import type { VersionPlan } from './version-plan';

export interface PlanResultPayload {
  resultType?: 'link' | 'file';
  resultTitle?: string;
  resultUrl?: string;
  resultFileName?: string;
  resultFileData?: string;
}

export interface PlanCompletionState {
  checklistTotal: number;
  checklistCompleted: number;
  requirementTotal: number;
  requirementCompleted: number;
  hasResult: boolean;
  canSubmitResult: boolean;
  canComplete: boolean;
  missingReasons: string[];
}

export function hasPlanResult(plan: PlanResultPayload): boolean {
  const hasTitle = Boolean(plan.resultTitle?.trim());
  if (!hasTitle || !plan.resultType) return false;
  if (plan.resultType === 'link') return Boolean(plan.resultUrl?.trim());
  return Boolean(plan.resultFileData || plan.resultFileName);
}

function requiresRequirementCoverage(plan: VersionPlan): boolean {
  return plan.type === 'product' || plan.type === 'ui';
}

function requiresChecklist(plan: VersionPlan): boolean {
  return plan.type === 'research';
}

export function getPlanCompletionState(plan: VersionPlan): PlanCompletionState {
  const tasks = plan.tasks ?? [];
  const checklistTotal = tasks.length;
  const checklistCompleted = tasks.filter((task) => task.status === 'completed').length;

  const linked = plan.linkedRequirementIds ?? [];
  const completed = new Set(plan.completedRequirementIds ?? []);
  const requirementTotal = linked.length;
  const requirementCompleted = linked.filter((id) => completed.has(id)).length;

  const missingReasons: string[] = [];
  if (requiresChecklist(plan) && checklistTotal === 0) missingReasons.push('缺少子任务');
  if (requiresChecklist(plan) && checklistTotal > 0 && checklistCompleted < checklistTotal) missingReasons.push('子任务未全部完成');
  if (requiresRequirementCoverage(plan) && requirementTotal > 0 && requirementCompleted < requirementTotal) {
    missingReasons.push('关联需求未全部覆盖');
  }

  const canSubmitResult = missingReasons.length === 0;
  const hasResult = hasPlanResult(plan);
  if (canSubmitResult && !hasResult) missingReasons.push('尚未提交成果');

  return {
    checklistTotal,
    checklistCompleted,
    requirementTotal,
    requirementCompleted,
    hasResult,
    canSubmitResult,
    canComplete: canSubmitResult && hasResult,
    missingReasons,
  };
}

export function canTogglePlanChecklist(plan: VersionPlan, now: Date = new Date()): boolean {
  return plan.status === 'in_progress' || (plan.status === 'pending' && Boolean(plan.startTime) && new Date(plan.startTime) <= now);
}

export function canEditPlanRequirementCoverage(plan: VersionPlan, now: Date = new Date()): boolean {
  return canTogglePlanChecklist(plan, now);
}