using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Diagnostics;
using System.Diagnostics.PerformanceData;
using System.Management;
using System.IO;
using System.Threading;
using System.Collections;

namespace ConsoleApplication1
{
    class Program
    {
        static string service = "JRUN";
        static string serviceName = "ColdFusion 8 Application Server";
        static bool jrunRunning = false;
        static bool jrunRestart = false;
        static int samplingInterval = 6000;        // 6 seconds
        static Queue qCPU = new Queue(30);
        static Queue qMEM = new Queue(30);
        static float cpuAvg = 0.0F;
        static float memAvg = 0.0F;
                
        static void Main(string[] args)
        {
            monitor(service, serviceName);
            Console.Read();
        }

        static void monitor(string service, string serviceName)
        {
            // infinite loop
            while (true)
            {
                jrunRunning = false; 
                // get the process as process list array
                Process[] processList = Process.GetProcessesByName(service);

                // if the process is avaialbe, then the process is running
                if (processList != null && processList.Length == 1)
                {
                    jrunRunning = true;
                }
                else
                {
                    // if the process has not been restarted then restart it
                    if (!jrunRestart)
                    {
                        jrunRestart = true;
                    }
                }

                // restart the process only if is not running and is not already started
                if (!jrunRunning && jrunRestart)
                {
                    jrunRestart = false;
                    qCPU.Clear();
                    qMEM.Clear();
                    cpuAvg = 0;
                    memAvg = 0;
                
                    try
                    {
                        // process is not running, STOP and START the process, and give a gap of 5 seconds between the processes
                        processStop(serviceName);
                        Thread.Sleep(5000);
                        processStart(serviceName);
                    }
                    catch (Exception ex)
                    {
                        // if any exception, restart the server again
                        jrunRestart = true;
                    }
                }

                if (jrunRunning)
                {
                    foreach (Process proc in processList)
                    {
                        // process specific CPU and Memory counters
                        PerformanceCounter cpu = new PerformanceCounter("Process", "% Processor Time", proc.ProcessName);
                        PerformanceCounter mem = new PerformanceCounter("Process", "Private Bytes", proc.ProcessName);

                        cpu.NextValue();
                        mem.NextValue();
                        System.Threading.Thread.Sleep(1000);
                        float fcpu = cpu.NextValue();
                        // sometimes, the cpu will be over 100% (Example 171.34%], if so set the value to a max of 100%
                        // to ensure a bad cpu data not to mess up the averages
                        if (fcpu > 100)
                        {
                            fcpu = 100;
                        }
                        float fmem = mem.NextValue() / 1024 / 1024;
                        Console.Write(proc.ProcessName + ": " + fcpu + "%" + " | " + fmem + "Mb | ");

                        // queue is used to store the latest 30 samples (only) for average calculation
                        // push to the queue (FIFO)
                        qCPU.Enqueue(fcpu);
                        qMEM.Enqueue(fmem);

                        if (qCPU.Count > 30)
                        {
                            // pop of the queue (FIFO)
                            qCPU.Dequeue();
                            qMEM.Dequeue();
                        }

                        // calculate the cpu average
                        cpuAvg = 0;
                        foreach (object obj in qCPU)
                        {
                            cpuAvg += (float)obj;
                            //Console.WriteLine("qCPU: " + obj);
                        }
                        cpuAvg = cpuAvg / qCPU.Count;
                        Console.Write("cpuAvg: " + cpuAvg + " | ");

                        // calculate the memeory average
                        memAvg = 0;
                        foreach (object obj in qMEM)
                        {
                            memAvg += (float)obj;
                            //Console.WriteLine("qMEM: " + obj);
                        }
                        memAvg = memAvg / qMEM.Count;
                        Console.Write("memAvg: " + memAvg + " | ");

                        Console.WriteLine("");

                    }

                    // if the cpu average exceeds 90% and memory average exceeds 1GB (hard coded here)
                    // restart Jrun instance
                    if (cpuAvg > 90 && memAvg > 1024)
                    {
                        //Console.WriteLine("cpuAvg: " + cpuAvg + " | memAvg: " + memAvg);
                        qCPU.Clear();
                        qMEM.Clear();
                        
                        // process is not running, STOP and START the process
                        processStop(serviceName);
                        Thread.Sleep(5000);
                        processStart(serviceName);
                    }
                }

                Thread.Sleep(samplingInterval - 1000);
            }
        }

        static void processStop(string serviceName)
        {
            // stop the process
            Console.WriteLine("stopping - " + serviceName);
            string cmd = "net stop \"" + serviceName + "\"";
            System.Diagnostics.ProcessStartInfo psi = new System.Diagnostics.ProcessStartInfo("CMD.exe", "/C " + cmd);
            psi.CreateNoWindow = true;
            psi.UseShellExecute = false;
            System.Diagnostics.Process p = System.Diagnostics.Process.Start(psi);
            p.WaitForExit(30000);           //wait for 30 sec
            int exitCode = p.ExitCode;
            Console.WriteLine("exitCode: " + exitCode);
            Console.WriteLine("stopped - " + serviceName);
            p.Close();
        }

        static void processStart(string serviceName)
        {
            // start the process
            Console.WriteLine("starting - " + serviceName);
            string cmd = "net start \"" + serviceName + "\"";
            System.Diagnostics.ProcessStartInfo psi = new System.Diagnostics.ProcessStartInfo("CMD.exe", "/C " + cmd);
            psi.CreateNoWindow = true;
            psi.UseShellExecute = false;
            System.Diagnostics.Process p = System.Diagnostics.Process.Start(psi);
            p.WaitForExit(30000);           //wait for 30 sec
            int exitCode = p.ExitCode;
            Console.WriteLine("exitCode: " + exitCode);
            Console.WriteLine("started - " + serviceName);
            p.Close();
        }

        static void TESTJRunRestart2()
        {
            Process myProcess = new Process();
            ProcessStartInfo myProcessStartInfo = new ProcessStartInfo("C:\\ColdFusion8\\runtime\\bin\\jrun.exe");
            //ProcessStartInfo myProcessStartInfo = new ProcessStartInfo("C:\\ColdFusion8\\runtime\\bin\\jrunsvc.exe","-start");
            myProcessStartInfo.UseShellExecute = false;
            myProcessStartInfo.WindowStyle = ProcessWindowStyle.Minimized;
            myProcessStartInfo.Arguments = "-start";
            //ProcessStartInfo.RedirectStandardOutput = true;
            myProcess.StartInfo = myProcessStartInfo;
            myProcess.Start();

            Console.WriteLine("started 2");
            myProcess.Close();

        }
    }
}