<?php

declare(strict_types=1);

/*
 * The MIT License (MIT)
 *
 * Copyright (c) 2014-2020 Spomky-Labs
 *
 * This software may be modified and distributed under the terms
 * of the MIT license.  See the LICENSE file for details.
 */

namespace Jose\Component\Signature;

use function array_key_exists;
use InvalidArgumentException;

class Signature
{
    /**
     * @var null|string
     */
    private $encodedProtectedHeader;

    /**
     * @var array
     */
    private $protectedHeader;

    /**
     * @var array
     */
    private $header;

    /**
     * @var string
     */
    private $signature;

    public function __construct(string $signature, array $protectedHeader, ?string $encodedProtectedHeader, array $header)
    {
        $this->protectedHeader = null === $encodedProtectedHeader ? [] : $protectedHeader;
        $this->encodedProtectedHeader = $encodedProtectedHeader;
        $this->signature = $signature;
        $this->header = $header;
    }

    /**
     * The protected header associated with the signature.
     */
    public function getProtectedHeader(): array
    {
        return $this->protectedHeader;
    }

    /**
     * The unprotected header associated with the signature.
     */
    public function getHeader(): array
    {
        return $this->header;
    }

    /**
     * The protected header associated with the signature.
     */
    public function getEncodedProtectedHeader(): ?string
    {
        return $this->encodedProtectedHeader;
    }

    /**
     * Returns the value of the protected header of the specified key.
     *
     * @param string $key The key
     *
     * @throws InvalidArgumentException if the header parameter does not exist
     *
     * @return null|mixed Header value
     */
    public function getProtectedHeaderParameter(string $key)
    {
        if ($this->hasProtectedHeaderParameter($key)) {
            return $this->getProtectedHeader()[$key];
        }

        throw new InvalidArgumentException(sprintf('The protected header "%s" does not exist', $key));
    }

    /**
     * Returns true if the protected header has the given parameter.
     *
     * @param string $key The key
     */
    public function hasProtectedHeaderParameter(string $key): bool
    {
        return array_key_exists($key, $this->getProtectedHeader());
    }

    /**
     * Returns the value of the unprotected header of the specified key.
     *
     * @param string $key The key
     *
     * @return null|mixed Header value
     */
    public function getHeaderParameter(string $key)
    {
        if ($this->hasHeaderParameter($key)) {
            return $this->header[$key];
        }

        throw new InvalidArgumentException(sprintf('The header "%s" does not exist', $key));
    }

    /**
     * Returns true if the unprotected header has the given parameter.
     *
     * @param string $key The key
     */
    public function hasHeaderParameter(string $key): bool
    {
        return array_key_exists($key, $this->header);
    }

    /**
     * Returns the value of the signature.
     */
    public function getSignature(): string
    {
        return $this->signature;
    }
}