<?php
if (isset($_POST['update_settings'])) {
    if (can('settings_view')) {
        $db = db();
        $settings = isset($_POST['settings']) && is_array($_POST['settings']) ? $_POST['settings'] : [];

        $textLimits = [
            'company_name' => 190,
            'ctr_no' => 120,
            'vat_number' => 120,
            'company_phone' => 60,
            'company_email' => 190,
            'company_address' => 500,
            'license_app_name' => 190,
            'smtp_host' => 190,
            'smtp_user' => 190,
            'smtp_pass' => 255,
            'smtp_from_email' => 190,
            'smtp_from_name' => 190,
            'smtp_reply_to' => 190,
            'wablas_api_url' => 255,
            'wablas_token' => 500,
            'wablas_security_key' => 500,
            'wablas_sender' => 190,
            'wablas_invoice_numbers' => 1500,
            'wablas_invoice_template' => 3000,
            'wablas_daily_summary_numbers' => 1500,
            'wablas_daily_summary_template' => 3000,
        ];

        foreach ($textLimits as $key => $limit) {
            if (array_key_exists($key, $settings)) {
                $settings[$key] = substr(trim((string)$settings[$key]), 0, $limit);
            }
        }

        $licenseAppName = trim((string)($settings['license_app_name'] ?? ''));
        $settings['license_app_name'] = $licenseAppName !== '' ? substr($licenseAppName, 0, 190) : '';

        $licenseAppSlug = trim((string)($settings['license_app_slug'] ?? ''));
        $settings['license_app_slug'] = $licenseAppSlug !== '' ? LicenseService::sanitizeAppSlug($licenseAppSlug, true) : '';

        $timezone = trim((string)($settings['timezone'] ?? ''));
        $settings['timezone'] = in_array($timezone, DateTimeZone::listIdentifiers(), true)
            ? $timezone
            : date_default_timezone_get();

        $settings['allow_zero_stock_sell'] = (($settings['allow_zero_stock_sell'] ?? '1') === '0') ? '0' : '1';
        $settings['loyalty_enabled'] = (($settings['loyalty_enabled'] ?? '0') === '1') ? '1' : '0';
        $settings['smtp_enabled'] = (($settings['smtp_enabled'] ?? '0') === '1') ? '1' : '0';
        $settings['wablas_enabled'] = (($settings['wablas_enabled'] ?? '0') === '1') ? '1' : '0';
        $settings['wablas_invoice_enabled'] = (($settings['wablas_invoice_enabled'] ?? '0') === '1') ? '1' : '0';
        $settings['wablas_daily_summary_enabled'] = (($settings['wablas_daily_summary_enabled'] ?? '0') === '1') ? '1' : '0';

        $settings['weight_barcode_mode'] = in_array(($settings['weight_barcode_mode'] ?? 'weight'), ['weight', 'price'], true)
            ? (string)$settings['weight_barcode_mode']
            : 'weight';

        $prefixStart = (int)($settings['weight_barcode_prefix_start'] ?? 20);
        $prefixEnd = (int)($settings['weight_barcode_prefix_end'] ?? 29);
        if ($prefixStart < 20 || $prefixStart > 29) {
            $prefixStart = 20;
        }
        if ($prefixEnd < 20 || $prefixEnd > 29) {
            $prefixEnd = 29;
        }
        if ($prefixStart > $prefixEnd) {
            [$prefixStart, $prefixEnd] = [$prefixEnd, $prefixStart];
        }
        $settings['weight_barcode_prefix_start'] = (string)$prefixStart;
        $settings['weight_barcode_prefix_end'] = (string)$prefixEnd;

        $smtpPortRaw = trim((string)($settings['smtp_port'] ?? ''));
        if ($smtpPortRaw === '') {
            $settings['smtp_port'] = '';
        } else {
            $smtpPort = (int)$smtpPortRaw;
            if ($smtpPort < 1 || $smtpPort > 65535) {
                $smtpPort = 587;
            }
            $settings['smtp_port'] = (string)$smtpPort;
        }

        $settings['smtp_secure'] = in_array(($settings['smtp_secure'] ?? 'tls'), ['tls', 'ssl', 'none'], true)
            ? (string)$settings['smtp_secure']
            : 'tls';

        $wablasApiUrl = trim((string)($settings['wablas_api_url'] ?? ''));
        $settings['wablas_api_url'] = $wablasApiUrl !== '' ? substr(rtrim($wablasApiUrl, '/'), 0, 255) : '';

        $wablasCountryCode = preg_replace('/[^0-9+]/', '', (string)($settings['wablas_default_country_code'] ?? ''));
        $settings['wablas_default_country_code'] = substr($wablasCountryCode, 0, 8);

        $timeFields = [
            'wablas_invoice_time' => '',
            'wablas_daily_summary_time' => '20:00',
        ];
        foreach ($timeFields as $key => $fallback) {
            $timeValue = trim((string)($settings[$key] ?? ''));
            if ($timeValue === '') {
                $settings[$key] = $fallback;
                continue;
            }
            $settings[$key] = preg_match('/^(?:[01]\d|2[0-3]):[0-5]\d$/', $timeValue) ? $timeValue : $fallback;
        }

        foreach (['wablas_invoice_numbers', 'wablas_daily_summary_numbers'] as $numbersKey) {
            $numbersRaw = str_replace(["\r\n", "\r"], "\n", (string)($settings[$numbersKey] ?? ''));
            $parts = preg_split('/[\n,;]+/', $numbersRaw) ?: [];
            $normalizedNumbers = [];
            foreach ($parts as $part) {
                $phone = preg_replace('/[^0-9+]/', '', trim((string)$part));
                if ($phone !== '') {
                    $normalizedNumbers[$phone] = true;
                }
            }
            $settings[$numbersKey] = implode("\n", array_slice(array_keys($normalizedNumbers), 0, 50));
        }

        foreach (['wablas_invoice_template' => 3000, 'wablas_daily_summary_template' => 3000] as $templateKey => $limit) {
            $template = str_replace(["\r\n", "\r"], "\n", (string)($settings[$templateKey] ?? ''));
            $settings[$templateKey] = substr(trim($template), 0, $limit);
        }

        foreach ($settings as $key => $value) {
            if (is_array($value)) {
                continue;
            }
            $value = (string)$value;
            $stmt = $db->prepare("INSERT INTO settings (`key`, `value`) VALUES (?, ?) ON DUPLICATE KEY UPDATE `value` = ?");
            $stmt->execute([$key, $value, $value]);
        }

        $files = ['company_logo', 'favicon', 'manager_signature', 'display_slide_1', 'display_slide_2', 'display_slide_3'];
        foreach ($files as $file_key) {
            if (isset($_FILES[$file_key]) && $_FILES[$file_key]['error'] === 0) {
                $ext = pathinfo($_FILES[$file_key]['name'], PATHINFO_EXTENSION);
                $filename = 'uploads/' . $file_key . '_' . time() . '.' . $ext;
                if (!is_dir('uploads')) {
                    mkdir('uploads', 0777, true);
                }
                if (move_uploaded_file($_FILES[$file_key]['tmp_name'], $filename)) {
                    $stmt = $db->prepare("INSERT INTO settings (`key`, `value`) VALUES (?, ?) ON DUPLICATE KEY UPDATE `value` = ?");
                    $stmt->execute([$file_key, $filename, $filename]);
                }
            }
        }

        $allowedTabs = ['company', 'system', 'branding', 'integrations'];
        $activeTab = strtolower(trim((string)($_POST['settings_active_tab'] ?? 'company')));
        if (!in_array($activeTab, $allowedTabs, true)) {
            $activeTab = 'company';
        }

        redirectWithMessage('Settings updated successfully!', page_url('settings', ['tab' => $activeTab]));
    }
}