import express from "express";
import { listSessions, getSession, deleteSession, clearMessages, createSession } from "../stores/sessionStore.js";

const router = express.Router();

/**
 * GET /api/sessions — List all sessions
 */
router.get("/", (_req, res) => {
  const sessions = listSessions();
  res.json(sessions);
});

/**
 * POST /api/sessions — Create a new session
 */
router.post("/", (req, res) => {
  const { grade, subject, chapter } = req.body;
  const session = createSession(grade, subject, chapter);
  res.status(201).json(session);
});

/**
 * GET /api/sessions/:id — Get a single session
 */
router.get("/:id", (req, res) => {
  const session = getSession(req.params.id);
  if (!session) {
    return res.status(404).json({ error: "Session not found" });
  }
  res.json(session);
});

/**
 * DELETE /api/sessions/:id — Delete a session
 */
router.delete("/:id", (req, res) => {
  const deleted = deleteSession(req.params.id);
  if (!deleted) {
    return res.status(404).json({ error: "Session not found" });
  }
  res.json({ message: "Session deleted", id: req.params.id });
});

/**
 * PATCH /api/sessions/:id/clear — Clear messages but keep session
 */
router.patch("/:id/clear", (req, res) => {
  const { id } = req.params;
  const session = getSession(id);
  if (!session) {
    return res.status(404).json({ error: "Session not found" });
  }
  clearMessages(id);
  res.json({ message: "Messages cleared", id });
});

export default router;