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

// ==================== 출입 신청 관리 ====================

/**
 * 출입 신청 생성
 */
const createVisitRequest = async (requestData, callback) => {
  try {
    const db = await getDb();
    const {
      requester_id,
      visitor_company,
      visitor_count = 1,
      category_id,
      workplace_id,
      visit_date,
      visit_time,
      purpose_id,
      notes = null
    } = requestData;

    const [result] = await db.query(
      `INSERT INTO workplace_visit_requests
       (requester_id, visitor_company, visitor_count, category_id, workplace_id,
        visit_date, visit_time, purpose_id, notes)
       VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?)`,
      [requester_id, visitor_company, visitor_count, category_id, workplace_id,
       visit_date, visit_time, purpose_id, notes]
    );

    callback(null, result.insertId);
  } catch (err) {
    callback(err);
  }
};

/**
 * 출입 신청 목록 조회 (필터 옵션 포함)
 */
const getAllVisitRequests = async (filters = {}, callback) => {
  try {
    const db = await getDb();
    let query = `
      SELECT
        vr.request_id, vr.requester_id, vr.visitor_company, vr.visitor_count,
        vr.category_id, vr.workplace_id, vr.visit_date, vr.visit_time,
        vr.purpose_id, vr.notes, vr.status,
        vr.approved_by, vr.approved_at, vr.rejection_reason,
        vr.created_at, vr.updated_at,
        u.username as requester_name, u.name as requester_full_name,
        wc.category_name, w.workplace_name,
        vpt.purpose_name,
        approver.username as approver_name
      FROM workplace_visit_requests vr
      INNER JOIN users u ON vr.requester_id = u.user_id
      INNER JOIN workplace_categories wc ON vr.category_id = wc.category_id
      INNER JOIN workplaces w ON vr.workplace_id = w.workplace_id
      INNER JOIN visit_purpose_types vpt ON vr.purpose_id = vpt.purpose_id
      LEFT JOIN users approver ON vr.approved_by = approver.user_id
      WHERE 1=1
    `;

    const params = [];

    // 필터 적용
    if (filters.status) {
      query += ` AND vr.status = ?`;
      params.push(filters.status);
    }

    if (filters.visit_date) {
      query += ` AND vr.visit_date = ?`;
      params.push(filters.visit_date);
    }

    if (filters.start_date && filters.end_date) {
      query += ` AND vr.visit_date BETWEEN ? AND ?`;
      params.push(filters.start_date, filters.end_date);
    }

    if (filters.requester_id) {
      query += ` AND vr.requester_id = ?`;
      params.push(filters.requester_id);
    }

    if (filters.category_id) {
      query += ` AND vr.category_id = ?`;
      params.push(filters.category_id);
    }

    query += ` ORDER BY vr.visit_date DESC, vr.visit_time DESC, vr.created_at DESC`;

    const [rows] = await db.query(query, params);
    callback(null, rows);
  } catch (err) {
    callback(err);
  }
};

/**
 * 출입 신청 상세 조회
 */
const getVisitRequestById = async (requestId, callback) => {
  try {
    const db = await getDb();
    const [rows] = await db.query(
      `SELECT
        vr.request_id, vr.requester_id, vr.visitor_company, vr.visitor_count,
        vr.category_id, vr.workplace_id, vr.visit_date, vr.visit_time,
        vr.purpose_id, vr.notes, vr.status,
        vr.approved_by, vr.approved_at, vr.rejection_reason,
        vr.created_at, vr.updated_at,
        u.username as requester_name, u.name as requester_full_name,
        wc.category_name, w.workplace_name,
        vpt.purpose_name,
        approver.username as approver_name
      FROM workplace_visit_requests vr
      INNER JOIN users u ON vr.requester_id = u.user_id
      INNER JOIN workplace_categories wc ON vr.category_id = wc.category_id
      INNER JOIN workplaces w ON vr.workplace_id = w.workplace_id
      INNER JOIN visit_purpose_types vpt ON vr.purpose_id = vpt.purpose_id
      LEFT JOIN users approver ON vr.approved_by = approver.user_id
      WHERE vr.request_id = ?`,
      [requestId]
    );

    callback(null, rows[0]);
  } catch (err) {
    callback(err);
  }
};

/**
 * 출입 신청 수정
 */
const updateVisitRequest = async (requestId, requestData, callback) => {
  try {
    const db = await getDb();
    const {
      visitor_company,
      visitor_count,
      category_id,
      workplace_id,
      visit_date,
      visit_time,
      purpose_id,
      notes
    } = requestData;

    const [result] = await db.query(
      `UPDATE workplace_visit_requests
       SET visitor_company = ?, visitor_count = ?, category_id = ?, workplace_id = ?,
           visit_date = ?, visit_time = ?, purpose_id = ?, notes = ?, updated_at = NOW()
       WHERE request_id = ?`,
      [visitor_company, visitor_count, category_id, workplace_id,
       visit_date, visit_time, purpose_id, notes, requestId]
    );

    callback(null, result);
  } catch (err) {
    callback(err);
  }
};

/**
 * 출입 신청 삭제
 */
const deleteVisitRequest = async (requestId, callback) => {
  try {
    const db = await getDb();
    const [result] = await db.query(
      `DELETE FROM workplace_visit_requests WHERE request_id = ?`,
      [requestId]
    );
    callback(null, result);
  } catch (err) {
    callback(err);
  }
};

/**
 * 출입 신청 승인
 */
const approveVisitRequest = async (requestId, approvedBy, callback) => {
  try {
    const db = await getDb();
    const [result] = await db.query(
      `UPDATE workplace_visit_requests
       SET status = 'approved', approved_by = ?, approved_at = NOW(), updated_at = NOW()
       WHERE request_id = ?`,
      [approvedBy, requestId]
    );

    callback(null, result);
  } catch (err) {
    callback(err);
  }
};

/**
 * 출입 신청 반려
 */
const rejectVisitRequest = async (requestId, rejectionData, callback) => {
  try {
    const db = await getDb();
    const { approved_by, rejection_reason } = rejectionData;

    const [result] = await db.query(
      `UPDATE workplace_visit_requests
       SET status = 'rejected', approved_by = ?, approved_at = NOW(),
           rejection_reason = ?, updated_at = NOW()
       WHERE request_id = ?`,
      [approved_by, rejection_reason, requestId]
    );

    callback(null, result);
  } catch (err) {
    callback(err);
  }
};

/**
 * 출입 신청 상태 변경
 */
const updateVisitRequestStatus = async (requestId, status, callback) => {
  try {
    const db = await getDb();
    const [result] = await db.query(
      `UPDATE workplace_visit_requests
       SET status = ?, updated_at = NOW()
       WHERE request_id = ?`,
      [status, requestId]
    );

    callback(null, result);
  } catch (err) {
    callback(err);
  }
};

// ==================== 방문 목적 관리 ====================

/**
 * 모든 방문 목적 조회
 */
const getAllVisitPurposes = async (callback) => {
  try {
    const db = await getDb();
    const [rows] = await db.query(
      `SELECT purpose_id, purpose_name, display_order, is_active, created_at
       FROM visit_purpose_types
       ORDER BY display_order ASC, purpose_id ASC`
    );
    callback(null, rows);
  } catch (err) {
    callback(err);
  }
};

/**
 * 활성 방문 목적만 조회
 */
const getActiveVisitPurposes = async (callback) => {
  try {
    const db = await getDb();
    const [rows] = await db.query(
      `SELECT purpose_id, purpose_name, display_order, is_active, created_at
       FROM visit_purpose_types
       WHERE is_active = TRUE
       ORDER BY display_order ASC, purpose_id ASC`
    );
    callback(null, rows);
  } catch (err) {
    callback(err);
  }
};

/**
 * 방문 목적 추가
 */
const createVisitPurpose = async (purposeData, callback) => {
  try {
    const db = await getDb();
    const { purpose_name, display_order = 0, is_active = true } = purposeData;

    const [result] = await db.query(
      `INSERT INTO visit_purpose_types (purpose_name, display_order, is_active)
       VALUES (?, ?, ?)`,
      [purpose_name, display_order, is_active]
    );

    callback(null, result.insertId);
  } catch (err) {
    callback(err);
  }
};

/**
 * 방문 목적 수정
 */
const updateVisitPurpose = async (purposeId, purposeData, callback) => {
  try {
    const db = await getDb();
    const { purpose_name, display_order, is_active } = purposeData;

    const [result] = await db.query(
      `UPDATE visit_purpose_types
       SET purpose_name = ?, display_order = ?, is_active = ?
       WHERE purpose_id = ?`,
      [purpose_name, display_order, is_active, purposeId]
    );

    callback(null, result);
  } catch (err) {
    callback(err);
  }
};

/**
 * 방문 목적 삭제
 */
const deleteVisitPurpose = async (purposeId, callback) => {
  try {
    const db = await getDb();
    const [result] = await db.query(
      `DELETE FROM visit_purpose_types WHERE purpose_id = ?`,
      [purposeId]
    );
    callback(null, result);
  } catch (err) {
    callback(err);
  }
};

// ==================== 안전교육 기록 관리 ====================

/**
 * 안전교육 기록 생성
 */
const createTrainingRecord = async (trainingData, callback) => {
  try {
    const db = await getDb();
    const {
      request_id,
      trainer_id,
      training_date,
      training_start_time,
      training_end_time = null,
      training_topics = null
    } = trainingData;

    const [result] = await db.query(
      `INSERT INTO safety_training_records
       (request_id, trainer_id, training_date, training_start_time, training_end_time, training_topics)
       VALUES (?, ?, ?, ?, ?, ?)`,
      [request_id, trainer_id, training_date, training_start_time, training_end_time, training_topics]
    );

    callback(null, result.insertId);
  } catch (err) {
    callback(err);
  }
};

/**
 * 특정 출입 신청의 안전교육 기록 조회
 */
const getTrainingRecordByRequestId = async (requestId, callback) => {
  try {
    const db = await getDb();
    const [rows] = await db.query(
      `SELECT
        str.training_id, str.request_id, str.trainer_id, str.training_date,
        str.training_start_time, str.training_end_time, str.training_topics,
        str.signature_data, str.completed_at, str.created_at, str.updated_at,
        u.username as trainer_name, u.name as trainer_full_name
      FROM safety_training_records str
      INNER JOIN users u ON str.trainer_id = u.user_id
      WHERE str.request_id = ?`,
      [requestId]
    );

    callback(null, rows[0]);
  } catch (err) {
    callback(err);
  }
};

/**
 * 안전교육 기록 수정
 */
const updateTrainingRecord = async (trainingId, trainingData, callback) => {
  try {
    const db = await getDb();
    const {
      training_date,
      training_start_time,
      training_end_time,
      training_topics
    } = trainingData;

    const [result] = await db.query(
      `UPDATE safety_training_records
       SET training_date = ?, training_start_time = ?, training_end_time = ?,
           training_topics = ?, updated_at = NOW()
       WHERE training_id = ?`,
      [training_date, training_start_time, training_end_time, training_topics, trainingId]
    );

    callback(null, result);
  } catch (err) {
    callback(err);
  }
};

/**
 * 안전교육 완료 (서명 포함)
 */
const completeTraining = async (trainingId, signatureData, callback) => {
  try {
    const db = await getDb();
    const [result] = await db.query(
      `UPDATE safety_training_records
       SET signature_data = ?, completed_at = NOW(), updated_at = NOW()
       WHERE training_id = ?`,
      [signatureData, trainingId]
    );

    callback(null, result);
  } catch (err) {
    callback(err);
  }
};

/**
 * 안전교육 목록 조회 (날짜별 필터)
 */
const getTrainingRecords = async (filters = {}, callback) => {
  try {
    const db = await getDb();
    let query = `
      SELECT
        str.training_id, str.request_id, str.trainer_id, str.training_date,
        str.training_start_time, str.training_end_time, str.training_topics,
        str.completed_at, str.created_at, str.updated_at,
        u.username as trainer_name, u.name as trainer_full_name,
        vr.visitor_company, vr.visitor_count, vr.visit_date
      FROM safety_training_records str
      INNER JOIN users u ON str.trainer_id = u.user_id
      INNER JOIN workplace_visit_requests vr ON str.request_id = vr.request_id
      WHERE 1=1
    `;

    const params = [];

    if (filters.training_date) {
      query += ` AND str.training_date = ?`;
      params.push(filters.training_date);
    }

    if (filters.start_date && filters.end_date) {
      query += ` AND str.training_date BETWEEN ? AND ?`;
      params.push(filters.start_date, filters.end_date);
    }

    if (filters.trainer_id) {
      query += ` AND str.trainer_id = ?`;
      params.push(filters.trainer_id);
    }

    query += ` ORDER BY str.training_date DESC, str.training_start_time DESC`;

    const [rows] = await db.query(query, params);
    callback(null, rows);
  } catch (err) {
    callback(err);
  }
};

module.exports = {
  // 출입 신청
  createVisitRequest,
  getAllVisitRequests,
  getVisitRequestById,
  updateVisitRequest,
  deleteVisitRequest,
  approveVisitRequest,
  rejectVisitRequest,
  updateVisitRequestStatus,

  // 방문 목적
  getAllVisitPurposes,
  getActiveVisitPurposes,
  createVisitPurpose,
  updateVisitPurpose,
  deleteVisitPurpose,

  // 안전교육
  createTrainingRecord,
  getTrainingRecordByRequestId,
  updateTrainingRecord,
  completeTraining,
  getTrainingRecords
};