const { getDb } = require('../dbPool');

// 날짜 형식 변환 헬퍼 함수 (ISO 8601 -> MySQL DATE)
const formatDate = (dateStr) => {
  if (!dateStr) return null;
  if (typeof dateStr === 'string' && dateStr.includes('T')) {
    return dateStr.split('T')[0]; // ISO 8601 -> YYYY-MM-DD
  }
  return dateStr;
};

// 1. 작업자 생성
const create = async (worker, callback) => {
  try {
    const db = await getDb();
    const {
      worker_name,
      job_type = null,
      join_date = null,
      salary = null,
      annual_leave = null,
      status = 'active'
    } = worker;

    const [result] = await db.query(
      `INSERT INTO workers
       (worker_name, job_type, join_date, salary, annual_leave, status)
       VALUES (?, ?, ?, ?, ?, ?)`,
      [worker_name, job_type, formatDate(join_date), salary, annual_leave, status]
    );

    callback(null, result.insertId);
  } catch (err) {
    console.error('❌ create 함수 에러:', err);
    callback(err);
  }
};

// 2. 전체 조회
const getAll = async (callback) => {
  try {
    const db = await getDb();
    const [rows] = await db.query(`
      SELECT
        *,
        CASE WHEN status = 'active' THEN 1 ELSE 0 END AS is_active
      FROM workers
      ORDER BY worker_id DESC
    `);
    callback(null, rows);
  } catch (err) {
    callback(err);
  }
};

// 3. 단일 조회
const getById = async (worker_id, callback) => {
  try {
    const db = await getDb();
    const [rows] = await db.query(`
      SELECT
        *,
        CASE WHEN status = 'active' THEN 1 ELSE 0 END AS is_active
      FROM workers
      WHERE worker_id = ?
    `, [worker_id]);
    callback(null, rows[0]);
  } catch (err) {
    callback(err);
  }
};

// 4. 작업자 수정
const update = async (worker, callback) => {
  try {
    const db = await getDb();
    const {
      worker_id,
      worker_name,
      job_type,
      status,
      join_date,
      salary,
      annual_leave
    } = worker;

    // 업데이트할 필드만 동적으로 구성
    const updates = [];
    const values = [];

    if (worker_name !== undefined) {
      updates.push('worker_name = ?');
      values.push(worker_name);
    }
    if (job_type !== undefined) {
      updates.push('job_type = ?');
      values.push(job_type);
    }
    if (status !== undefined) {
      updates.push('status = ?');
      values.push(status);
    }
    if (join_date !== undefined) {
      updates.push('join_date = ?');
      values.push(formatDate(join_date));
    }
    if (salary !== undefined) {
      updates.push('salary = ?');
      values.push(salary);
    }
    if (annual_leave !== undefined) {
      updates.push('annual_leave = ?');
      values.push(annual_leave);
    }

    if (updates.length === 0) {
      callback(new Error('업데이트할 필드가 없습니다'));
      return;
    }

    values.push(worker_id); // WHERE 조건용

    const query = `UPDATE workers SET ${updates.join(', ')} WHERE worker_id = ?`;

    console.log('🔍 실행할 SQL:', query);
    console.log('🔍 SQL 파라미터:', values);

    const [result] = await db.query(query, values);

    callback(null, result.affectedRows);
  } catch (err) {
    console.error('❌ update 함수 에러:', err);
    callback(new Error(err.message || String(err)));
  }
};

// 5. 삭제 (외래키 제약조건 처리)
const remove = async (worker_id, callback) => {
  const db = await getDb();
  const conn = await db.getConnection();

  try {
    await conn.beginTransaction();

    console.log(`🗑️ 작업자 삭제 시작: worker_id=${worker_id}`);

    // 안전한 삭제: 각 테이블을 개별적으로 처리하고 오류가 발생해도 계속 진행
    const tables = [
      { name: 'users', query: 'UPDATE users SET worker_id = NULL WHERE worker_id = ?', action: '업데이트' },
      { name: 'Users', query: 'UPDATE Users SET worker_id = NULL WHERE worker_id = ?', action: '업데이트' },
      { name: 'daily_issue_reports', query: 'DELETE FROM daily_issue_reports WHERE worker_id = ?', action: '삭제' },
      { name: 'DailyIssueReports', query: 'DELETE FROM DailyIssueReports WHERE worker_id = ?', action: '삭제' },
      { name: 'work_reports', query: 'DELETE FROM work_reports WHERE worker_id = ?', action: '삭제' },
      { name: 'WorkReports', query: 'DELETE FROM WorkReports WHERE worker_id = ?', action: '삭제' },
      { name: 'daily_work_reports', query: 'DELETE FROM daily_work_reports WHERE worker_id = ?', action: '삭제' },
      { name: 'monthly_worker_status', query: 'DELETE FROM monthly_worker_status WHERE worker_id = ?', action: '삭제' },
      { name: 'worker_groups', query: 'DELETE FROM worker_groups WHERE worker_id = ?', action: '삭제' }
    ];

    for (const table of tables) {
      try {
        const [result] = await conn.query(table.query, [worker_id]);
        if (result.affectedRows > 0) {
          console.log(`✅ ${table.name} 테이블 ${table.action}: ${result.affectedRows}건`);
        }
      } catch (tableError) {
        console.log(`⚠️ ${table.name} 테이블 ${table.action} 실패 (무시): ${tableError.message}`);
      }
    }

    // 마지막으로 작업자 삭제
    const [result] = await conn.query(
      `DELETE FROM workers WHERE worker_id = ?`,
      [worker_id]
    );
    console.log(`✅ 작업자 삭제 완료: ${result.affectedRows}건`);

    await conn.commit();
    callback(null, result.affectedRows);

  } catch (err) {
    await conn.rollback();
    console.error(`❌ 작업자 삭제 오류 (worker_id: ${worker_id}):`, err);
    callback(new Error(`작업자 삭제 중 오류가 발생했습니다: ${err.message}`));
  } finally {
    conn.release();
  }
};

// ✅ 모듈 내보내기 (정상 구조)
module.exports = {
  create,
  getAll,
  getById,
  update,
  remove
};