export type PlanTaskStatus = 'pending' | 'in_progress' | 'completed';

export interface PlanTask {
  id: string;
  title: string;
  status: PlanTaskStatus;
}

export interface VersionPlan {
  id: string;
  versionId: string;
  type: 'research' | 'product' | 'ui';
  title: string;
  owner: string;
  startTime: string;
  endTime: string;
  status: 'pending' | 'in_progress' | 'completed';
  tasks?: PlanTask[];
  completedRequirementIds?: string[];
  linkedRequirementIds?: string[];
  resultType?: 'link' | 'file';
  resultUrl?: string;
  resultFileName?: string;
  resultFileData?: string;
  remark?: string;
  overdueReason?: string;
  actualStartAt?: string;
  createdAt: string;
  completedAt?: string;
  addedBy: string;
}

export type PlanType = VersionPlan['type'];

export function calcPlanProgress(tasks?: PlanTask[]): number {
  if (!tasks || tasks.length === 0) return 0;
  const completed = tasks.filter((t) => t.status === 'completed').length;
  return Math.round((completed / tasks.length) * 100);
}

export function calcLinkedReqProgress(linkedIds?: string[], completedIds?: string[]): number {
  if (!linkedIds || linkedIds.length === 0) return 0;
  const done = (completedIds || []).filter((id) => linkedIds.includes(id)).length;
  return Math.round((done / linkedIds.length) * 100);
}

export function calcPlanDuration(start: string, end: string): { days: number; hours: number } {
  const s = new Date(start).getTime();
  const e = new Date(end).getTime();
  if (isNaN(s) || isNaN(e) || e < s) return { days: 0, hours: 0 };
  const diff = Math.ceil((e - s) / (1000 * 60 * 60 * 24));
  const totalDays = Math.max(1, diff); // 当天开始当天结束至少1天
  return { days: totalDays, hours: totalDays * 8 };
}

export function formatDuration(days: number, _hours: number): string {
  if (days === 0) return '0天';
  return `${days}天`;
}

export function calcTotalDuration(plans: VersionPlan[]): string {
  const today = new Date().toISOString().slice(0, 10);
  const activePlans = plans.filter((p) => p.status !== 'pending' || p.startTime <= today);
  if (activePlans.length === 0) return '0天';

  const intervals = activePlans.map((p) => {
    const start = new Date(p.startTime).getTime();
    const end = p.completedAt
      ? new Date(p.completedAt).getTime()
      : p.startTime <= today
        ? new Date(today).getTime()
        : new Date(p.startTime).getTime();
    return { start, end };
  }).filter((i) => i.end > i.start).sort((a, b) => a.start - b.start);

  if (intervals.length === 0) return '0天';

  let totalMs = 0;
  let currentStart = intervals[0].start;
  let currentEnd = intervals[0].end;

  for (let i = 1; i < intervals.length; i++) {
    if (intervals[i].start <= currentEnd) {
      currentEnd = Math.max(currentEnd, intervals[i].end);
    } else {
      totalMs += currentEnd - currentStart;
      currentStart = intervals[i].start;
      currentEnd = intervals[i].end;
    }
  }
  totalMs += currentEnd - currentStart;

  const totalDays = Math.ceil(totalMs / (1000 * 60 * 60 * 24));
  return `${totalDays}天`;
}