fix: improve maintenance and synchronize live conversations

frontend/src/utils/widgetFormValidation.ts

@@ -0,0 +1,56 @@
+import { isValidEmail, type WidgetFormField } from '../types/widget'
+
+/** Validate a widget form field with the same value normalization and bounds
+ * used by backend/app/api/widget_chat.py before accepting a form submission. */
+export function validateWidgetFormField(field: WidgetFormField, value: unknown): string | null {
+  const label = field.label || field.name
+  const valueString = value === null || value === undefined ? '' : String(value).trim()
+
+  if (field.required && valueString === '') {
+    return `${label} 为必填项`
+  }
+  if (valueString === '') return null
+
+  if (field.type === 'email' && !isValidEmail(valueString)) {
+    return '请输入有效的邮箱地址'
+  }
+
+  if (field.type === 'tel') {
+    const digits = valueString.replace(/\D/g, '')
+    if (digits.length < 7 || digits.length > 15) return '请输入有效的电话号码'
+  }
+
+  if (field.type === 'text' || field.type === 'textarea') {
+    const valueLength = [...valueString].length
+    if (field.minLength != null && valueLength < field.minLength) {
+      return `${label} 至少需要 ${field.minLength} 个字符`
+    }
+    // Match the server's text-field contract: maxLength=0 disables the bound.
+    if (field.maxLength && valueLength > field.maxLength) {
+      return `${label} 不能超过 ${field.maxLength} 个字符`
+    }
+  }
+
+  if (field.type === 'number') {
+    const numberPattern = /^[+-]?(?:(?:\d(?:_?\d)*(?:\.(?:\d(?:_?\d)*)?)?|\.\d(?:_?\d)*)(?:e[+-]?\d(?:_?\d)*)?|inf(?:inity)?|nan)$/i
+    if (!numberPattern.test(valueString)) return `${label} 必须是有效数字`
+
+    const specialNumber = /^[+-]?(?:inf(?:inity)?|nan)$/i.test(valueString)
+    const lowerValue = valueString.toLowerCase()
+    const numberValue = specialNumber
+      ? lowerValue.endsWith('nan')
+        ? Number.NaN
+        : valueString.startsWith('-') ? Number.NEGATIVE_INFINITY : Number.POSITIVE_INFINITY
+      : Number(valueString.replace(/_/g, ''))
+    const minimum = field.minLength === undefined ? 0 : field.minLength
+    const maximum = field.maxLength === undefined ? null : field.maxLength
+    if (minimum !== null && numberValue < minimum) {
+      return `${label} 不能小于 ${minimum}`
+    }
+    if (maximum !== null && numberValue > maximum) {
+      return `${label} 不能大于 ${maximum}`
+    }
+  }
+
+  return null
+}