export type SupportTicketStatus =
  | 'PENDING_REVIEW'
  | 'REJECTED'
  | 'DEVELOPING'
  | 'TESTING'
  | 'PASSED'
  | 'PUBLISHED';

export type SupportTicketStatusTransitionContext = {
  linkedTaskCount: number;
  isSuperAdmin: boolean;
  rejectReason?: string;
};

const FORWARD_TRANSITIONS: Record<SupportTicketStatus, SupportTicketStatus[]> = {
  PENDING_REVIEW: ['DEVELOPING', 'REJECTED'],
  DEVELOPING: ['TESTING', 'REJECTED'],
  TESTING: ['PASSED', 'REJECTED'],
  REJECTED: [],
  PASSED: ['PUBLISHED'],
  PUBLISHED: [],
};

/** 技术支持工单批量/人工改状态校验（禁止回退） */
export function validateSupportTicketStatusTransition(
  from: SupportTicketStatus,
  to: SupportTicketStatus,
  ctx: SupportTicketStatusTransitionContext,
): { ok: boolean; message?: string } {
  if (from === to) return { ok: true };

  const allowed = FORWARD_TRANSITIONS[from] ?? [];
  if (!allowed.includes(to)) {
    return { ok: false, message: `不允许从「${from}」变更为「${to}」` };
  }

  if (to === 'REJECTED') {
    if (!ctx.isSuperAdmin) return { ok: false, message: '仅最高管理员可驳回工单' };
    if (!ctx.rejectReason?.trim()) return { ok: false, message: '请填写驳回理由' };
  }

  if (from === 'PENDING_REVIEW' && to === 'DEVELOPING' && ctx.linkedTaskCount < 1) {
    return { ok: false, message: '待评审工单转入开发须至少 1 条关联开发任务' };
  }

  return { ok: true };
}