feat(core): add session form service (#34855)

packages/app/src/utils/question-form.ts

@@ -0,0 +1,49 @@
+export type QuestionOption = {
+  value: string
+  label: string
+  description?: string
+}
+
+export type QuestionField = {
+  key: string
+  title?: string
+  description?: string
+  type: "string" | "multiselect"
+  options?: QuestionOption[]
+  custom?: boolean
+}
+
+export type QuestionForm = {
+  id: string
+  sessionID: string
+  mode: "form"
+  metadata?: { [key: string]: unknown }
+  fields: QuestionField[]
+}
+
+export type QuestionAnswer = string[]
+
+export function isQuestionForm(value: unknown): value is QuestionForm {
+  if (typeof value !== "object" || value === null) return false
+  const form = value as { mode?: unknown; metadata?: unknown; fields?: unknown }
+  if (form.mode !== "form") return false
+  if (typeof form.metadata !== "object" || form.metadata === null) return false
+  if ((form.metadata as { kind?: unknown }).kind !== "question") return false
+  return Array.isArray(form.fields) && form.fields.every(isQuestionField)
+}
+
+function isQuestionField(value: unknown): value is QuestionField {
+  if (typeof value !== "object" || value === null) return false
+  const field = value as { type?: unknown }
+  return field.type === "string" || field.type === "multiselect"
+}
+
+export function questionAnswer(fields: ReadonlyArray<QuestionField>, answers: ReadonlyArray<QuestionAnswer>) {
+  const entries = fields.flatMap((field, index): ReadonlyArray<readonly [string, string | string[]]> => {
+    const answer = answers[index] ?? []
+    if (answer.length === 0) return []
+    if (field.type === "multiselect") return [[field.key, answer]]
+    return [[field.key, answer[0] ?? ""]]
+  })
+  return Object.fromEntries(entries)
+}