<?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\Bootstrap;

use Kant\Exception\InvalidConfigException;
use Kant\Helper\ArrayHelper;

/**
 * Progress renders a bootstrap progress bar component.
 *
 * For example,
 *
 * ```php
 * // default with label
 * echo Progress::widget([
 * 'percent' => 60,
 * 'label' => 'test',
 * ]);
 *
 * // styled
 * echo Progress::widget([
 * 'percent' => 65,
 * 'barOptions' => ['class' => 'progress-bar-danger']
 * ]);
 *
 * // striped
 * echo Progress::widget([
 * 'percent' => 70,
 * 'barOptions' => ['class' => 'progress-bar-warning'],
 * 'options' => ['class' => 'progress-striped']
 * ]);
 *
 * // striped animated
 * echo Progress::widget([
 * 'percent' => 70,
 * 'barOptions' => ['class' => 'progress-bar-success'],
 * 'options' => ['class' => 'active progress-striped']
 * ]);
 *
 * // stacked bars
 * echo Progress::widget([
 * 'bars' => [
 * ['percent' => 30, 'options' => ['class' => 'progress-bar-danger']],
 * ['percent' => 30, 'label' => 'test', 'options' => ['class' => 'progress-bar-success']],
 * ['percent' => 35, 'options' => ['class' => 'progress-bar-warning']],
 * ]
 * ]);
 * ```
 * 
 * @see http://getbootstrap.com/components/#progress
 * @author Antonio Ramirez <amigo.cobos@gmail.com>
 * @author Alexander Makarov <sam@rmcreative.ru>
 * @since 2.0
 */
class Progress extends Widget
{

    /**
     *
     * @var string the button label.
     */
    public $label;

    /**
     *
     * @var integer the amount of progress as a percentage.
     */
    public $percent = 0;

    /**
     *
     * @var array the HTML attributes of the bar.
     * @see \Kant\Helper\Html::renderTagAttributes() for details on how attributes are being rendered.
     */
    public $barOptions = [];

    /**
     *
     * @var array a set of bars that are stacked together to form a single progress bar.
     *      Each bar is an array of the following structure:
     *     
     *      ```php
     *      [
     *      // required, the amount of progress as a percentage.
     *      'percent' => 30,
     *      // optional, the label to be displayed on the bar
     *      'label' => '30%',
     *      // optional, array, additional HTML attributes for the bar tag
     *      'options' => [],
     *      ]
     *      ```
     */
    public $bars;

    /**
     * Initializes the widget.
     * If you override this method, make sure you call the parent implementation first.
     */
    public function init()
    {
        parent::init();
        Html::addCssClass($this->options, [
            'widget' => 'progress'
        ]);
    }

    /**
     * Renders the widget.
     */
    public function run()
    {
        BootstrapAsset::register($this->getView());
        return implode("\n", [
            Html::beginTag('div', $this->options),
            $this->renderProgress(),
            Html::endTag('div')
        ]) . "\n";
    }

    /**
     * Renders the progress.
     * 
     * @return string the rendering result.
     * @throws InvalidConfigException if the "percent" option is not set in a stacked progress bar.
     */
    protected function renderProgress()
    {
        if (empty($this->bars)) {
            return $this->renderBar($this->percent, $this->label, $this->barOptions);
        }
        $bars = [];
        foreach ($this->bars as $bar) {
            $label = ArrayHelper::getValue($bar, 'label', '');
            if (!isset($bar['percent'])) {
                throw new InvalidConfigException("The 'percent' option is required.");
            }
            $options = ArrayHelper::getValue($bar, 'options', []);
            $bars[] = $this->renderBar($bar['percent'], $label, $options);
        }
        
        return implode("\n", $bars);
    }

    /**
     * Generates a bar
     * 
     * @param integer $percent
     *            the percentage of the bar
     * @param string $label,
     *            optional, the label to display at the bar
     * @param array $options
     *            the HTML attributes of the bar
     * @return string the rendering result.
     */
    protected function renderBar($percent, $label = '', $options = [])
    {
        $defaultOptions = [
            'role' => 'progressbar',
            'aria-valuenow' => $percent,
            'aria-valuemin' => 0,
            'aria-valuemax' => 100,
            'style' => "width:{$percent}%"
        ];
        $options = array_merge($defaultOptions, $options);
        Html::addCssClass($options, [
            'widget' => 'progress-bar'
        ]);
        
        $out = Html::beginTag('div', $options);
        $out .= $label;
        $out .= Html::tag('span', \Kant::t('kant', '{percent}% Complete', [
            'percent' => $percent
        ]), [
            'class' => 'sr-only'
        ]);
        $out .= Html::endTag('div');
        
        return $out;
    }
}
