import { useState } from "react";
import { useAsyncData } from "../../lib/useAsyncData";
import { adminDeleteRag, adminIndexRag, adminListRag, adminSearchRag } from "../../lib/api";
import type { AdminRagDoc, AdminRagHit } from "../../lib/types";
import { useAuditStore } from "../audit";
import { Notice, PageHeader } from "../components";
import { Button, Surface, Tag } from "../../components/primitives";

export function RagModule(): React.ReactNode {
  const log = useAuditStore((s) => s.log);
  const { data, loading, error, reload } = useAsyncData(() => adminListRag(), []);
  const [query, setQuery] = useState("");
  const [hits, setHits] = useState<AdminRagHit[]>([]);
  const [searching, setSearching] = useState(false);
  const [notice, setNotice] = useState<string | null>(null);
  // Manual "导入文档" form fields.
  const [docName, setDocName] = useState("");
  const [docDesc, setDocDesc] = useState("");
  const [docContent, setDocContent] = useState("");
  const [importing, setImporting] = useState(false);

  const docs: AdminRagDoc[] = data?.documents ?? [];

  const search = async () => {
    log("rag.search", "ok");
    setSearching(true);
    setNotice(null);
    try {
      const res = await adminSearchRag(query.trim());
      setHits(res.hits);
    } catch (err: unknown) {
      const msg = err instanceof Error ? err.message : "检索失败";
      setNotice(msg);
      setHits([]);
    } finally {
      setSearching(false);
    }
  };

  const remove = async (d: AdminRagDoc) => {
    log("rag.delete", "ok");
    setNotice(null);
    try {
      await adminDeleteRag(d.id);
    } catch (err: unknown) {
      setNotice(err instanceof Error ? err.message : "文档删除为后端 M10 写操作");
    }
  };

  const importDoc = async () => {
    if (!docName.trim() || !docContent.trim()) {
      setNotice("文档名称与内容不能为空");
      return;
    }
    setImporting(true);
    setNotice(null);
    try {
      await adminIndexRag({
        name: docName.trim(),
        desc: docDesc.trim() || undefined,
        content: docContent.trim(),
      });
      log("rag.index", "ok");
      setDocName("");
      setDocDesc("");
      setDocContent("");
      reload();
      setNotice("文档已导入，可按知识库检索。");
    } catch (err: unknown) {
      log("rag.index", "error");
      setNotice(err instanceof Error ? err.message : "导入文档失败");
    } finally {
      setImporting(false);
    }
  };

  return (
    <div className="space-y-5">
      <PageHeader
        title="知识库 RAG"
        subtitle="GET /api/v1/admin/rag · 文档列表(分块/嵌入状态) + POST /rag 导入 + 检索测试"
        actions={
          <Button variant="soft" onClick={reload} disabled={importing}>
            刷新
          </Button>
        }
      />

      {notice ? <Notice tone={notice.includes("失败") || notice.includes("不能为空") ? "err" : "warn"}>{notice}</Notice> : null}

      <Surface className="space-y-3">
        <h3 className="text-sm font-semibold">导入文档（写入项目索引，可分块、可检索）</h3>
        <input
          value={docName}
          onChange={(e) => setDocName(e.target.value)}
          placeholder="文档名称（如：内部知识库.md）…"
          className="w-full rounded-[var(--mu-radius)] bg-[var(--mu-surface-2)] px-3 py-2 text-sm outline-none focus:ring-1 focus:ring-[var(--mu-accent)]"
        />
        <input
          value={docDesc}
          onChange={(e) => setDocDesc(e.target.value)}
          placeholder="描述（可选，作为项目描述）…"
          className="w-full rounded-[var(--mu-radius)] bg-[var(--mu-surface-2)] px-3 py-2 text-sm outline-none focus:ring-1 focus:ring-[var(--mu-accent)]"
        />
        <textarea
          value={docContent}
          onChange={(e) => setDocContent(e.target.value)}
          placeholder="粘贴文档正文，空行分段，后端自动分块并落到项目索引（关键词/行上下文可检索）…"
          rows={6}
          className="w-full resize-y rounded-[var(--mu-radius)] bg-[var(--mu-surface-2)] px-3 py-2 text-sm outline-none focus:ring-1 focus:ring-[var(--mu-accent)]"
        />
        <div className="flex justify-end">
          <Button variant="primary" disabled={importing} onClick={() => void importDoc()}>
            {importing ? "导入中…" : "导入文档"}
          </Button>
        </div>
      </Surface>

      <Surface className="space-y-2">
        <div className="flex items-center gap-2">
          <h3 className="text-sm font-semibold">文档列表</h3>
          <span className="text-xs text-[var(--mu-text-lo)]">
            {loading ? "加载中…" : `${docs.length} 篇`}
          </span>
        </div>
        {loading ? (
          <p className="text-xs text-[var(--mu-text-lo)]">正在从项目索引加载知识文档…</p>
        ) : error ? (
          <p className="text-xs text-[var(--mu-text-lo)]">{error}</p>
        ) : docs.length === 0 ? (
          <p className="text-xs text-[var(--mu-text-lo)]">当前无文档：点『导入文档』导入资料后可按知识库检索。</p>
        ) : (
          docs.map((d) => (
            <div
              key={d.id}
              className="flex items-center gap-2 rounded-[var(--mu-radius)] bg-[var(--mu-surface-2)] px-3 py-2 text-sm"
            >
              <div className="min-w-0">
                <span className="font-medium">{d.name}</span>
                {d.desc ? (
                  <span className="ml-2 truncate text-xs text-[var(--mu-text-lo)]">{d.desc}</span>
                ) : null}
              </div>
              <span className="text-xs text-[var(--mu-text-lo)]">{d.chunks} 分块</span>
              <span className="ml-auto">
                <Tag tone={d.embedded ? "ok" : "warn"}>{d.embedded ? "已嵌入" : "待嵌入"}</Tag>
              </span>
              <Button
                size="sm"
                variant="ghost"
                onClick={() => {
                  if (!confirm(`删除 ${d.name}？`)) return;
                  void remove(d);
                }}
              >
                删除
              </Button>
            </div>
          ))
        )}
      </Surface>

      <Surface className="space-y-3">
        <h3 className="text-sm font-semibold">检索测试</h3>
        <div className="flex gap-2">
          <input
            value={query}
            onChange={(e) => setQuery(e.target.value)}
            onKeyDown={(e) => {
              if (e.key === "Enter" && query.trim()) void search();
            }}
            placeholder="输入查询（命中项目索引或项目记忆）…"
            className="min-w-0 flex-1 rounded-[var(--mu-radius)] bg-[var(--mu-surface-2)] px-3 py-2 text-sm outline-none focus:ring-1 focus:ring-[var(--mu-accent)]"
          />
          <Button variant="primary" onClick={() => void search()} disabled={searching || !query.trim()}>
            {searching ? "检索中…" : "检索"}
          </Button>
        </div>
        {hits.length > 0 ? (
          <div className="space-y-1.5">
            {hits.map((h, i) => (
              <div
                key={`${h.docId}-${h.chapter ?? "mem"}-${i}`}
                className="rounded-[var(--mu-radius-sm)] bg-[var(--mu-surface-2)] px-3 py-2 text-xs"
              >
                <div className="mb-1 flex items-center gap-2">
                  <span className="font-medium text-[var(--mu-text)]">{h.docName}</span>
                  {h.chapter ? (
                    <span className="text-[var(--mu-text-lo)]">#{h.chapter}</span>
                  ) : null}
                  <span className="ml-auto text-[var(--mu-text-lo)]">
                    {h.semantic ? "语义" : "关键词"} · {h.score.toFixed(2)}
                  </span>
                </div>
                <p className="whitespace-pre-wrap text-[var(--mu-text-mid)]">{h.text}</p>
              </div>
            ))}
          </div>
        ) : hits.length === 0 && query.trim() && !searching ? (
          <p className="text-xs text-[var(--mu-text-lo)]">无命中。</p>
        ) : null}
      </Surface>

      <Notice>
        分块/嵌入状态与语义检索：配置了 pgvector / SQLite 向量增强后，后端经真实语义/向量路径返回（非空壳）；
        未配置时走项目索引关键词 + 行上下文（导入文档即时可查）。文档删除为后端 M10 写操作。
      </Notice>
    </div>
  );
}