import { ZodError } from "zod";
import type { NextApiRequest, NextApiResponse } from "next";
import { currentAccount } from "@/lib/account";
import { trustedOrigin } from "@/lib/account-crypto";
import { documentInput, parseDocumentXml } from "@/lib/guidance-input";
import {
  discoverDocuments,
  publishDocument,
  resolveDocument,
  withdrawDocument,
} from "@/lib/guidance-store";
import { guidanceXml } from "@/content/guides/catalog";
export default async function handler(
  req: NextApiRequest,
  res: NextApiResponse,
) {
  res.setHeader("Cache-Control", "no-store");
  const path = req.query.path || [];
  if (!Array.isArray(path) || path.length > 1) return res.status(404).end();
  const id = path[0];
  try {
    if (req.method === "GET") {
      if (!id) {
        const author = req.query.author;
        if (
          author !== undefined &&
          (typeof author !== "string" ||
            !/^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$/i.test(
              author,
            ))
        )
          return res.status(400).json({ error: "作者 ID 无效" });
        return res.json({ documents: await discoverDocuments(author) });
      }
      const revision = req.query.revision;
      if (
        revision !== undefined &&
        (typeof revision !== "string" ||
          !/^[1-9][0-9]{0,9}$/.test(revision) ||
          Number(revision) > 2147483647)
      )
        return res.status(400).json({ error: "版本无效" });
      const doc = await resolveDocument(
        id,
        revision === undefined ? undefined : Number(revision),
      );
      if (!doc) return res.status(404).json({ error: "文档或精确版本不存在" });
      if (req.query.format === "xml") {
        res.setHeader("Content-Type", "application/xml; charset=utf-8");
        return res.send(guidanceXml(doc));
      }
      return res.json({ document: doc });
    }
    if (!["POST", "DELETE"].includes(req.method || "")) {
      res.setHeader("Allow", "GET, POST, DELETE");
      return res.status(405).end();
    }
    const request = new Request(
      new URL(
        req.url || "/",
        process.env.ACCOUNT_PUBLIC_ORIGIN || "http://" + req.headers.host,
      ),
      {
        headers: new Headers(
          Object.entries(req.headers).filter(
            ([, v]) => typeof v === "string",
          ) as [string, string][],
        ),
      },
    );
    if (!trustedOrigin(request))
      return res.status(403).json({ error: "请求来源不受信任" });
    const user = await currentAccount(request);
    if (!user) return res.status(401).json({ error: "请先登录已验证邮箱账户" });
    if (req.method === "DELETE")
      return id && (await withdrawDocument(user.id, id))
        ? res.json({ ok: true })
        : res.status(404).json({ error: "无权删除或不存在" });
    const input =
      typeof req.body === "string"
        ? parseDocumentXml(req.body)
        : documentInput.parse(req.body);
    if (id === "preview") {
      const links = await Promise.all(
        input.links.map(async (l) => ({
          ...l,
          resolved: !!(await resolveDocument(l.target, l.revision)),
        })),
      );
      return res.json({ document: input, xml: guidanceXml(input), links });
    }
    if (id && id !== input.id)
      return res.status(400).json({ error: "文档 ID 不匹配" });
    return res
      .status(201)
      .json({ document: await publishDocument(user.id, input) });
  } catch (e) {
    if (e instanceof ZodError)
      return res
        .status(400)
        .json({
          error: "输入不符合协议，请检查以下字段",
          fields: e.issues.slice(0, 12).map((i) => i.path.join(".") || "文档"),
        });
    const message = e instanceof Error ? e.message : "";
    if (message === "INVALID_ID")
      return res
        .status(400)
        .json({
          error: "文档 ID 必须以 user-你的账户ID- 开头，请使用编辑器生成的前缀",
        });
    if (message === "FORBIDDEN")
      return res.status(403).json({ error: "仅作者可编辑" });
    if (message === "CONFLICT" || (e as { code?: string }).code === "23505")
      return res
        .status(409)
        .json({ error: "版本冲突：请加载最新版本，已发布版本不可修改" });
    if (
      e instanceof Error &&
      (e.name === "ZodError" || /XML|实体|元素|属性|协议|链接/.test(message))
    )
      return res.status(400).json({ error: "输入不符合协议" });
    return res.status(503).json({ error: "文档服务暂不可用" });
  }
}
export const config = { api: { bodyParser: { sizeLimit: "128kb" } } };