<?php

/*
 * This file is part of the Monolog package.
 *
 * (c) Jordi Boggiano <j.boggiano@seld.be>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace Monolog\Formatter;

use Exception;

/**
 * Normalizes incoming records to remove objects/resources so it's easier to dump to various targets
 *
 * @author Jordi Boggiano <j.boggiano@seld.be>
 */
class NormalizerFormatter implements FormatterInterface
{
    const SIMPLE_DATE = "Y-m-d H:i:s";

    protected $dateFormat;

    /**
     * @param string $dateFormat The format of the timestamp: one supported by DateTime::format
     */
    public function __construct($dateFormat = null)
    {
        $this->dateFormat = $dateFormat ?: static::SIMPLE_DATE;
        if (!function_exists('json_encode')) {
            throw new \RuntimeException('PHP\'s json extension is required to use Monolog\'s NormalizerFormatter');
        }
    }

    /**
     * {@inheritdoc}
     */
    public function format(array $record)
    {
        return $this->normalize($record);
    }

    /**
     * {@inheritdoc}
     */
    public function formatBatch(array $records)
    {
        foreach ($records as $key => $record) {
            $records[$key] = $this->format($record);
        }

        return $records;
    }

    protected function normalize($data)
    {
        if (null === $data || is_scalar($data)) {
            if (is_float($data)) {
                if (is_infinite($data)) {
                    return ($data > 0 ? '' : '-') . 'INF';
                }
                if (is_nan($data)) {
                    return 'NaN';
                }
            }

            return $data;
        }

        if (is_array($data) || $data instanceof \Traversable) {
            $normalized = array();

            $count = 1;
            foreach ($data as $key => $value) {
                if ($count++ >= 1000) {
                    $normalized['...'] = 'Over 1000 items, aborting normalization';
                    break;
                }
                $normalized[$key] = $this->normalize($value);
            }

            return $normalized;
        }

        if ($data instanceof \DateTime) {
            return $data->format($this->dateFormat);
        }

        if (is_object($data)) {
            if ($data instanceof Exception) {
                return $this->normalizeException($data);
            }

            // non-serializable objects that implement __toString stringified
            if (method_exists($data, '__toString') && !$data instanceof \JsonSerializable) {
                $value = (string) $data;
            } else {
                // the rest is json-serialized in some way
                $value = $this->toJson($data, true);
            }

            return sprintf("[object] (%s: %s)", get_class($data), $value);
        }

        if (is_resource($data)) {
            return '[resource]';
        }

        return '[unknown('.gettype($data).')]';
    }

    protected function normalizeException(Exception $e)
    {
        $data = array(
            'class' => get_class($e),
            'message' => $e->getMessage(),
            'code' => $e->getCode(),
            'file' => $e->getFile().':'.$e->getLine(),
        );

        $trace = $e->getTrace();
        foreach ($trace as $frame) {
            if (isset($frame['file'])) {
                $data['trace'][] = $frame['file'].':'.$frame['line'];
            } else {
                // We should again normalize the frames, because it might contain invalid items
                $data['trace'][] = $this->toJson($this->normalize($frame), true);
            }
        }

        if ($previous = $e->getPrevious()) {
            $data['previous'] = $this->normalizeException($previous);
        }

        return $data;
    }

    protected function toJson($data, $ignoreErrors = false)
    {
        // suppress json_encode errors since it's twitchy with some inputs
        if ($ignoreErrors) {
            if (version_compare(PHP_VERSION, '5.4.0', '>=')) {
                return @json_encode($data, JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE);
            }

            return @json_encode($data);
        }

        if (version_compare(PHP_VERSION, '5.4.0', '>=')) {
            $json = json_encode($data, JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE);
        } else {
            $json = json_encode($data);
        }

        if ($json === false) {
            $this->throwEncodeError(json_last_error(), $data);
        }

        return $json;
    }

    /**
     * Throws an exception according to a given code with a customized message
     *
     * @param int   $code return code of json_last_error function
     * @param mixed $data data that was meant to be encoded
     * @throws \RuntimeException
     */
    private function throwEncodeError($code, $data)
    {
        switch ($code) {
            case JSON_ERROR_DEPTH:
                $msg = 'Maximum stack depth exceeded';
                break;
            case JSON_ERROR_STATE_MISMATCH:
                $msg = 'Underflow or the modes mismatch';
                break;
            case JSON_ERROR_CTRL_CHAR:
                $msg = 'Unexpected control character found';
                break;
            case JSON_ERROR_UTF8:
                $msg = 'Malformed UTF-8 characters, possibly incorrectly encoded';
                break;
            default:
                $msg = 'Unknown error';
        }

        throw new \RuntimeException('JSON encoding failed: '.$msg.'. Encoding: '.var_export($data, true));
    }
}
