package com.xuqm.tenant.service;

import com.xuqm.common.exception.BusinessException;
import com.xuqm.tenant.dto.CreateSubAccountRequest;
import com.xuqm.tenant.entity.TenantEntity;
import com.xuqm.tenant.repository.TenantRepository;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.security.crypto.password.PasswordEncoder;
import org.springframework.stereotype.Service;

import java.security.SecureRandom;
import java.time.LocalDateTime;
import java.util.Base64;
import java.util.List;
import java.util.UUID;
import java.util.concurrent.TimeUnit;

@Service
public class SubAccountService {

    private final TenantRepository tenantRepository;
    private final PasswordEncoder passwordEncoder;
    private final EmailService emailService;
    private final StringRedisTemplate redis;

    private static final String SUB_VERIFY_PREFIX = "sub_verified:";
    private static final SecureRandom random = new SecureRandom();

    public SubAccountService(TenantRepository tenantRepository, PasswordEncoder passwordEncoder,
                              EmailService emailService, StringRedisTemplate redis) {
        this.tenantRepository = tenantRepository;
        this.passwordEncoder = passwordEncoder;
        this.emailService = emailService;
        this.redis = redis;
    }

    public boolean isEmailVerifiedInSession(String tenantId) {
        return Boolean.TRUE.toString().equals(redis.opsForValue().get(SUB_VERIFY_PREFIX + tenantId));
    }

    public void verifyEmail(String tenantId, String email, String code) {
        emailService.verify(email, code, "SUB_ACCOUNT");
        redis.opsForValue().set(SUB_VERIFY_PREFIX + tenantId, Boolean.TRUE.toString(), 24, TimeUnit.HOURS);
    }

    public TenantEntity create(String parentId, CreateSubAccountRequest req) {
        if (tenantRepository.existsByUsername(req.username())) {
            throw new BusinessException("用户名已存在");
        }

        TenantEntity sub = new TenantEntity();
        sub.setId(UUID.randomUUID().toString());
        sub.setUsername(req.username());
        sub.setPassword(passwordEncoder.encode(req.password()));
        sub.setEmail(req.email() != null ? req.email() : "");
        sub.setNickname(req.nickname());
        sub.setPhone(req.phone());
        sub.setType(TenantEntity.Type.SUB);
        sub.setStatus(TenantEntity.Status.ACTIVE);
        sub.setParentId(parentId);
        sub.setCreatedAt(LocalDateTime.now());
        return tenantRepository.save(sub);
    }

    public List<TenantEntity> listByParent(String parentId) {
        return tenantRepository.findByParentId(parentId);
    }

    public void disable(String subId, String parentId) {
        TenantEntity sub = tenantRepository.findById(subId)
                .orElseThrow(() -> new BusinessException(404, "子账号不存在"));
        if (!parentId.equals(sub.getParentId())) {
            throw new BusinessException(403, "无权操作");
        }
        sub.setStatus(TenantEntity.Status.DISABLED);
        tenantRepository.save(sub);
    }

    public String generatePassword() {
        byte[] bytes = new byte[9];
        random.nextBytes(bytes);
        return Base64.getUrlEncoder().withoutPadding().encodeToString(bytes);
    }
}