<?php

declare(strict_types=1);

namespace App\Services;

class PhoneFormatterService
{
    /**
     * Normalizes a phone number to standard E.164 digits format (without '+').
     * Automatically handles leading zeros and national dialing prefixes.
     *
     * Example Iraq:   07701234567    -> 9647701234567
     * Example Iraq:   +964 0780 1234 -> 9647801234
     * Example Jordan: 0791234567     -> 962791234567
     */
    public static function normalize(string $phone, string $defaultCountryCode = '964'): string
    {
        // 1. Remove all non-digit characters (+, -, spaces, dots, brackets)
        $cleaned = preg_replace('/[^\d]/', '', $phone);

        if (empty($cleaned)) {
            return '';
        }

        // 2. Remove international double-zero prefixes (e.g. 00964 -> 964)
        if (str_starts_with($cleaned, '00')) {
            $cleaned = substr($cleaned, 2);
        }

        // 3. Supported Country Code Detection & Cleaning
        $knownCountryCodes = ['964', '962', '20', '961', '966', '971'];

        foreach ($knownCountryCodes as $cc) {
            if (str_starts_with($cleaned, $cc)) {
                $localPart = substr($cleaned, strlen($cc));
                // Remove any redundant leading zero after country code (e.g. 964 0770... -> 964 770...)
                $localPart = ltrim($localPart, '0');
                return $cc . $localPart;
            }
        }

        // 4. If no recognized country code is attached, treat as national number with default country code
        // Remove leading national zero (e.g. 0770... -> 770...)
        $nationalPart = ltrim($cleaned, '0');

        return $defaultCountryCode . $nationalPart;
    }

    /**
     * Formats normalized number for display in UI.
     * e.g. 9647701234567 -> +964 770 123 4567
     */
    public static function formatDisplay(string $normalized): string
    {
        if (str_starts_with($normalized, '964') && strlen($normalized) === 13) {
            return '+964 ' . substr($normalized, 3, 3) . ' ' . substr($normalized, 6, 3) . ' ' . substr($normalized, 9);
        }
        if (str_starts_with($normalized, '962') && strlen($normalized) === 12) {
            return '+962 ' . substr($normalized, 3, 2) . ' ' . substr($normalized, 5, 3) . ' ' . substr($normalized, 8);
        }
        return '+' . $normalized;
    }
}