#region License

// Copyright (c) 2010, Jasper Yeh.
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without modification, 
// are permitted provided that the following conditions are met:
//
//    * Redistributions of source code must retain the above copyright notice, 
//      this list of conditions and the following disclaimer.
//    * Redistributions in binary form must reproduce the above copyright notice, 
//      this list of conditions and the following disclaimer in the documentation 
//      and/or other materials provided with the distribution.
//    * Neither the name of ClearCanvas Inc. nor the names of its contributors 
//      may be used to endorse or promote products derived from this software without 
//      specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 
// THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 
// PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR 
// CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 
// OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE 
// GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 
// HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 
// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 
// ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
// OF SUCH DAMAGE.

#endregion

using System;
using System.Diagnostics;
using System.IO;
using ClearCanvas.Common;

namespace Nullstack.ClearCanvasEx.DevTools.Common
{
    public class CCProcess
    {
        private const string _serviceProcessName = "ClearCanvas.Server.ShredHostService";
        private const string _desktopProcessName = "ClearCanvas.Desktop.Executable";

        private readonly Process _process;

        private CCProcess(Process process)
        {
            Platform.CheckForNullReference(process, "process");
            Platform.CheckFalse(process.HasExited, "Process cannot have exited already.");

            _process = process;
        }

        public string Name
        {
            get { return _process.ProcessName; }
        }

        /// <summary>
        /// Gets the filename of the process' entry module.
        /// </summary>
        public string Filename
        {
            get { return _process.MainModule.FileName; }
        }

        /// <summary>
        /// Gets the process ID.
        /// </summary>
        public int ProcessId
        {
            get { return _process.Id; }
        }

        /// <summary>
        /// Gets the working directory of the process.
        /// </summary>
        public string WorkingDirectory
        {
            get
            {
                if (_process.HasExited)
                    return string.Empty;

                try
                {
                    return Path.GetDirectoryName(_process.MainModule.FileName);
                }
                catch (Exception)
                {
                    return string.Empty;
                }
            }
        }

        public override string ToString()
        {
            return _process.ProcessName;
        }

        public static implicit operator Process(CCProcess process)
        {
            return process._process;
        }

        #region Static Helpers

        public static CCProcess GetDesktopProcess()
        {
            return FindProcess(_desktopProcessName);
        }

        public static CCProcess GetServiceProcess()
        {
            return FindProcess(_serviceProcessName);
        }

        private static CCProcess FindProcess(string processName)
        {
            var pathCurDir = new CCPath(Process.GetCurrentProcess().MainModule.FileName.ToLowerInvariant().Replace(Path.DirectorySeparatorChar, '/'));
            var score = 0;
            Process targetProcess = null;
            foreach (var process in Process.GetProcessesByName(processName))
            {
                try
                {
                    var processDir = Path.GetDirectoryName(process.MainModule.FileName);
                    if (string.IsNullOrEmpty(processDir))
                        continue;

                    var pathProcessDir = new CCPath(processDir.ToLowerInvariant().Replace(Path.DirectorySeparatorChar, '/'));
                    var scoreProcessDir = pathCurDir.GetCommonPath(pathProcessDir).Segments.Count;
                    if (scoreProcessDir > score)
                    {
                        score = scoreProcessDir;
                        targetProcess = process;
                    }
                }
                catch (Exception)
                {
                    // shrug
                }
            }
            return targetProcess != null ? new CCProcess(targetProcess) : null;
        }

        #endregion
    }
}