namespace Neovolve.Toolkit.TestSupport
{
    using System;
    using System.Diagnostics;
    using System.Diagnostics.CodeAnalysis;
    using System.Globalization;
    using System.IO;
    using System.Threading;
    
    /// <summary>
    /// The <see cref="IisExpress"/> class is used to manage an IIS Express instance for running integration tests.
    /// </summary>
    public class IisExpress : IDisposable
    {
        /// <summary>
        ///   Stores whether this instance has been disposed.
        /// </summary>
        private Boolean _isDisposed;
    
        /// <summary>
        ///   Stores the IIS Express process.
        /// </summary>
        private Process _process;
    
        /// <summary>
        /// Performs application-defined tasks associated with freeing, releasing, or resetting unmanaged resources.
        /// </summary>
        public void Dispose()
        {
            Dispose(true);
            GC.SuppressFinalize(this);
        }
    
        /// <summary>
        /// Starts IIS Express using the specified directory path and port.
        /// </summary>
        /// <param name="directoryPath">
        /// The directory path. 
        /// </param>
        /// <param name="port">
        /// The port. 
        /// </param>
        public void Start(String directoryPath, Int32 port)
        {
            String iisExpressPath = DetermineIisExpressPath();
            String arguments = String.Format(
                CultureInfo.InvariantCulture, "/path:\"{0}\" /port:{1}", directoryPath, port);
    
            ProcessStartInfo info = new ProcessStartInfo(iisExpressPath)
                                        {
                                            WindowStyle = ProcessWindowStyle.Hidden,
                                            ErrorDialog = true,
                                            LoadUserProfile = true,
                                            CreateNoWindow = false,
                                            UseShellExecute = false,
                                            Arguments = arguments
                                        };
    
            Thread startThread = new Thread(() => StartIisExpress(info))
                                        {
                                            IsBackground = true
                                        };
    
            startThread.Start();
        }
    
        /// <summary>
        /// Releases unmanaged and - optionally - managed resources.
        /// </summary>
        /// <param name="disposing">
        /// <c>true</c> to release both managed and unmanaged resources; <c>false</c> to release only unmanaged resources. 
        /// </param>
        protected virtual void Dispose(Boolean disposing)
        {
            if (_isDisposed)
            {
                return;
            }
    
            if (disposing)
            {
                // Free managed resources
                if (_process.HasExited == false)
                {
                    _process.CloseMainWindow();
                }
    
                _process.Dispose();
            }
    
            // Free native resources if there are any
            _isDisposed = true;
        }
    
        /// <summary>
        /// Determines the IIS express path.
        /// </summary>
        /// <returns>
        /// A <see cref="String"/> instance. 
        /// </returns>
        private static String DetermineIisExpressPath()
        {
            String iisExpressPath;
    
            if (Environment.Is64BitOperatingSystem)
            {
                iisExpressPath = Environment.GetFolderPath(Environment.SpecialFolder.ProgramFilesX86);
            }
            else
            {
                iisExpressPath = Environment.GetFolderPath(Environment.SpecialFolder.ProgramFiles);
            }
    
            iisExpressPath = Path.Combine(iisExpressPath, @"IIS Express\iisexpress.exe");
    
            return iisExpressPath;
        }
    
        /// <summary>
        /// Starts the IIS express.
        /// </summary>
        /// <param name="info">
        /// The info. 
        /// </param>
        [SuppressMessage("Microsoft.Design", "CA1031:DoNotCatchGeneralExceptionTypes",
            Justification = "Required here to ensure that the instance is disposed.")]
        private void StartIisExpress(ProcessStartInfo info)
        {
            try
            {
                _process = Process.Start(info);
    
                _process.WaitForExit();
            }
            catch (Exception)
            {
                Dispose();
            }
        }
    }
}