<?php

namespace App\Controllers;

use App\Core\Request;
use App\Core\Response;

/**
 * Foundation controller offering model loading, request parsing, and validation helpers.
 */
class BaseController
{
    /**
     * Validate request payload and return array of errors if any fail
     *
     * @param Request $request
     * @param array $rules List of keys and their validation constraints (e.g. ['email' => 'required|email'])
     * @return array Empty if valid, otherwise contains error messages
     */
    protected function validate(Request $request, array $rules): array
    {
        $errors = [];
        $data = $request->getBody();

        foreach ($rules as $field => $constraints) {
            $value = $data[$field] ?? null;
            $constraintsArray = explode('|', $constraints);

            foreach ($constraintsArray as $constraint) {
                if ($constraint === 'required') {
                    if ($value === null || $value === '') {
                        $errors[$field][] = "The {$field} field is required.";
                    }
                } elseif ($constraint === 'email') {
                    if ($value !== null && $value !== '' && !filter_var($value, FILTER_VALIDATE_EMAIL)) {
                        $errors[$field][] = "The {$field} must be a valid email address.";
                    }
                } elseif (strpos($constraint, 'min:') === 0) {
                    $min = (int) substr($constraint, 4);
                    if ($value !== null && strlen((string)$value) < $min) {
                        $errors[$field][] = "The {$field} must be at least {$min} characters.";
                    }
                }
            }
        }

        return $errors;
    }
}