import { useEffect, useState } from "react";

import type { StudioDashboard as StudioDashboardData } from "../../../contracts/studio/contract.ts";
import type { components } from "../../../contracts/studio/generated.ts";
import { useStudio } from "../use-studio.ts";
import { GuardedStudioLink } from "./guarded-studio-link.tsx";

type DocumentSummary = components["schemas"]["DocumentSummary"];

const kindLabel = {
  CASE: "Case",
  REFERENCE: "Reference",
  QUESTION: "Question",
} as const;
const actionLabel = {
  CONTINUE_EDITING: "작성 계속",
  VALIDATE: "검증하기",
  FIX_VALIDATION: "오류 수정",
  CREATE_PREVIEW: "미리보기 만들기",
  PUBLISH: "게시하기",
  NONE: "게시 완료",
} as const;

function WorkRow({ item }: Readonly<{ item: DocumentSummary }>) {
  return (
    <article className="studio-work-row">
      <p className="studio-row-label">{kindLabel[item.kind]}</p>
      <div>
        <h3>
          <GuardedStudioLink href={`/studio/documents/${item.id}/edit`}>
            {item.title || "제목 없는 작업본"}
          </GuardedStudioLink>
        </h3>
        <p>
          {item.project?.label ?? "프로젝트 미지정"} · {actionLabel[item.nextAction]}
        </p>
      </div>
      <time dateTime={item.updatedAt}>
        {new Date(item.updatedAt).toLocaleDateString("ko-KR", {
          timeZone: "Asia/Seoul",
        })}
      </time>
    </article>
  );
}

function WorkSection({
  title,
  items,
  href,
  empty,
}: Readonly<{
  title: string;
  items: DocumentSummary[];
  href: string;
  empty: string;
}>) {
  return (
    <section className="studio-work-section">
      <div className="studio-section-title">
        <h2>{title}</h2>
        <GuardedStudioLink href={href}>전체 보기</GuardedStudioLink>
      </div>
      <div className="studio-work-list">
        {items.length ? (
          items.map((item) => <WorkRow key={item.id} item={item} />)
        ) : (
          <p className="studio-empty-inline">{empty}</p>
        )}
      </div>
    </section>
  );
}

function isAbortError(error: unknown): boolean {
  return error instanceof DOMException && error.name === "AbortError";
}

export function StudioDashboard() {
  const { gateway } = useStudio();
  const [dashboard, setDashboard] = useState<StudioDashboardData | null>(null);
  const [error, setError] = useState("");

  useEffect(() => {
    const controller = new AbortController();
    void gateway.getDashboard({ signal: controller.signal }).then(
      (value) => setDashboard(value),
      (reason: unknown) => {
        if (!isAbortError(reason)) setError("작업 흐름을 불러오지 못했습니다.");
      },
    );
    return () => controller.abort();
  }, [gateway]);

  const validationItems =
    dashboard?.continueWriting.filter((item) =>
      ["VALIDATE", "FIX_VALIDATION", "CREATE_PREVIEW"].includes(item.nextAction),
    ) ?? [];

  return (
    <div className="studio-page studio-dashboard-page">
      <header className="studio-page-top">
        <div className="studio-page-heading">
          <p className="studio-eyebrow">WORKSPACE</p>
          <h1>작업 흐름</h1>
          <p>작성 중인 기록을 이어서 정리하고 검증·게시 흐름으로 연결합니다.</p>
        </div>
        <GuardedStudioLink className="studio-primary-action" href="/studio/documents/new">
          새 문서
        </GuardedStudioLink>
      </header>
      {error ? (
        <p className="studio-screen-error" role="alert">
          {error}
        </p>
      ) : null}
      {!dashboard && !error ? (
        <p className="studio-loading" role="status">
          Studio 요약을 불러오는 중입니다.
        </p>
      ) : null}
      {dashboard ? (
        <>
          <section className="studio-summary-grid" aria-label="Studio 요약">
            <div>
              <span>전체 작업본</span>
              <strong>{dashboard.totals.documents}</strong>
            </div>
            <div>
              <span>검증할 기록</span>
              <strong>{validationItems.length}</strong>
            </div>
            <div>
              <span>게시 준비</span>
              <strong>{dashboard.totals.readyToPublish}</strong>
            </div>
            <div>
              <span>게시 기록</span>
              <strong>{dashboard.totals.publications}</strong>
            </div>
          </section>
          <WorkSection
            title="이어서 작성"
            items={dashboard.continueWriting}
            href="/studio/documents"
            empty="이어서 작성할 문서가 없습니다."
          />
          <WorkSection
            title="검증과 미리보기"
            items={validationItems}
            href="/studio/documents"
            empty="현재 검증할 문서가 없습니다."
          />
          <WorkSection
            title="게시 준비"
            items={dashboard.readyToPublish}
            href="/studio/documents"
            empty="게시 준비가 끝난 문서가 없습니다."
          />
          <section className="studio-work-section">
            <div className="studio-section-title">
              <h2>최근 게시</h2>
              <GuardedStudioLink href="/studio/publications">
                게시 기록 보기
              </GuardedStudioLink>
            </div>
            <div className="studio-work-list">
              {dashboard.recentPublications.length ? (
                dashboard.recentPublications.map((item) => (
                  <article
                    className="studio-work-row"
                    key={item.event.publicationEventId}
                  >
                    <p className="studio-row-label">
                      {item.event.type === "UNPUBLISHED"
                        ? "게시 취소"
                        : item.event.type === "REPUBLISHED"
                          ? "재게시"
                          : "게시"}
                    </p>
                    <div>
                      <h3>{item.document.title}</h3>
                      <p>{item.document.project?.label ?? "프로젝트 미지정"}</p>
                    </div>
                    <time dateTime={item.event.occurredAt}>
                      {new Date(item.event.occurredAt).toLocaleDateString("ko-KR", {
                        timeZone: "Asia/Seoul",
                      })}
                    </time>
                  </article>
                ))
              ) : (
                <p className="studio-empty-inline">아직 게시 기록이 없습니다.</p>
              )}
            </div>
          </section>
        </>
      ) : null}
    </div>
  );
}