import type { Priority } from './derive';
import { calcActualElapsedHours, type TimeInterval } from './work-hours';

export type BugStatus = 'open' | 'fixing' | 'fixed' | 'verifying' | 'closed' | 'rejected';
export type BugSeverity = 'critical' | 'major' | 'minor' | 'trivial';

export interface BugLog {
  id: string;
  action: 'create' | 'status_change' | 'transfer' | 'resolve';
  fromValue?: string;
  toValue?: string;
  operator: string;
  remark?: string;
  createdAt: string;
}

export interface Bug {
  id: string;
  bugNo: string;
  versionId: string;
  testCaseId: string;
  requirementId?: string;
  title: string;
  description: string;
  severity: BugSeverity;
  priority: Priority;
  reportedBy: string;
  assigneeId: string;
  status: BugStatus;
  images?: string[];
  logs?: BugLog[];
  resolvedAt?: string;
  closedAt?: string;
  resolution?: string;
  estimateHours?: number;
  aiEstimateHours?: number;
  plannedFixAt?: string;
  createdAt: string;
  updatedAt: string;
}

export const BUG_STATUS_LABEL: Record<BugStatus, string> = {
  open: '待修复',
  fixing: '修复中',
  fixed: '已修复',
  verifying: '验证中',
  closed: '已关闭',
  rejected: '已拒绝',
};

export const BUG_STATUS_COLOR: Record<BugStatus, string> = {
  open: 'bg-red-50 text-red-600',
  fixing: 'bg-blue-50 text-blue-600',
  fixed: 'bg-indigo-50 text-indigo-600',
  verifying: 'bg-purple-50 text-purple-600',
  closed: 'bg-emerald-50 text-emerald-600',
  rejected: 'bg-zinc-100 text-zinc-500',
};

export const BUG_SEVERITY_LABEL: Record<BugSeverity, string> = {
  critical: '致命',
  major: '严重',
  minor: '一般',
  trivial: '轻微',
};

export const BUG_SEVERITY_COLOR: Record<BugSeverity, string> = {
  critical: 'bg-red-100 text-red-700',
  major: 'bg-orange-50 text-orange-700',
  minor: 'bg-yellow-50 text-yellow-700',
  trivial: 'bg-zinc-100 text-zinc-600',
};

export const BUG_ALLOWED_TRANSITIONS: Record<BugStatus, BugStatus[]> = {
  open: ['fixing', 'rejected'],
  fixing: ['fixed'],
  fixed: ['verifying'],
  verifying: ['closed', 'open'],
  closed: [],
  rejected: [],
};

export function canBugTransition(from: BugStatus, to: BugStatus): boolean {
  return BUG_ALLOWED_TRANSITIONS[from].includes(to);
}

export function generateBugNo(existingBugs: Bug[]): string {
  const maxNum = existingBugs.reduce((max, b) => {
    const num = parseInt(b.bugNo.replace('BUG-', ''), 10);
    return isNaN(num) ? max : Math.max(max, num);
  }, 0);
  return `BUG-${String(maxNum + 1).padStart(3, '0')}`;
}

export function getBugActualHours(bug: Bug, now: Date = new Date()): number {
  const start = bug.createdAt;
  if (!start) return 0;
  const end = bug.closedAt ?? bug.resolvedAt ?? (bug.status === 'closed' || bug.status === 'rejected' ? bug.updatedAt : now.toISOString());
  return calcActualElapsedHours(start, end);
}

export function aggregateBugActualHours(bugs: Bug[], now: Date = new Date()): number {
  let sum = 0;
  for (const b of bugs) sum += getBugActualHours(b, now);
  return Math.round(sum * 2) / 2;
}

/**
 * 抽取每条 Bug 的 [createdAt, closedAt ?? resolvedAt ?? (终态 updatedAt) ?? now] 时间区间
 * 用于双口径耗时统计（calcTwoMetrics）
 */
export function bugIntervals(bugs: Bug[], now: Date = new Date()): TimeInterval[] {
  const out: TimeInterval[] = [];
  const nowIso = now.toISOString();
  for (const b of bugs) {
    if (!b.createdAt) continue;
    const isTerminal = b.status === 'closed' || b.status === 'rejected';
    const end = b.closedAt ?? b.resolvedAt ?? (isTerminal ? b.updatedAt : nowIso);
    out.push({ start: b.createdAt, end });
  }
  return out;
}