<?php

namespace NoccyLabs\SimpleJWT\Validator;

use NoccyLabs\SimpleJWT\JWTToken;
use NoccyLabs\SimpleJWT\Key\KeyInterface;

class JWTValidator
{
    private $requireHeaders = [];

    private $requireClaims = [];

    private $requireIssuer = [];

    private $requireAudience = [];

    public function __construct()
    {
        $this->requireHeaders = [
            'alg',
            'typ',
        ];
    }

    public function addRequiredClaim(string $name)
    {
        if (!in_array($name, $this->requireClaims)) {
            return;
        }
        $this->requireClaims[] = $name;
    }

    public function requireIssuer($issuer)
    {
        $this->requireIssuer = (array)$issuer;
    }

    public function requireAudience($audience)
    {
        $this->requireAudience = (array)$audience;
    }

    public function validateToken(JWTToken $token)
    {
        if (!$token->isValid()) {
            throw new JWTTokenException("The token is not valid");
        }

        if (!$token->header->hasAll($this->requireHeaders)) {
            throw new JWTHeaderException("The token is missing one or more required headers");
        }

        if (!$token->claims->hasAll($this->requireClaims)) {
            throw new JWTHeaderException("The token is missing one or more required claims");
        }

        if ($this->requireIssuer) {
            $hasIssuer = $token->header->has("iss");
            if ((!$hasIssuer)
            || (!in_array($token->header->get("iss"), $this->requireIssuer)))
                throw new JWTTokenException("Invalid issuer");
        }

        if ($this->requireAudience) {
            $hasAudience = $token->header->has("aud");
            if ((!$hasAudience)
            || (!in_array($token->header->get("aud"), $this->requireAudience)))
                throw new JWTTokenException("Invalid audience");
        }

        return true;
    }

    public function validate(KeyInterface $key, string $raw)
    {
        $token = new JWTToken($key, $raw);
        if ($this->validateToken($token)) {
            return $token;
        }
    }
}