import type { TaskDetail } from "../api";

interface Props {
  detail: TaskDetail | null;
  loading: boolean;
  error: string | null;
  onClose: () => void;
}

function fmtDuration(s: number | null): string {
  if (s == null) return "—";
  if (s < 60) return `${s.toFixed(1)}s`;
  if (s < 3600) return `${(s / 60).toFixed(1)}m`;
  return `${(s / 3600).toFixed(1)}h`;
}

function fmtCost(usd: number): string {
  return usd > 0 ? `$${usd.toFixed(4)}` : "—";
}

// Right-hand drawer: a task's journey through the pipeline (vertical timeline of
// task_transitions) plus Q&A, review verdicts, plan summary, and total spend.
export function TaskDrawer({ detail, loading, error, onClose }: Props) {
  if (!detail && !loading && !error) return null;

  return (
    <section className="drawer" aria-label="task detail" role="complementary">
      <div className="drawer-head">
        <h2>Task history</h2>
        <button className="drawer-close" aria-label="Close detail" onClick={onClose}>
          ✕
        </button>
      </div>

      {loading && <div className="drawer-loading">Loading…</div>}
      {error && <div className="drawer-error">{error}</div>}

      {detail && detail.ok && (
        <>
          <div className="drawer-summary">
            <div className="drawer-task">{detail.task}</div>
            <div className="drawer-meta">
              <span className={`badge ${detail.status}`}>{detail.status}</span>
              <span className="mono">{detail.short_id}</span>
              <span className="spend">spend {fmtCost(detail.total_usd)}</span>
            </div>
            {detail.partial && (
              <div className="partial-banner">
                Partial history — recorded since the v3 ledger; earlier steps are
                reconstructed.
              </div>
            )}
          </div>

          <ol className="timeline">
            {detail.timeline.map((step, i) => {
              const open = step.exited_at == null;
              return (
                <li className={`tl-step ${open ? "open" : ""}`} key={i}>
                  <span className="tl-dot" aria-hidden />
                  <div className="tl-body">
                    <div className="tl-node">{step.to_phase}</div>
                    <div className="tl-times">
                      <span>{step.entered_at ?? "—"}</span>
                      <span className="tl-dur">
                        {open ? "in progress" : fmtDuration(step.duration_s)}
                      </span>
                    </div>
                    <div className="tl-foot">
                      {step.status && <span className={`badge ${step.status}`}>{step.status}</span>}
                      <span className="tl-cost">{fmtCost(step.cost_usd)}</span>
                      {step.note && <span className="tl-note">{step.note}</span>}
                    </div>
                  </div>
                </li>
              );
            })}
            {detail.timeline.length === 0 && (
              <li className="empty">No transitions recorded.</li>
            )}
          </ol>

          {detail.qa_history.length > 0 && (
            <details className="drawer-section" open>
              <summary>Q&amp;A ({detail.qa_history.length})</summary>
              <pre className="json">{JSON.stringify(detail.qa_history, null, 2)}</pre>
            </details>
          )}
          {detail.review_verdicts.length > 0 && (
            <details className="drawer-section">
              <summary>Review verdicts ({detail.review_verdicts.length})</summary>
              <pre className="json">{JSON.stringify(detail.review_verdicts, null, 2)}</pre>
            </details>
          )}
          {detail.plan && (
            <details className="drawer-section">
              <summary>Plan</summary>
              <pre className="json">{JSON.stringify(detail.plan, null, 2)}</pre>
            </details>
          )}
        </>
      )}

      {detail && !detail.ok && (
        <div className="drawer-error">{detail.error ?? "Could not load task."}</div>
      )}
    </section>
  );
}