package com.mydreamjob.bidirectionalmatch;

import com.mydreamjob.auth.User;
import com.mydreamjob.auth.UserRepository;
import com.mydreamjob.common.exception.BusinessException;
import com.mydreamjob.common.exception.ErrorCode;
import com.mydreamjob.company.Company;
import com.mydreamjob.company.CompanyRepository;
import com.mydreamjob.security.UserRoleGuard;
import lombok.RequiredArgsConstructor;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import java.util.HashMap;
import java.util.Map;

/**
 * 匹配阈值配置：企业 requiredCandidateScore / 学生 requiredHrScore。
 * 规则配置不存在时读取返回默认 60；首次更新时创建。
 */
@Service
@RequiredArgsConstructor
public class MatchRuleService {

    private final UserRoleGuard userRoleGuard;
    private final CompanyMatchRuleRepository companyRuleRepository;
    private final StudentMatchRuleRepository studentRuleRepository;
    private final CompanyRepository companyRepository;
    private final UserRepository userRepository;

    // ── 企业 ──────────────────────────────────────────────────

    @Transactional(readOnly = true)
    public Map<String, Object> getCompanyRule(Long userId) {
        Company company = requireCompany(userId);
        CompanyMatchRule rule = companyRuleRepository.findByCompanyId(company.getId()).orElse(null);
        int required = rule != null ? rule.getRequiredCandidateScore()
                : CompanyMatchRule.DEFAULT_REQUIRED_CANDIDATE_SCORE;
        return companyView(company.getId(), required);
    }

    @Transactional
    public Map<String, Object> updateCompanyRule(Long userId, int requiredCandidateScore) {
        Company company = requireCompany(userId);
        CompanyMatchRule rule = companyRuleRepository.findByCompanyId(company.getId())
                .orElseGet(() -> CompanyMatchRule.builder().companyId(company.getId()).build());
        rule.setRequiredCandidateScore(requiredCandidateScore);
        rule = companyRuleRepository.save(rule);
        return companyView(company.getId(), rule.getRequiredCandidateScore());
    }

    // ── 学生 ──────────────────────────────────────────────────

    @Transactional(readOnly = true)
    public Map<String, Object> getStudentRule(Long userId) {
        userRoleGuard.requireStudent(userId);
        StudentMatchRule rule = studentRuleRepository.findByStudentUserId(userId).orElse(null);
        int required = rule != null ? rule.getRequiredHrScore()
                : StudentMatchRule.DEFAULT_REQUIRED_HR_SCORE;
        return studentView(userId, required);
    }

    @Transactional
    public Map<String, Object> updateStudentRule(Long userId, int requiredHrScore) {
        userRoleGuard.requireStudent(userId);
        StudentMatchRule rule = studentRuleRepository.findByStudentUserId(userId)
                .orElseGet(() -> StudentMatchRule.builder().studentUserId(userId).build());
        rule.setRequiredHrScore(requiredHrScore);
        rule = studentRuleRepository.save(rule);
        return studentView(userId, rule.getRequiredHrScore());
    }

    // ── 视图 / 私有 ───────────────────────────────────────────

    private Map<String, Object> companyView(Long companyId, int required) {
        Map<String, Object> v = new HashMap<>();
        v.put("companyId", companyId);
        v.put("requiredCandidateScore", required);
        return v;
    }

    private Map<String, Object> studentView(Long studentUserId, int required) {
        Map<String, Object> v = new HashMap<>();
        v.put("studentUserId", studentUserId);
        v.put("requiredHrScore", required);
        return v;
    }

    private Company requireCompany(Long userId) {
        User user = userRepository.findById(userId)
                .orElseThrow(() -> new BusinessException(ErrorCode.USER_NOT_FOUND));
        boolean isCompany = user.getRoles() != null
                && user.getRoles().stream().anyMatch(r -> r == User.Role.COMPANY);
        if (!isCompany) throw new BusinessException(ErrorCode.FORBIDDEN);
        return companyRepository.findByOwnerUserId(userId)
                .orElseThrow(() -> new BusinessException(ErrorCode.COMPANY_NOT_FOUND));
    }

}