export type KeepPromptKind = 'video' | 'image'

export type KeepPrompt = {
  id: string
  label: string
  text: string
}

export type KeepPromptLists = {
  video: KeepPrompt[]
  image: KeepPrompt[]
}

export const KEEP_PROMPT_MAX = 40
export const KEEP_PROMPT_TEXT_MAX = 500
export const KEEP_PROMPT_LABEL_MAX = 40

export function emptyKeepPrompts(): KeepPromptLists {
  return { video: [], image: [] }
}

export function sanitizeKeepPromptText(raw: unknown) {
  return String(raw || '')
    .replace(/\r\n/g, '\n')
    .replace(/[\0\r]/g, '')
    .trim()
    .slice(0, KEEP_PROMPT_TEXT_MAX)
}

export function sanitizeKeepPromptLabel(raw: unknown, fallback = '') {
  const label = String(raw || '').replace(/\s+/g, ' ').trim().slice(0, KEEP_PROMPT_LABEL_MAX)
  if (label) return label
  const fromText = sanitizeKeepPromptText(fallback).replace(/\s+/g, ' ').slice(0, KEEP_PROMPT_LABEL_MAX)
  return fromText
}

function normalizeItem(raw: unknown): KeepPrompt | null {
  if (!raw || typeof raw !== 'object') return null
  const rec = raw as Record<string, unknown>
  const text = sanitizeKeepPromptText(rec.text)
  if (!text) return null
  const id = String(rec.id || '').trim() || crypto.randomUUID()
  return {
    id,
    label: sanitizeKeepPromptLabel(rec.label, text),
    text
  }
}

export function normalizeKeepPromptList(raw: unknown): KeepPrompt[] {
  if (!Array.isArray(raw)) return []
  const seen = new Set<string>()
  const out: KeepPrompt[] = []
  for (const entry of raw) {
    if (out.length >= KEEP_PROMPT_MAX) break
    const item = normalizeItem(entry)
    if (!item || seen.has(item.id)) continue
    seen.add(item.id)
    out.push(item)
  }
  return out
}

export function normalizeKeepPrompts(raw: unknown): KeepPromptLists {
  if (!raw || typeof raw !== 'object' || Array.isArray(raw)) return emptyKeepPrompts()
  const rec = raw as Record<string, unknown>
  return {
    video: normalizeKeepPromptList(rec.video),
    image: normalizeKeepPromptList(rec.image)
  }
}

export function parseKeepPromptKind(raw: unknown): KeepPromptKind | '' {
  return raw === 'video' || raw === 'image' ? raw : ''
}

export function insertKeepSnippet(text: string, snippet: string) {
  const src = String(text || '')
  const token = sanitizeKeepPromptText(snippet)
  if (!token) return src
  if (src.includes(token)) return src
  if (!src.trim()) return token
  const needsBreak = !/\n$/.test(src)
  return needsBreak ? `${src.trimEnd()}\n${token}` : `${src}${token}`
}