const db = require('../db');
const config = require('../config');
const logger = require('../utils/logger');

/**
 * 记录操作日志
 */
function createLog({ approvalCode, instanceId, workflowType, applicantName, applicantPinyin, action, detail }) {
  const stmt = db.prepare(`
    INSERT INTO operation_logs 
    (approval_code, approval_instance_id, workflow_type, applicant_name, applicant_pinyin, action, detail, status)
    VALUES (?, ?, ?, ?, ?, ?, ?, 'running')
  `);
  const result = stmt.run(approvalCode, instanceId, workflowType, applicantName, applicantPinyin, action, detail);
  return result.lastInsertRowid;
}

/**
 * 更新日志状态
 */
function updateLog(logId, status, errorMessage = null) {
  const stmt = db.prepare(`
    UPDATE operation_logs 
    SET status = ?, error_message = ?, finished_at = datetime('now', 'localtime')
    WHERE id = ?
  `);
  stmt.run(status, errorMessage, logId);
}

/**
 * 查询日志（带分页和过滤）
 */
function queryLogs({ page = 1, pageSize = 20, workflowType, status, startDate, endDate, keyword } = {}) {
  let where = 'WHERE 1=1';
  const params = [];

  if (workflowType) {
    where += ' AND workflow_type = ?';
    params.push(workflowType);
  }
  if (status) {
    where += ' AND status = ?';
    params.push(status);
  }
  if (startDate) {
    where += ' AND created_at >= ?';
    params.push(startDate);
  }
  if (endDate) {
    where += ' AND created_at <= ?';
    params.push(endDate + ' 23:59:59');
  }
  if (keyword) {
    where += ' AND (applicant_name LIKE ? OR detail LIKE ? OR approval_instance_id LIKE ?)';
    params.push(`%${keyword}%`, `%${keyword}%`, `%${keyword}%`);
  }

  const countStmt = db.prepare(`SELECT COUNT(*) as total FROM operation_logs ${where}`);
  const { total } = countStmt.get(...params);

  const offset = (page - 1) * pageSize;
  const dataStmt = db.prepare(`
    SELECT * FROM operation_logs ${where} 
    ORDER BY created_at DESC 
    LIMIT ? OFFSET ?
  `);
  const rows = dataStmt.all(...params, pageSize, offset);

  return { total, page, pageSize, rows };
}

/**
 * 清理过期日志（保留 N 天）
 */
function cleanupOldLogs() {
  const retentionDays = config.security.logRetentionDays;
  const stmt = db.prepare(`
    DELETE FROM operation_logs 
    WHERE created_at < datetime('now', 'localtime', '-' || ? || ' days')
  `);
  const result = stmt.run(retentionDays);
  if (result.changes > 0) {
    logger.info(`已清理 ${result.changes} 条过期日志（保留${retentionDays}天）`);
  }
}

/**
 * 检查审批是否已处理（防重复）
 */
function isApprovalProcessed(instanceId) {
  const stmt = db.prepare(`
    SELECT COUNT(*) as count FROM operation_logs 
    WHERE approval_instance_id = ? AND status = 'success'
  `);
  const { count } = stmt.get(instanceId);
  return count > 0;
}

module.exports = {
  createLog,
  updateLog,
  queryLogs,
  cleanupOldLogs,
  isApprovalProcessed,
};