export interface DelegateRun {
  delegateRunId: string;
  parentRunId: string | null;
  description: string;
  depth: number;
  status: 'success' | 'aborted' | 'needs_user_input' | 'running';
  startTs: string;
  endTs: string | null;
  eventCount: number;
  toolCalls: number;
}

export interface DelegateRunNode extends DelegateRun {
  children: DelegateRunNode[];
}

/** サブタスクジョブに紐づく delegate run のグループ。Task 7 でレンダリングされる。 */
export interface SubtaskDelegateGroup {
  jobId: string;
  issueNumber: number;
  depth: number;
  status: string;
  runs: DelegateRun[];
}

/** GET /:id/delegate-runs のレスポンス型。 */
export interface DelegateRunsResult {
  runs: DelegateRun[];
  subtasks: SubtaskDelegateGroup[];
}

/** delegate run の status に対応する i18n ラベルキーと Tailwind 色クラス。 */
export function delegateStatusBadge(
  status: DelegateRun['status'],
): { labelKey: string; cls: string } {
  switch (status) {
    case 'success': return { labelKey: 'subtasks.delegateStatus.success', cls: 'bg-emerald-100 text-emerald-800' };
    case 'aborted': return { labelKey: 'subtasks.delegateStatus.aborted', cls: 'bg-red-100 text-red-800' };
    case 'needs_user_input': return { labelKey: 'subtasks.delegateStatus.needs_user_input', cls: 'bg-amber-100 text-amber-800' };
    default: return { labelKey: 'subtasks.delegateStatus.running', cls: 'bg-blue-100 text-blue-800' };
  }
}

/** endTs があればそこまで、無ければ now までの経過。clock skew で負にならないようガード。 */
export function formatElapsed(startTs: string, endTs: string | null, now: number): string {
  const end = endTs ? new Date(endTs).getTime() : now;
  const ms = Math.max(0, end - new Date(startTs).getTime());
  if (ms < 1000) return `${ms}ms`;
  if (ms < 60_000) return `${(ms / 1000).toFixed(1)}s`;
  return `${Math.floor(ms / 60_000)}m${Math.floor((ms % 60_000) / 1000)}s`;
}

/**
 * Build a tree from a flat list of DelegateRun records.
 * Runs whose parentRunId is null, or whose parent is not in the set,
 * are treated as roots (orphan fallback — no data loss).
 */
export function buildDelegateRunTree(runs: DelegateRun[]): DelegateRunNode[] {
  const nodes = new Map<string, DelegateRunNode>();
  for (const r of runs) {
    nodes.set(r.delegateRunId, { ...r, children: [] });
  }
  const roots: DelegateRunNode[] = [];
  for (const node of nodes.values()) {
    const parent = node.parentRunId ? nodes.get(node.parentRunId) : undefined;
    if (parent) {
      parent.children.push(node);
    } else {
      roots.push(node);
    }
  }
  return roots;
}