<?php
/**
 * @package   Essential_Grid
 * @author    ThemePunch <info@themepunch.com>
 * @link      https://www.essential-grid.com/
 * @copyright 2024 ThemePunch
 */
if (!defined('ABSPATH')) exit();

class EssGridMemoryUsageInformation
{

	/**
	 * @var bool 
	 */
	private $real_usage;

	/**
	 * @var array 
	 */
	private $statistics = [];

	// Memory Usage Information constructor
	public function __construct($real_usage = false)
	{
		$this->real_usage = $real_usage;
	}

	// Returns current memory usage with or without styling
	public function getCurrentMemoryUsage($with_style = true)
	{
		$mem = memory_get_usage($this->real_usage);
		return ($with_style) ? $this->byteFormat($mem) : $mem;
	}

	// Returns peak of memory usage
	public function getPeakMemoryUsage($with_style = true)
	{
		$mem = memory_get_peak_usage($this->real_usage);
		return ($with_style) ? $this->byteFormat($mem) : $mem;
	}

	// Set memory usage with info
	public function setMemoryUsage($info = '')
	{
		$this->statistics[] = ['time' => time(),
			'info' => $info,
			'memory_usage' => $this->getCurrentMemoryUsage()];
	}

	// Print all memory usage info and memory limit and 
	public function printMemoryUsageInformation()
	{
		echo '<pre>';
		foreach ($this->statistics as $satistic) {
			echo "Time: " . $satistic['time'] .
				" | Memory Usage: " . $satistic['memory_usage'] .
				" | Info: " . $satistic['info'];
			echo "\n";
		}
		echo "\n\n";
		echo "Peak of memory usage: " . $this->getPeakMemoryUsage();
		echo "\n\n";
		echo '</pre>';
	}

	// Set start with default info or some custom info
	public function setStart($info = 'Initial Memory Usage')
	{
		$this->setMemoryUsage($info);
	}

	// Set end with default info or some custom info
	public function setEnd($info = 'Memory Usage at the End')
	{
		$this->setMemoryUsage($info);
	}

	/**
	 * Byte formatting
	 * 
	 * @param int $bytes
	 * @param string $unit
	 * @param int $decimals
	 * @return string
	 */
	private function byteFormat($bytes, $unit = "", $decimals = 2)
	{
		$units = ['B' => 0, 'KB' => 1, 'MB' => 2, 'GB' => 3, 'TB' => 4,
			'PB' => 5, 'EB' => 6, 'ZB' => 7, 'YB' => 8];

		$value = 0;
		if ($bytes > 0) {
			// Generate automatic prefix by bytes 
			// If wrong prefix given
			if (!array_key_exists($unit, $units)) {
				$pow = floor(log($bytes) / log(1024));
				$unit = array_search($pow, $units);
			}

			// Calculate byte value by prefix
			$value = ($bytes / pow(1024, floor($units[$unit])));
		}

		// If decimals is not numeric or decimals is less than 0 
		// then set default value
		if (!is_numeric($decimals) || $decimals < 0) {
			$decimals = 2;
		}

		// Format output
		return sprintf('%.' . $decimals . 'f ' . $unit, $value);
	}

}