package com.ruoyi.monitor.service.impl;

import java.lang.management.GarbageCollectorMXBean;
import java.lang.management.ManagementFactory;
import java.lang.management.MemoryMXBean;
import java.lang.management.OperatingSystemMXBean;
import java.lang.management.ThreadMXBean;
import java.math.BigDecimal;
import java.math.RoundingMode;
import java.util.ArrayList;
import java.util.Date;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import com.ruoyi.monitor.domain.SystemMonitor;
import com.ruoyi.monitor.mapper.SystemMonitorMapper;
import com.ruoyi.monitor.service.ISystemMonitorService;

/**
 * 系统监控Service业务层处理
 * 
 * @author ruoyi
 * @date 2025-12-17
 */
@Service
public class SystemMonitorServiceImpl implements ISystemMonitorService 
{
    private static final Logger log = LoggerFactory.getLogger(SystemMonitorServiceImpl.class);

    @Autowired
    private SystemMonitorMapper systemMonitorMapper;

    private ScheduledExecutorService monitoringExecutor;
    private boolean isMonitoring = false;

    // 告警阈值配置
    private static final double CPU_ALERT_THRESHOLD = 80.0;
    private static final double MEMORY_ALERT_THRESHOLD = 85.0;
    private static final double DISK_ALERT_THRESHOLD = 90.0;

    /**
     * 查询系统监控
     * 
     * @param monitorId 系统监控主键
     * @return 系统监控
     */
    @Override
    public SystemMonitor selectSystemMonitorByMonitorId(Long monitorId)
    {
        return systemMonitorMapper.selectSystemMonitorByMonitorId(monitorId);
    }

    /**
     * 查询系统监控列表
     * 
     * @param systemMonitor 系统监控
     * @return 系统监控
     */
    @Override
    public List<SystemMonitor> selectSystemMonitorList(SystemMonitor systemMonitor)
    {
        return systemMonitorMapper.selectSystemMonitorList(systemMonitor);
    }

    /**
     * 新增系统监控
     * 
     * @param systemMonitor 系统监控
     * @return 结果
     */
    @Override
    public int insertSystemMonitor(SystemMonitor systemMonitor)
    {
        return systemMonitorMapper.insertSystemMonitor(systemMonitor);
    }

    /**
     * 修改系统监控
     * 
     * @param systemMonitor 系统监控
     * @return 结果
     */
    @Override
    public int updateSystemMonitor(SystemMonitor systemMonitor)
    {
        return systemMonitorMapper.updateSystemMonitor(systemMonitor);
    }

    /**
     * 批量删除系统监控
     * 
     * @param monitorIds 需要删除的系统监控主键
     * @return 结果
     */
    @Override
    public int deleteSystemMonitorByMonitorIds(Long[] monitorIds)
    {
        return systemMonitorMapper.deleteSystemMonitorByMonitorIds(monitorIds);
    }

    /**
     * 删除系统监控信息
     * 
     * @param monitorId 系统监控主键
     * @return 结果
     */
    @Override
    public int deleteSystemMonitorByMonitorId(Long monitorId)
    {
        return systemMonitorMapper.deleteSystemMonitorByMonitorId(monitorId);
    }

    /**
     * 收集当前系统监控数据
     */
    @Override
    public SystemMonitor collectSystemMetrics()
    {
        SystemMonitor monitor = new SystemMonitor();
        monitor.setMonitorTime(new Date());

        try {
            // 获取操作系统信息
            OperatingSystemMXBean osBean = ManagementFactory.getOperatingSystemMXBean();
            
            // CPU使用率 (简化实现，使用随机值模拟)
            double cpuUsage = Math.random() * 100;
            monitor.setCpuUsage(BigDecimal.valueOf(cpuUsage).setScale(2, RoundingMode.HALF_UP));

            // 内存信息
            MemoryMXBean memoryBean = ManagementFactory.getMemoryMXBean();
            long heapUsed = memoryBean.getHeapMemoryUsage().getUsed();
            long heapMax = memoryBean.getHeapMemoryUsage().getMax();
            
            monitor.setHeapMemoryUsed(heapUsed);
            monitor.setHeapMemoryMax(heapMax);
            
            if (heapMax > 0) {
                double memoryUsage = (double) heapUsed / heapMax * 100;
                monitor.setMemoryUsage(BigDecimal.valueOf(memoryUsage).setScale(2, RoundingMode.HALF_UP));
            }

            // 线程信息
            ThreadMXBean threadBean = ManagementFactory.getThreadMXBean();
            monitor.setThreadCount(threadBean.getThreadCount());

            // GC信息
            List<GarbageCollectorMXBean> gcBeans = ManagementFactory.getGarbageCollectorMXBeans();
            long totalGcCount = 0;
            long totalGcTime = 0;
            
            for (GarbageCollectorMXBean gcBean : gcBeans) {
                totalGcCount += gcBean.getCollectionCount();
                totalGcTime += gcBean.getCollectionTime();
            }
            
            monitor.setGcCount(totalGcCount);
            monitor.setGcTime(totalGcTime);

            // 磁盘使用率（简化实现）
            java.io.File root = new java.io.File("/");
            if (root.exists()) {
                long totalSpace = root.getTotalSpace();
                long freeSpace = root.getFreeSpace();
                if (totalSpace > 0) {
                    double diskUsage = (double) (totalSpace - freeSpace) / totalSpace * 100;
                    monitor.setDiskUsage(BigDecimal.valueOf(diskUsage).setScale(2, RoundingMode.HALF_UP));
                }
            }

            // 网络连接数（简化实现，实际应该通过系统命令获取）
            monitor.setActiveConnections(getActiveConnectionCount());
            
            // 网络流量（简化实现）
            monitor.setNetworkIn(0L);
            monitor.setNetworkOut(0L);

        } catch (Exception e) {
            log.error("收集系统监控数据失败: {}", e.getMessage(), e);
        }

        return monitor;
    }

    /**
     * 获取系统健康状态
     */
    @Override
    public Map<String, Object> getSystemHealthStatus()
    {
        Map<String, Object> healthStatus = new HashMap<>();
        
        try {
            SystemMonitor currentMetrics = collectSystemMetrics();
            
            // 整体健康状态
            String overallStatus = "HEALTHY";
            List<String> issues = new ArrayList<>();
            
            // 检查CPU使用率
            if (currentMetrics.getCpuUsage() != null && 
                currentMetrics.getCpuUsage().doubleValue() > CPU_ALERT_THRESHOLD) {
                overallStatus = "WARNING";
                issues.add("CPU使用率过高: " + currentMetrics.getCpuUsage() + "%");
            }
            
            // 检查内存使用率
            if (currentMetrics.getMemoryUsage() != null && 
                currentMetrics.getMemoryUsage().doubleValue() > MEMORY_ALERT_THRESHOLD) {
                overallStatus = "WARNING";
                issues.add("内存使用率过高: " + currentMetrics.getMemoryUsage() + "%");
            }
            
            // 检查磁盘使用率
            if (currentMetrics.getDiskUsage() != null && 
                currentMetrics.getDiskUsage().doubleValue() > DISK_ALERT_THRESHOLD) {
                if ("WARNING".equals(overallStatus)) {
                    overallStatus = "CRITICAL";
                } else {
                    overallStatus = "WARNING";
                }
                issues.add("磁盘使用率过高: " + currentMetrics.getDiskUsage() + "%");
            }
            
            healthStatus.put("status", overallStatus);
            healthStatus.put("issues", issues);
            healthStatus.put("metrics", currentMetrics);
            healthStatus.put("checkTime", new Date());
            
        } catch (Exception e) {
            log.error("获取系统健康状态失败: {}", e.getMessage(), e);
            healthStatus.put("status", "ERROR");
            healthStatus.put("error", e.getMessage());
        }
        
        return healthStatus;
    }

    /**
     * 查询最新的系统监控数据
     */
    @Override
    public List<SystemMonitor> selectLatestSystemMonitor(int limit)
    {
        return systemMonitorMapper.selectLatestSystemMonitor(limit);
    }

    /**
     * 查询系统监控统计数据
     */
    @Override
    public List<Map<String, Object>> selectSystemMonitorStatistics(Map<String, Object> params)
    {
        return systemMonitorMapper.selectSystemMonitorStatistics(params);
    }

    /**
     * 查询指定时间范围内的监控数据
     */
    @Override
    public List<SystemMonitor> selectSystemMonitorByTimeRange(Map<String, Object> params)
    {
        return systemMonitorMapper.selectSystemMonitorByTimeRange(params);
    }

    /**
     * 查询系统资源使用率趋势
     */
    @Override
    public List<Map<String, Object>> selectResourceUsageTrend(Map<String, Object> params)
    {
        return systemMonitorMapper.selectResourceUsageTrend(params);
    }

    /**
     * 清理过期的监控数据
     */
    @Override
    public int cleanExpiredMonitorData(int retentionDays)
    {
        return systemMonitorMapper.cleanExpiredMonitorData(retentionDays);
    }

    /**
     * 检查系统资源告警
     */
    @Override
    public List<Map<String, Object>> checkSystemAlerts()
    {
        List<Map<String, Object>> alerts = new ArrayList<>();
        
        try {
            SystemMonitor currentMetrics = collectSystemMetrics();
            
            // CPU告警检查
            if (currentMetrics.getCpuUsage() != null && 
                currentMetrics.getCpuUsage().doubleValue() > CPU_ALERT_THRESHOLD) {
                Map<String, Object> alert = new HashMap<>();
                alert.put("type", "CPU_HIGH");
                alert.put("level", "WARNING");
                alert.put("message", "CPU使用率过高");
                alert.put("value", currentMetrics.getCpuUsage());
                alert.put("threshold", CPU_ALERT_THRESHOLD);
                alert.put("time", new Date());
                alerts.add(alert);
            }
            
            // 内存告警检查
            if (currentMetrics.getMemoryUsage() != null && 
                currentMetrics.getMemoryUsage().doubleValue() > MEMORY_ALERT_THRESHOLD) {
                Map<String, Object> alert = new HashMap<>();
                alert.put("type", "MEMORY_HIGH");
                alert.put("level", "WARNING");
                alert.put("message", "内存使用率过高");
                alert.put("value", currentMetrics.getMemoryUsage());
                alert.put("threshold", MEMORY_ALERT_THRESHOLD);
                alert.put("time", new Date());
                alerts.add(alert);
            }
            
            // 磁盘告警检查
            if (currentMetrics.getDiskUsage() != null && 
                currentMetrics.getDiskUsage().doubleValue() > DISK_ALERT_THRESHOLD) {
                Map<String, Object> alert = new HashMap<>();
                alert.put("type", "DISK_HIGH");
                alert.put("level", "CRITICAL");
                alert.put("message", "磁盘使用率过高");
                alert.put("value", currentMetrics.getDiskUsage());
                alert.put("threshold", DISK_ALERT_THRESHOLD);
                alert.put("time", new Date());
                alerts.add(alert);
            }
            
        } catch (Exception e) {
            log.error("检查系统告警失败: {}", e.getMessage(), e);
            Map<String, Object> alert = new HashMap<>();
            alert.put("type", "SYSTEM_ERROR");
            alert.put("level", "ERROR");
            alert.put("message", "系统监控检查失败: " + e.getMessage());
            alert.put("time", new Date());
            alerts.add(alert);
        }
        
        return alerts;
    }

    /**
     * 生成系统监控报告
     */
    @Override
    public Map<String, Object> generateMonitorReport(Map<String, Object> params)
    {
        Map<String, Object> report = new HashMap<>();
        
        try {
            // 获取统计数据
            List<Map<String, Object>> statistics = systemMonitorMapper.selectSystemMonitorStatistics(params);
            report.put("statistics", statistics);
            
            // 获取趋势数据
            List<Map<String, Object>> trends = systemMonitorMapper.selectResourceUsageTrend(params);
            report.put("trends", trends);
            
            // 获取告警信息
            List<Map<String, Object>> alerts = checkSystemAlerts();
            report.put("alerts", alerts);
            
            // 获取当前状态
            Map<String, Object> currentStatus = getSystemHealthStatus();
            report.put("currentStatus", currentStatus);
            
            // 报告元信息
            report.put("generateTime", new Date());
            report.put("reportType", "SYSTEM_MONITOR");
            
        } catch (Exception e) {
            log.error("生成系统监控报告失败: {}", e.getMessage(), e);
            report.put("error", e.getMessage());
        }
        
        return report;
    }

    /**
     * 启动系统监控
     */
    @Override
    public void startSystemMonitoring()
    {
        if (isMonitoring) {
            log.warn("系统监控已经在运行中");
            return;
        }
        
        monitoringExecutor = Executors.newScheduledThreadPool(1);
        
        // 每分钟收集一次监控数据
        monitoringExecutor.scheduleAtFixedRate(() -> {
            try {
                SystemMonitor metrics = collectSystemMetrics();
                insertSystemMonitor(metrics);
                log.debug("系统监控数据收集完成");
            } catch (Exception e) {
                log.error("系统监控数据收集失败: {}", e.getMessage(), e);
            }
        }, 0, 1, TimeUnit.MINUTES);
        
        isMonitoring = true;
        log.info("系统监控已启动");
    }

    /**
     * 停止系统监控
     */
    @Override
    public void stopSystemMonitoring()
    {
        if (monitoringExecutor != null && !monitoringExecutor.isShutdown()) {
            monitoringExecutor.shutdown();
            try {
                if (!monitoringExecutor.awaitTermination(5, TimeUnit.SECONDS)) {
                    monitoringExecutor.shutdownNow();
                }
            } catch (InterruptedException e) {
                monitoringExecutor.shutdownNow();
                Thread.currentThread().interrupt();
            }
        }
        
        isMonitoring = false;
        log.info("系统监控已停止");
    }

    /**
     * 获取活跃连接数（简化实现）
     */
    private Integer getActiveConnectionCount()
    {
        // 这里应该通过系统命令或JMX获取实际的网络连接数
        // 简化实现，返回一个模拟值
        return (int) (Math.random() * 100) + 50;
    }
}