied to the [[initDefaultButton()|default button]].
     * @since 2.0.4
     */
    public $buttonOptions = [];

    /**
     * @inheritdoc
     */
    public function init()
    {
        parent::init();
        $this->initDefaultButtons();
    }

    /**
     * Initializes the default button rendering callbacks.
     */
    protected function initDefaultButtons()
    {
        $this->initDefaultButton('view', 'eye-open');
        $this->initDefaultButton('update', 'pencil');
        $this->initDefaultButton('delete', 'trash', [
            'data-confirm' => Kant::t('kant', 'Are you sure you want to delete this item?'),
            'data-method' => 'post'
        ]);
    }

    /**
     * Initializes the default button rendering callback for single button
     * 
     * @param string $name
     *            Button name as it's written in template
     * @param string $iconName
     *            The part of Bootstrap glyphicon class that makes it unique
     * @param array $additionalOptions
     *            Array of additional options
     * @since 2.0.11
     */
    protected function initDefaultButton($name, $iconName, $additionalOptions = [])
    {
        if (!isset($this->buttons[$name]) && strpos($this->template, '{' . $name . '}') !== false) {
            $this->buttons[$name] = function ($url, $model, $key) use($name, $iconName, $additionalOptions) {
                $title = Kant::t('kant', ucfirst($name));
                $options = array_merge([
                    'title' => $title,
                    'aria-label' => $title,
                    'data-pjax' => '0'
                ], $additionalOptions, $this->buttonOptions);
                $icon = Html::tag('span', '', [
                    'class' => "glyphicon glyphicon-$iconName"
                ]);
                return Html::a($icon, $url, $options);
            };
        }
    }

    /**
     * Creates a URL for the given action and model.
     * This method is called for each button and each row.
     * 
     * @param string $action
     *            the button name (or action ID)
     * @param \Kant\Database\ActiveRecord $model
     *            the data model
     * @param mixed $key
     *            the key associated with the data model
     * @param int $index
     *            the current row index
     * @return string the created URL
     */
    public function createUrl($action, $model, $key, $index)
    {
        if (is_callable($this->urlCreator)) {
            return call_user_func($this->urlCreator, $action, $model, $key, $index, $this);
        } else {
            $params = is_array($key) ? $key : [
                'id' => (string) $key
            ];
            $dispatcher = Kant::$app->dispatcher;
            $dispatcher[2] = $action;
            return Url::to(implode("/", $dispatcher), $params);
        }
    }

    /**
     * @inheritdoc
     */
    protected function renderDataCellContent($model, $key, $index)
    {
        return preg_replace_callback('/\\{([\w\-\/]+)\\}/', function ($matches) use($model, $key, $index) {
            $name = $matches[1];
            
            if (isset($this->visibleButtons[$name])) {
                $isVisible = $this->visibleButtons[$name] instanceof \Closure ? call_user_func($this->visibleButtons[$name], $model, $key, $index) : $this->visibleButtons[$name];
            } else {
                $isVisible = true;
            }
            
            if ($isVisible && isset($this->buttons[$name])) {
                $url = $this->createUrl($name, $model, $key, $index);
                return call_user_func($this->buttons[$name], $url, $model, $key);
            } else {
                return '';
            }
        }, $this->template);
    }
}
