professor/app/api/session/route.ts

import { NextRequest, NextResponse } from 'next/server';
import { db } from '@/db';
import { savedSessions } from '@/db/schema';
import { getAuthUser } from '@/lib/auth';
import { eq } from 'drizzle-orm';

export async function GET() {
  const authUser = await getAuthUser();
  if (!authUser) return NextResponse.json({ session: null }, { status: 401 });

  const row = await db
    .select()
    .from(savedSessions)
    .where(eq(savedSessions.userId, authUser.userId))
    .get();

  if (!row) return NextResponse.json({ session: null });

  return NextResponse.json({
    session: {
      topicId: row.topicId,
      task: row.taskJson ? JSON.parse(row.taskJson) : null,
      code: row.code,
      messages: row.messagesJson ? JSON.parse(row.messagesJson) : [],
      executionResult: row.executionResultJson ? JSON.parse(row.executionResultJson) : null,
    },
  });
}

export async function PUT(req: NextRequest) {
  const authUser = await getAuthUser();
  if (!authUser) return NextResponse.json({ error: 'Unauthorized' }, { status: 401 });

  const { topicId, task, code, messages, executionResult } = await req.json();

  const existing = await db
    .select()
    .from(savedSessions)
    .where(eq(savedSessions.userId, authUser.userId))
    .get();

  const data = {
    userId: authUser.userId,
    topicId: topicId ?? null,
    taskJson: task ? JSON.stringify(task) : null,
    code: code ?? null,
    messagesJson: messages ? JSON.stringify(messages) : null,
    executionResultJson: executionResult ? JSON.stringify(executionResult) : null,
    updatedAt: new Date().toISOString(),
  };

  if (existing) {
    await db
      .update(savedSessions)
      .set(data)
      .where(eq(savedSessions.userId, authUser.userId));
  } else {
    await db.insert(savedSessions).values({ id: crypto.randomUUID(), ...data });
  }

  return NextResponse.json({ ok: true });
}