import { Router } from "express";
import { z } from "zod";
import {
  listConversations,
  createConversation,
  getConversationMessages,
  updateConversationTitle,
  deleteConversation,
  exportConversationAsMarkdown
} from "../services/conversationsService.js";
import { requireUser } from "../middleware/requireUser.js";
import { parseId } from "../middleware/parseId.js";

export const conversationsRouter = Router();

conversationsRouter.get("/", requireUser, async (req, res, next) => {
  try {
    const limit  = z.coerce.number().int().positive().max(100).catch(50).parse(req.query.limit);
    const offset = z.coerce.number().int().nonnegative().catch(0).parse(req.query.offset);
    const items  = await listConversations(req.userId, { limit, offset });
    res.json({ items });
  } catch (err) {
    next(err);
  }
});

conversationsRouter.post("/", requireUser, async (req, res, next) => {
  try {
    const title = z.string().max(200).catch("Nova conversa").parse(req.body?.title);
    const conv = await createConversation(req.userId, title);
    res.json(conv);
  } catch (err) {
    next(err);
  }
});

conversationsRouter.get("/:id/messages", requireUser, parseId, async (req, res, next) => {
  try {
    const msgs = await getConversationMessages(req.params.id, req.userId);
    if (!msgs) return res.status(404).json({ error: "not_found" });
    res.json({ items: msgs });
  } catch (err) {
    next(err);
  }
});

conversationsRouter.patch("/:id", requireUser, parseId, async (req, res, next) => {
  try {
    const title = z.string().min(1).max(200).parse(req.body?.title);
    await updateConversationTitle(req.params.id, req.userId, title);
    res.json({ ok: true });
  } catch (err) {
    next(err);
  }
});

conversationsRouter.delete("/:id", requireUser, parseId, async (req, res, next) => {
  try {
    await deleteConversation(req.params.id, req.userId);
    res.json({ ok: true });
  } catch (err) {
    next(err);
  }
});

conversationsRouter.get("/:id/export", requireUser, parseId, async (req, res, next) => {
  try {
    const markdown = await exportConversationAsMarkdown(req.params.id, req.userId);
    if (markdown == null) return res.status(404).json({ error: "not_found" });
    res.json({ markdown });
  } catch (err) {
    next(err);
  }
});