import Dexie from "dexie"
import { getToken } from "@/libs/auth"
import type { AiCoursewareOutline, AiCoursewarePreferences, AiCoursewareResourceBinding, AiCoursewarePage } from "@/api/aiCourseware"
import type { Slide, SlideTheme } from "@/types/slides"

export type ProtectedPageContent = Pick<AiCoursewarePage, "title" | "subtitle" | "bullets" | "studentContent" | "learningEvidence" | "interaction"> & { studentTask?: string }

export interface AiDraftRecord {
  key: string
  updatedAt: number
  outline?: AiCoursewareOutline
  converted?: { title: string; theme: Partial<SlideTheme>; slides: Slide[] }
  preferences: AiCoursewarePreferences
  extraPrompt: string
  taskId?: string
  resources?: AiCoursewareResourceBinding[]
  protectedContent?: Array<[number, ProtectedPageContent]>
  backup?: { title: string; theme: SlideTheme; slides: Slide[]; width: number; ratio: number }
}
const database = new Dexie("AI_COURSEWARE_DRAFTS")
database.version(1).stores({ drafts: "key,updatedAt" })
const drafts = database.table<AiDraftRecord, string>("drafts")
export async function draftKey(id: string, source: string): Promise<string> {
  const token = getToken()
  if (!token) throw new Error("登录状态不可用，无法保存个人草稿")
  const digest = await crypto.subtle.digest("SHA-256", new TextEncoder().encode(token))
  const owner = Array.from(new Uint8Array(digest), byte => byte.toString(16).padStart(2, "0")).join("")
  return `${owner}:${source}:${id}`
}
export const loadAiDraft = (key: string) => drafts.get(key)
export const saveAiDraft = (record: AiDraftRecord) => drafts.put(JSON.parse(JSON.stringify(record)))