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

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

const createVisitRequest = async (requestData) => {
  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]
  );

  return result.insertId;
};

const getAllVisitRequests = async (filters = {}) => {
  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 = [];

  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);
  return rows;
};

const getVisitRequestById = async (requestId) => {
  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]
  );
  return rows[0];
};

const updateVisitRequest = async (requestId, requestData) => {
  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]
  );
  return result;
};

const deleteVisitRequest = async (requestId) => {
  const db = await getDb();
  const [result] = await db.query(
    `DELETE FROM workplace_visit_requests WHERE request_id = ?`,
    [requestId]
  );
  return result;
};

const approveVisitRequest = async (requestId, approvedBy) => {
  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]
  );
  return result;
};

const rejectVisitRequest = async (requestId, rejectionData) => {
  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]
  );
  return result;
};

const updateVisitRequestStatus = async (requestId, status) => {
  const db = await getDb();
  const [result] = await db.query(
    `UPDATE workplace_visit_requests
     SET status = ?, updated_at = NOW()
     WHERE request_id = ?`,
    [status, requestId]
  );
  return result;
};

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

const getAllVisitPurposes = async () => {
  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`
  );
  return rows;
};

const getActiveVisitPurposes = async () => {
  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`
  );
  return rows;
};

const createVisitPurpose = async (purposeData) => {
  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]
  );
  return result.insertId;
};

const updateVisitPurpose = async (purposeId, purposeData) => {
  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]
  );
  return result;
};

const deleteVisitPurpose = async (purposeId) => {
  const db = await getDb();
  const [result] = await db.query(
    `DELETE FROM visit_purpose_types WHERE purpose_id = ?`,
    [purposeId]
  );
  return result;
};

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

const createTrainingRecord = async (trainingData) => {
  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]
  );
  return result.insertId;
};

const getTrainingRecordByRequestId = async (requestId) => {
  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]
  );
  return rows[0];
};

const updateTrainingRecord = async (trainingId, trainingData) => {
  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]
  );
  return result;
};

const completeTraining = async (trainingId, signatureData) => {
  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]
  );
  return result;
};

const getTrainingRecords = async (filters = {}) => {
  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);
  return rows;
};

module.exports = {
  createVisitRequest,
  getAllVisitRequests,
  getVisitRequestById,
  updateVisitRequest,
  deleteVisitRequest,
  approveVisitRequest,
  rejectVisitRequest,
  updateVisitRequestStatus,
  getAllVisitPurposes,
  getActiveVisitPurposes,
  createVisitPurpose,
  updateVisitPurpose,
  deleteVisitPurpose,
  createTrainingRecord,
  getTrainingRecordByRequestId,
  updateTrainingRecord,
  completeTraining,
  getTrainingRecords
};