<?php
declare(strict_types=1);

if (!function_exists('page_entrypoint_map')) {
    function page_entrypoint_map(): array {
        static $map = [
            'activate' => 'activate.php',
            'dashboard' => 'dashboard.php',
            'pos' => 'pos.php',
            'sales' => 'sales.php',
            'sales_returns' => 'sales_returns.php',
            'purchases' => 'purchases.php',
            'purchase_returns' => 'purchase_returns.php',
            'quotations' => 'quotations.php',
            'lpos' => 'lpos.php',
            'accounting' => 'accounting.php',
            'expense_categories' => 'expense_categories.php',
            'expenses' => 'expenses.php',
            'expense_report' => 'expense_report.php',
            'items' => 'items.php',
            'categories' => 'categories.php',
            'units' => 'units.php',
            'customers' => 'customers.php',
            'suppliers' => 'suppliers.php',
            'customer_statement' => 'customer_statement.php',
            'supplier_statement' => 'supplier_statement.php',
            'cashflow_report' => 'cashflow_report.php',
            'expiry_report' => 'expiry_report.php',
            'low_stock_report' => 'low_stock_report.php',
            'loyalty_history' => 'loyalty_history.php',
            'payment_methods' => 'payment_methods.php',
            'settings' => 'settings.php',
            'devices' => 'devices.php',
            'hr_departments' => 'hr_departments.php',
            'hr_employees' => 'hr_employees.php',
            'hr_attendance' => 'hr_attendance.php',
            'hr_payroll' => 'hr_payroll.php',
            'role_groups' => 'role_groups.php',
            'users' => 'users.php',
            'scale_devices' => 'scale_devices.php',
            'customer_display_settings' => 'customer_display_settings.php',
            'backups' => 'backups.php',
            'logs' => 'logs.php',
            'cash_registers' => 'cash_registers.php',
            'register_sessions' => 'register_sessions.php',
            'outlets' => 'outlets.php',
            'my_profile' => 'my_profile.php',
            'copy_outlet_data' => 'copy_outlet_data.php',
        ];

        return $map;
    }
}

if (!function_exists('page_entry_script')) {
    function page_entry_script(string $page): ?string {
        $page = strtolower(trim($page));
        if ($page === '') {
            return null;
        }

        $map = page_entrypoint_map();
        return $map[$page] ?? null;
    }
}

if (!function_exists('page_from_entry_script')) {
    function page_from_entry_script(?string $scriptName = null): ?string {
        static $reverse = null;
        if ($reverse === null) {
            $reverse = array_flip(page_entrypoint_map());
        }

        $scriptName = strtolower(trim((string)($scriptName ?? basename((string)($_SERVER['SCRIPT_NAME'] ?? '')))));
        if ($scriptName === '') {
            return null;
        }

        return $reverse[$scriptName] ?? null;
    }
}

if (!function_exists('page_url')) {
    function page_url(string $page = 'dashboard', array $params = []): string {
        $targetScript = page_entry_script($page);
        $query = $params;

        if ($targetScript === null) {
            $targetScript = 'index.php';
            if ($page !== '' && strtolower($page) !== 'dashboard') {
                $query = ['page' => $page] + $query;
            }
        }

        $queryString = http_build_query($query);
        return $targetScript . ($queryString !== '' ? '?' . $queryString : '');
    }
}

if (!function_exists('page_normalize_url')) {
    function page_normalize_url(string $url): string {
        $url = trim($url);
        if ($url === '') {
            return $url;
        }

        $parts = parse_url($url);
        if ($parts === false) {
            return $url;
        }

        $query = [];
        if (!empty($parts['query'])) {
            parse_str($parts['query'], $query);
        }

        $page = isset($query['page']) ? strtolower(trim((string)$query['page'])) : '';
        if ($page === '') {
            return $url;
        }

        $targetScript = page_entry_script($page);
        if ($targetScript === null) {
            return $url;
        }

        $path = (string)($parts['path'] ?? '');
        $basename = strtolower(trim($path !== '' ? basename($path) : ''));
        $knownRoutePage = $basename !== '' ? page_from_entry_script($basename) : null;

        if ($path !== '' && str_starts_with($path, '/')) {
            $targetPath = '/' . $targetScript;
        } else {
            $targetPath = $targetScript;
        }

        if ($basename === '' || $basename === 'index.php' || $knownRoutePage !== null) {
            $parts['path'] = $targetPath;
            unset($query['page']);
        } else {
            return $url;
        }

        $normalized = (string)($parts['path'] ?? $targetPath);
        if (!empty($query)) {
            $normalized .= '?' . http_build_query($query);
        }
        if (isset($parts['fragment']) && $parts['fragment'] !== '') {
            $normalized .= '#' . $parts['fragment'];
        }

        return $normalized;
    }
}

if (!function_exists('page_request_is_ajax')) {
    function page_request_is_ajax(): bool {
        return strtolower((string)($_SERVER['HTTP_X_REQUESTED_WITH'] ?? '')) === 'xmlhttprequest';
    }
}

if (!function_exists('page_redirect_legacy_url')) {
    function page_redirect_legacy_url(): void {
        if (PHP_SAPI === 'cli') {
            return;
        }

        if (strtoupper((string)($_SERVER['REQUEST_METHOD'] ?? 'GET')) !== 'GET') {
            return;
        }

        if (!isset($_GET['page']) || page_request_is_ajax()) {
            return;
        }

        $requestUri = (string)($_SERVER['REQUEST_URI'] ?? '');
        if ($requestUri === '') {
            return;
        }

        $normalized = page_normalize_url($requestUri);
        if ($normalized !== '' && $normalized !== $requestUri) {
            header('Location: ' . $normalized, true, 302);
            exit;
        }
    }
}

if (!function_exists('set_route_page_context')) {
    function set_route_page_context(string $page): void {
        $_GET['page'] = $page;
        $_REQUEST['page'] = $page;
    }
}