src/app/api/auth/register/route.ts

import { NextRequest, NextResponse } from 'next/server';
import { UserRepository } from '@/lib/repositories/user-repository';
import { z } from 'zod';

const teachingGradeSchema = z.enum(['kindergarten', 'elementary', 'junior_high', 'senior_high', 'other']);
const positionSchema = z.enum(['homeroom', 'subject', 'administrative', 'none', 'other']);
const teachingExperienceSchema = z.enum(['none', 'less_than_1', '1_to_2', '2_to_5', 'more_than_5', 'other']);
const knownStrategySchema = z.enum(['satir', 'nvc', 'orid', 'sbior', 'unknown', 'other']);

const registerSchema = z.object({
  username: z.string()
    .min(3, '帳號至少需要 3 個字元')
    .max(50, '帳號不能超過 50 個字元')
    .regex(/^[a-zA-Z0-9_.]+$/, '帳號只能使用半形英文字母、數字、底線（_）和句點（.）'),
  teachingGrades: z.array(teachingGradeSchema).optional(),
  teachingGradesOther: z.string().optional(),
  positions: z.array(positionSchema).optional(),
  positionsOther: z.string().optional(),
  teachingExperience: teachingExperienceSchema.optional(),
  teachingExperienceOther: z.string().optional(),
  confidenceLevel: z.number().int().min(1).max(7).optional(),
  knownStrategies: z.array(knownStrategySchema).optional(),
  knownStrategiesOther: z.string().optional(),
});

export async function POST(request: NextRequest) {
  try {
    const body = await request.json();
    const validatedData = registerSchema.parse(body);

    const userRepo = new UserRepository();

    // Check if username already exists
    const existingUser = await userRepo.findByUsername(validatedData.username);
    if (existingUser) {
      return NextResponse.json(
        { error: '此帳號已被使用' },
        { status: 400 }
      );
    }

    // Create new user
    const user = await userRepo.createUser(validatedData);

    return NextResponse.json({
      user: {
        id: user.id,
        username: user.username,
      },
      message: `User registered successfully. Use password '${process.env.BASIC_AUTH_PASSWORD || 'cz-2025'}' to login.`,
    });
  } catch (error) {
    if (error instanceof z.ZodError) {
      const message = error.issues.map(i => i.message).join('；');
      return NextResponse.json(
        { error: message },
        { status: 400 }
      );
    }

    console.error('Registration error:', error);
    return NextResponse.json(
      { error: 'Internal server error' },
      { status: 500 }
    );
  }
}