<?php

namespace classes;

/**
 * Sanitizes user-input fields that are sent to the e-conomic API.
 *
 * Background: e-conomic returns 400 errors when description fields contain
 * certain characters. The known issue is "/" in the order reference field
 * (TRU-188), but we sanitize defensively for all such cases.
 *
 * - sanitizeTextLine(): for plain text lines (reference, notes, po, etc.)
 * - sanitizeProductNumber(): for product identifiers
 * - sanitizeProductDescription(): for product-line descriptions
 * - sanitizeForEconApi(): catch-all for arbitrary user input
 */
class economic_export_sanitizer
{
    /** E-conomic soft limit for a single description line. */
    public const TEXT_LINE_MAX_LENGTH = 250;
    /** E-conomic soft limit for a product description. */
    public const PRODUCT_DESCRIPTION_MAX_LENGTH = 500;
    /** E-conomic soft limit for a product number. */
    public const PRODUCT_NUMBER_MAX_LENGTH = 50;

    /** Characters that are illegal in product numbers on most e-conomic setups. */
    private const PRODUCT_NUMBER_FORBIDDEN = ['/', '\\', ':', '*', '?', '"', '<', '>', '|', "\0"];

    /**
     * Sanitize a value for use in a single-line text description.
     *
     * Transformations (in order):
     * 1. Replaces "/" with "-" (the reported 400 trigger)
     * 2. Strips control characters (\x00-\x1F) except \t and \n
     * 3. Replaces tab with single space
     * 4. Collapses newlines into spaces (text lines are single-line)
     * 5. Collapses runs of spaces to a single space
     * 6. Trims leading/trailing whitespace
     * 7. Truncates to $maxLength with "..." suffix if needed
     */
    public static function sanitizeTextLine(mixed $value, int $maxLength = self::TEXT_LINE_MAX_LENGTH): string
    {
        if ($value === null) {
            return '';
        }
        $text = (string)$value;
        if ($text === '') {
            return '';
        }
        // 1. Strip control characters except \t and \n
        $text = preg_replace('/[\x00-\x08\x0B\x0C\x0E-\x1F\x7F]/u', '', $text);
        // 2. Replace tab with single space
        $text = str_replace("\t", ' ', $text);
        // 3. Collapse newlines to single space (text lines are single-line)
        $text = preg_replace('/[\r\n]+/u', ' ', $text);
        // 4. Replace forward slashes (the reported 400 trigger)
        $text = str_replace('/', '-', $text);
        // 5. Collapse runs of spaces
        $text = preg_replace('/\s+/u', ' ', $text);
        // 6. Trim
        $text = trim($text);
        // 7. Truncate with ellipsis if too long
        if ($maxLength > 3 && mb_strlen($text) > $maxLength) {
            $text = mb_substr($text, 0, $maxLength - 3) . '...';
        } elseif (mb_strlen($text) > $maxLength) {
            $text = mb_substr($text, 0, $maxLength);
        }
        return $text;
    }

    /**
     * Sanitize a product number/identifier.
     *
     * Removes characters that are illegal in product numbers on most
     * e-conomic setups (filesystem-unsafe + path separators).
     */
    public static function sanitizeProductNumber(mixed $value): string
    {
        if ($value === null) {
            return '';
        }
        $text = (string)$value;
        if ($text === '') {
            return '';
        }
        $text = str_replace(self::PRODUCT_NUMBER_FORBIDDEN, '', $text);
        $text = preg_replace('/[\x00-\x1F\x7F]/u', '', $text);
        $text = trim($text);
        if (mb_strlen($text) > self::PRODUCT_NUMBER_MAX_LENGTH) {
            $text = mb_substr($text, 0, self::PRODUCT_NUMBER_MAX_LENGTH);
        }
        return $text;
    }

    /**
     * Sanitize a longer product description.
     */
    public static function sanitizeProductDescription(mixed $value): string
    {
        return self::sanitizeTextLine($value, self::PRODUCT_DESCRIPTION_MAX_LENGTH);
    }

    /**
     * Catch-all sanitizer for any user-input value going to e-conomic.
     * Defaults to text-line rules.
     */
    public static function sanitizeForEconApi(mixed $value): string
    {
        return self::sanitizeTextLine($value);
    }
}