export interface HandoffRequestFacts {
  source?: 'gitea' | 'youtrack'
  column: 'todo' | 'in-progress' | 'review' | 'done'
  handoffAttachmentId?: string
  handoffRequestFrom?: string
  handoffRequestError?: string
  assignees?: string[]
}

function openReview(issue: HandoffRequestFacts): boolean {
  return issue.source !== 'youtrack' && issue.column === 'review' && !issue.handoffAttachmentId
}

/** 审查列里同事负责的工单，且当前没有别的申请。 */
export function canAskHandoff(issue: HandoffRequestFacts, me: string | undefined): boolean {
  if (!me || !openReview(issue))
    return false
  const assignees = issue.assignees ?? []
  if (assignees.length === 0 || assignees.includes(me))
    return false
  return !issue.handoffRequestFrom
}

/** 申请人在对方回应前可以取消。 */
export function canCancelHandoffRequest(issue: HandoffRequestFacts, me: string | undefined): boolean {
  return !!me && openReview(issue) && issue.handoffRequestFrom === me
}

/** 负责人同意或拒绝。同意会走现有移交。 */
export function handoffRequestNotices(before: HandoffRequestFacts & { number: number }, next: HandoffRequestFacts & { number: number }, me: string): string[] {
  const notices: string[] = []
  if (
    next.handoffRequestFrom
    && next.handoffRequestFrom !== before.handoffRequestFrom
    && next.handoffRequestFrom !== me
    && (next.assignees ?? []).includes(me)
  ) {
    notices.push(`${next.handoffRequestFrom} 想要 #${next.number}`)
  }
  if (before.handoffRequestFrom === me && next.handoffRequestError === 'rejected' && before.handoffRequestError !== 'rejected')
    notices.push(`#${next.number} 的移交申请被拒绝了`)
  if (
    next.handoffRequestFrom === me
    && next.handoffRequestError
    && next.handoffRequestError !== 'rejected'
    && next.handoffRequestError !== before.handoffRequestError
  ) {
    notices.push(`#${next.number} 没交出来：${next.handoffRequestError}`)
  }
  return notices
}

export function canAnswerHandoffRequest(issue: HandoffRequestFacts, me: string | undefined): boolean {
  return !!me
    && openReview(issue)
    && !!issue.handoffRequestFrom
    && (issue.assignees ?? []).includes(me)
}