<?php

namespace Aiko;

use Exception;

class Validator
{

    private $request = [];
    private $rules =  [];
    private $errorBag = [];
    public $valid = [];

    public function __construct($request, $rules = [])
    {
        $this->rules = $rules;
        if (!is_array($request) && is_object($request)) {
            $this->request = json_decode(json_encode($request), true);
        } else {
            $this->request = $request;
        }
    }

    /**
     * @param string $paramKey
     * @param \Closure($value, $params): string|null $validatorFn
     */
    public function addRule($paramKey, $validatorFn, $messages = [])
    {
        array_push($this->rules, new ValidationRule($this->request, $paramKey, $validatorFn, $messages));
        return $this;
    }

    public function fails()
    {
        return count($this->errorBag) > 0;
    }
    
    public function safe($key = null)
    {
        if (is_null($key)) {
            return $this->valid;
        }
        if (isset($this->valid[$key])) {
            return $this->valid[$key];
        }
        return null;
    }

    public function all()
    {
        return $this->request;
    }
    
    public function only($keys = []) 
    {
        $request = [];
        foreach ($keys as $key) {
            if (array_key_exists($key, $this->request)) {
                $request[$key] = $this->request[$key];
            }
        }
        return $request;
    }

    public function errors()
    {
        return $this->errorBag;
    }

    public function validate($throw = false)
    {
        /** @var ValidationRule $rule */
        foreach ($this->rules as $rule) {
            if (!$rule->validate()) {
                if ($throw) {
                    throw new ValidatorException($rule->key, $rule->errorBag);
                }
                array_push($this->errorBag, $rule->errorBag);
                continue;
            }
            $this->valid[$rule->key] = $rule->getParamValue();
        }
    }
}


class ValidatorException extends Exception
{
    private $data;

    // Redefine the exception so message isn't optional
    public function __construct($message, $data = [], $previous = null)
    {
        parent::__construct($message, 0, $previous);
        $this->data = $data;
    }

    // custom string representation of object
    public function __toString()
    {
        return __CLASS__ . ": [{$this->code}]: {$this->message}\n";
    }

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