/**
 * @file ai-proxies.js (routes)
 * @description CRUD for AI Proxy profiles — the endpoints behind the
 * **AI Proxy** page of Settings, mounted at `/api/ai-proxies` and, for a
 * client older than the rename, `/api/ai-routers`. CHOOSING a profile is not
 * here: a new session names one (`proxy` on `POST /api/lanes/:id/start` and
 * `POST /api/run`).
 *
 * An edit or a delete here does reach the sessions using it: each reads the
 * profile through a file written at its spawn (`server/lib/proxy-apply.js`),
 * which an edit rewrites and a delete removes.
 *
 * Who may write what (server mode; local mode has no user and writes the
 * shared store as before): an admin writes the SHARED profiles; anyone may
 * keep PERSONAL ones (`scope: "personal"`, a member's only kind), and only
 * their owner lists, edits, deletes or tests them — another user, an admin
 * included, gets the same 404 as a profile that does not exist. An analyst
 * keeps personal ones like a developer.
 *
 * No response on this router carries key material. `GET /` returns the store's
 * public view (`hasKey: true|false`), and there is deliberately no
 * `GET /:name` — a route that returned one profile in full would be the one
 * way an API key could leave this process.
 *
 * `GET /9router` only says whether a `9router` binary is on the server's PATH,
 * so the page can offer a link to its own config UI; it never runs it.
 *
 * @author Nguyễn Ngọc Trí Vĩ <vinnt@smartgift.vn>
 */

const path = require("node:path");
const express = require("express");

const proxies = require("../lib/ai-proxies");
const { refreshProfileFiles, removeProfileFiles } = require("../lib/proxy-apply");
const { sameOriginGuard } = require("../lib/same-origin");
const { which } = require("../lib/ai-tools");
const { shellPath } = require("../lib/shell-path");

const router = express.Router();

const ERR_TO_STATUS = {
  EBADKEY: 400,
  EBADNAME: 400,
  EBADLABEL: 400,
  EBADURL: 400,
  EBADMODEL: 400,
  EBADJSON: 409,
  EBUILTIN: 409,
  ENOTFOUND: 404,
  EADMIN: 403,
};

const notFound = (name) =>
  Object.assign(new Error(`no proxy profile named '${name}'`), { code: "ENOTFOUND" });
const adminOnly = () =>
  Object.assign(new Error("only an admin may change a shared AI Proxy"), { code: "EADMIN" });

/** Throw unless this request may edit or delete profile `name`. */
function assertMayWrite(req, name) {
  const owner = proxies.ownerOfName(name);
  if (owner != null) {
    if (req.user?.id !== owner) throw notFound(name);
  } else if (req.user && req.user.role !== "admin") {
    throw adminOnly();
  }
}

function fail(res, e) {
  const status = ERR_TO_STATUS[e.code] || 500;
  return res.status(status).json({ error: { code: e.code || "EINTERNAL", message: e.message } });
}

// GET /api/ai-proxies — every profile, built-in `native` first. Never a key.
router.get("/", (req, res) => {
  try {
    res.json(proxies.listProxies(req.user?.id ?? null));
  } catch (e) {
    return fail(res, e);
  }
});

// GET /api/ai-proxies/9router — is 9router installed here? `{ installed }`.
// A file lookup on PATH only; nothing is spawned.
router.get("/9router", (_req, res) => {
  const pathStr = [shellPath(), process.env.PATH].filter(Boolean).join(path.delimiter);
  res.json({ installed: Boolean(which("9router", pathStr)) });
});

// POST /api/ai-proxies — body: { label, baseUrl, apiKey?, model, models?,
// behavesAs?, scope? }. `scope` is "shared" (an admin's default) or "personal"
// (a member's only choice); local mode has no user and always writes shared.
router.post("/", sameOriginGuard, (req, res) => {
  try {
    const body = req.body || {};
    const user = req.user;
    const personal = Boolean(user) && (user.role !== "admin" || body.scope === "personal");
    if (user && body.scope === "shared" && user.role !== "admin") throw adminOnly();
    res.status(201).json(proxies.createProxy(body, personal ? user.id : null));
  } catch (e) {
    return fail(res, e);
  }
});

// POST /api/ai-proxies/test — does this endpoint + key + model actually answer,
// for Claude Code (`/v1/messages`) and for Codex (`/v1/responses`)?
// Body: `{ baseUrl, model, apiKey?, name? }`. Registered before `/:name` for
// clarity; no collision today, since `/:name` takes no POST.
//
// A reachable proxy is a 200 here whatever it replies — `{ claude, codex }`,
// each `{ ok, status, message }` with the proxy's own words, which is the whole
// point. Only bad input is a 4xx. The response never echoes the key, including
// on the path where the stored one was used (see `testProxy` on why that path
// is narrow).
router.post("/test", sameOriginGuard, async (req, res) => {
  try {
    const body = { ...(req.body || {}) };
    // The stored-key fallback is the owner's alone: a name that is someone
    // else's personal profile is dropped, so their key is never sent.
    const owner = proxies.ownerOfName(body.name);
    if (owner != null && req.user?.id !== owner) delete body.name;
    res.json(await proxies.testProxy(body));
  } catch (e) {
    return fail(res, e);
  }
});

// PATCH /api/ai-proxies/:name — same fields, all optional. An omitted `apiKey`
// keeps the stored one; the edit form cannot show a key, so it cannot echo one.
//
// A session reads the profile through a file written at its spawn, so the
// edit rewrites those files too — a rotated key reaches live Claude sessions.
router.patch("/:name", sameOriginGuard, (req, res) => {
  try {
    assertMayWrite(req, req.params.name);
    const saved = proxies.updateProxy(req.params.name, req.body || {});
    refreshProfileFiles(saved.name);
    res.json(saved);
  } catch (e) {
    return fail(res, e);
  }
});

// DELETE /api/ai-proxies/:name — and the session files that copy its key.
router.delete("/:name", sameOriginGuard, (req, res) => {
  try {
    assertMayWrite(req, req.params.name);
    const removed = proxies.removeProxy(req.params.name);
    removeProfileFiles(req.params.name);
    res.json(removed);
  } catch (e) {
    return fail(res, e);
  }
});

module.exports = router;