<?php
declare(strict_types = 1);

namespace SalmonDE\CrashLogger;

use RuntimeException;
use function base64_decode;
use function fclose;
use function fgets;
use function fopen;
use function is_array;
use function json_decode;
use function trim;
use function zlib_decode;

class CrashDumpReader {

	private $filePath;
	private $data = null;

	public function __construct(string $filePath){
		$this->filePath = $filePath;
		$this->readData();
	}

	final private function readData(): void{
		$fileHandle = fopen($this->filePath, 'r');

		$start = false;
		$end = false;

		$data = '';
		while($line = fgets($fileHandle)){
			$line = trim($line);

			if($start === true){
				if($end === false){
					if($line === '===END CRASH DUMP==='){
						$end = true;
						break;
					}else{
						$data .= $line;
					}
				}
			}elseif($line === '===BEGIN CRASH DUMP==='){
				$start = true;
			}
		}
		fclose($fileHandle);

		if($start === true and $end === true and trim($data) !== ''){
			$data = base64_decode($data);
			$data = zlib_decode($data);
			$data = json_decode($data, true);
			$this->data = $data;
		}
	}

	public function hasRead(): bool{
		return is_array($this->data);
	}

	public function getFilePath(): string{
		return $this->filePath;
	}

	public function getData(): ?array{
		return $this->data;
	}

	public function getCreationTime(): int{
		if(!$this->hasRead()){
			throw new RuntimeException('No data was read');
		}

		return $this->data['time'];
	}
}