<?php
/**
 * @package         FireBox
 * @version         1.0.0 Free
 * 
 * @author          FirePlugins <info@fireplugins.com>
 * @link            https://www.fireplugins.com
 * @copyright       Copyright © 2021 FirePlugins All Rights Reserved
 * @license         GNU GPLv3 <http://www.gnu.org/licenses/gpl.html> or later
*/

namespace FireBox\Core\Admin\Analytics;

if (!defined('ABSPATH'))
{
	exit; // Exit if accessed directly.
}

use FPFramework\Libs\Registry;

class Metrics
{
    /**
     * Default active metrics
     * 
     * @var  array
     */
    const default_active_metrics = [
        'impressions'
    ];

    /**
     * Toolbar
     * 
     * @var  array
     */
    private $toolbar;

    /**
     * Analytics Metrics
     * 
     * @var  array
     */
    private $metrics;

    /**
     * Metrics Data
     * 
     * @var  array
     */
    private $metrics_data;

    /**
     * Metrics Constructor
     * 
     * @param   array  $toolbar
     * @param   array  $metrics
     * 
     * @return  void
     */
    public function __construct($toolbar = null, $metrics = null)
    {
        if (!$toolbar)
        {
            $toolbar = new Toolbar();
        }
        $this->toolbar = $toolbar;
        
        if (!$metrics)
        {
            // initialize the metrics
            $metrics = $this->initializeMetrics();
        }
        $this->metrics = $metrics;
    }

    /**
     * Init metrics
     * 
     * @return  void
     */
    public function init()
    {
        // hook to render metrics
        add_action('firebox/analytics/metrics', [$this, 'renderMetrics']);
    }

    /**
     * Render metrics
     * 
     * @return  void
     */
    public function renderMetrics()
    {
        firebox()->renderer->admin->render('analytics/metrics/tmpl');
    }

    /**
     * Gets all metric data with chart-related data
     * 
     * @return  array
     */
    public function getMetricsData()
    {
        if ($this->metrics_data)
        {
            return $this->metrics_data;
        }
        
        // set the metrics data
        $this->setMetricsData();
        
        return $this->metrics_data;
    }

    /**
     * Returns the default active metrics
     * 
     * @return  array
     */
    public function getDefaultActiveMetrics()
    {
        return self::default_active_metrics;
    }
    
    /**
     * Returns all metrics labels
     * 
     * @return  array
     */
    public function getMetricsLabels()
    {
        $metrics = [];

        foreach ($this->metrics as $key => $metric)
        {
            if (!$metric instanceof Metric)
            {
                continue;
            }

            $metric->setBasicData();
            
            $metrics[$key] = $metric->getCleanLabel();
        }
        
        return $metrics;
    }

    /**
     * Creates and sets an array of each metric and their data
     * 
     * @return  void
     */
    public function setMetricsData()
    {
        $compareLabels = $this->toolbar->getComparedLabelsFromSelectedToolbarItems();

        // get all db-related metrics
        $extra_data = [
            'data_source' => [ 'db' ]
        ];
        
        // get the metric data
        $data = Helpers\AnalyticsHelper::getData($this->getMetricsKeys(), $this->toolbar->getSelectedToolbarItems(), $extra_data);

        // loop all metrics that depend on other metrics to calculate their data
        foreach ($this->metrics as $key => $metric)
        {
            // skip non-metrics items
            if ($metric->getDataSource() != 'metrics')
            {
                continue;
            }

            // if the metric does not depend on any other metric, skip
            if (empty($metric->getDataSourceInput()))
            {
                continue;
            }

            // get all dependend metrics data
            $metrics_data = [];
            foreach ($metric->getDataSourceInput() as $_metric)
            {
                $metrics_data[$_metric] = $data[$_metric];
            }

            // get the data from the metric
            $newdata = $metric->getMetricDataFromOtherMetrics($metrics_data);
            
            // merge them with the current data
            $data[$key] = array_merge_recursive($data[$key], $newdata);
        }

        $this->metrics_data = $data;
    }

    /**
     * Initialize all metrics items
     * 
     * @return  array
     */
    private function initializeMetrics()
    {
        // get all Metric Namespace Files
        if (!$files = \scandir(__DIR__ . '/Metrics'))
        {
            return [];
        }

        $items = [];

        foreach ($files as $key => $file)
        {
            // ignore unimportant files
            if (in_array($file, ['index.php', '.', '..']))
            {
                continue;
            }

            $file = basename($file, '.php');

            // instantiate class
            $className = '\FireBox\Core\Admin\Analytics\Metrics\\' . $file;

            if (!class_exists($className))
            {
                continue;
            }

            // init metric and fetch its data
            $metric = new $className($this->toolbar);

            // set metric data
            $items[strtolower($file)] = $metric;
        }

        return $items;
    }

    public function getMetricsKeys()
    {
        $keys = [];

        foreach ($this->metrics as $key => $metric)
        {
            $keys[] = $key;
        }
        
        return $keys;
    }
    
    /**
     * Return the metrics
     * 
     * @return  array
     */
    public function getMetrics()
    {
        return $this->metrics;
    }
}