"use client";

import Link from "next/link";

import {
  kindLabel,
  reasonLabel,
  type InjectionEntity,
} from "@/lib/workbench/injection";
import { useInjection } from "@/lib/workbench/useInjection";

interface ChapterAssistantProps {
  projectId: string;
  chapterNo: number;
}

// 右栏「本章助手」（UX §6.3）。
// 「本章注入（透明）」读 B0 端点，列出确定性选中的设定/角色 + 入选理由徽标——
// 这是「看到的=写章用的」的信任牌（不变量 #6）。「四审」指向审稿页入口。
export function ChapterAssistant({
  projectId,
  chapterNo,
}: ChapterAssistantProps) {
  const injection = useInjection(projectId, chapterNo);
  const selected = injection.data?.selected ?? [];

  return (
    <aside className="hidden border-l border-line bg-panel p-4 lg:block">
      <h2 className="text-sm font-semibold text-ink">本章助手</h2>

      <section className="mt-4">
        <h3 className="text-xs font-semibold uppercase tracking-wide text-ink-soft">
          本章注入（透明）
        </h3>

        {injection.loading ? (
          <p className="mt-2 text-xs text-ink-soft">加载注入信息…</p>
        ) : injection.error ? (
          <p className="mt-2 rounded border border-dashed border-line bg-bg p-3 text-xs text-ink-soft">
            {injection.error}
          </p>
        ) : selected.length === 0 ? (
          <p className="mt-2 rounded border border-dashed border-line bg-bg p-3 text-xs text-ink-soft">
            本章暂无注入实体（先在大纲点名设定/角色）。
          </p>
        ) : (
          <ul className="mt-2 space-y-2">
            {selected.map((entity) => (
              <EntityRow key={`${entity.kind}:${entity.name}`} entity={entity} />
            ))}
          </ul>
        )}
      </section>

      <section className="mt-6">
        <h3 className="text-xs font-semibold uppercase tracking-wide text-ink-soft">
          四审
        </h3>
        <p className="mt-2 text-xs text-ink-soft">
          一致性 / 伏笔 / 文风 / 节奏，在审稿页逐条裁决。
        </p>
        <Link
          href={`/projects/${projectId}/review?chapter=${chapterNo}`}
          className="mt-2 inline-block rounded border border-cinnabar px-3 py-1.5 text-xs text-cinnabar hover:bg-[var(--color-cinnabar-wash)]"
        >
          去审稿 →
        </Link>
      </section>
    </aside>
  );
}

function EntityRow({ entity }: { entity: InjectionEntity }) {
  return (
    <li className="rounded border border-line bg-bg p-2">
      <div className="flex items-center gap-2">
        <span className="rounded bg-panel px-1.5 py-0.5 text-[10px] text-ink-soft">
          {kindLabel(entity.kind)}
        </span>
        <span className="text-sm text-ink">{entity.name}</span>
      </div>
      <div className="mt-1.5 flex flex-wrap gap-1">
        {(entity.reasons ?? []).map((reason) => (
          <span
            key={reason}
            className="rounded bg-[var(--color-cinnabar-wash)] px-1.5 py-0.5 text-[10px] text-cinnabar"
          >
            {reasonLabel(reason)}
          </span>
        ))}
      </div>
    </li>
  );
}