using System;
using System.IO;
using System.Security.Permissions;

namespace TestApp
{
    /**************************************************
     * Classe gestione verifica cambio files in directory
     * 
     * links:
     * https://docs.microsoft.com/it-it/dotnet/api/system.io.filesystemwatcher?view=netframework-4.0
     * https://www.c-sharpcorner.com/UploadFile/puranindia/filesystemwatcher-in-C-Sharp/
     * 
     * 
     * ***********************************************/
    public static class FSWatch
    {

        /// <summary>
        /// Metodo principale esecuzione check filesystem
        /// </summary>
        [PermissionSet(SecurityAction.Demand, Name = "FullTrust")]
        public static void Run()
        {
            //string[] args = Environment.GetCommandLineArgs();

            //// If a directory is not specified, exit program.
            //if (args.Length != 2)
            //{
            //    // Display the proper way to call the program.
            //    Console.WriteLine("Usage: Watcher.exe (directory)");
            //    return;
            //}

            try
            {
                // Create a new FileSystemWatcher and set its properties.
                using (FileSystemWatcher watcher = new FileSystemWatcher())
                {
                    //watcher.Path = args[1];

                    watcher.Path = Directory.GetCurrentDirectory();

                    // NO guardo le subdirs
                    watcher.IncludeSubdirectories = false;

                    // Watch for changes in LastAccess and LastWrite times, and
                    // the renaming of files or directories.
                    //watcher.NotifyFilter = NotifyFilters.DirectoryName
                    //                     | NotifyFilters.FileName
                    //                     | NotifyFilters.LastAccess
                    //                     | NotifyFilters.LastWrite
                    //                     | NotifyFilters.Size;
                    watcher.NotifyFilter = NotifyFilters.Attributes
                                         | NotifyFilters.CreationTime
                                         | NotifyFilters.DirectoryName
                                         | NotifyFilters.FileName
                                         | NotifyFilters.LastAccess
                                         | NotifyFilters.LastWrite
                                         | NotifyFilters.Security
                                         | NotifyFilters.Size;

                    // Only watch text files.
                    watcher.Filter = "*.*";

                    // Add event handlers.
                    watcher.Changed += OnChanged;
                    watcher.Created += OnChanged;
                    watcher.Error += OnError;
                    watcher.Deleted += OnChanged;
                    watcher.Renamed += OnRenamed;

                    // Begin watching.
                    watcher.EnableRaisingEvents = true;

                    // Wait for the user to quit the program.
                    Console.WriteLine("Press 'q' to quit the sample.");
                    while (Console.Read() != 'q') ;
                }
            }
            catch (IOException e)
            {
                //Console.WriteLine("A Exception Occurred :" + e);
                Utils.Log.Error("A Exception Occurred :" + e);
            }
            catch (Exception oe)
            {
                //Console.WriteLine("An Exception Occurred :" + oe);
                Utils.Log.Error("An Exception Occurred :" + oe);
            }
        }

        private static void OnError(object sender, ErrorEventArgs e) =>
            // Specify what is done when a file is changed, created, or deleted.
            Console.WriteLine($"{DateTime.Now} | Error: {e.GetException()}");

        // Define the event handlers.
        private static void OnChanged(object source, FileSystemEventArgs e) =>
            Utils.Log.Info($"File: {e.Name} {e.ChangeType}");
            // Specify what is done when a file is changed, created, or deleted.
            //Console.WriteLine($"{DateTime.Now} | File: {e.Name} {e.ChangeType} ({e.FullPath})");


        private static void OnRenamed(object source, RenamedEventArgs e) =>
            Utils.Log.Info($"File: {e.OldName} renamed to {e.Name}");
            // Specify what is done when a file is renamed.
            //Console.WriteLine($"{DateTime.Now} | File: {e.OldName} renamed to {e.Name} ({e.OldFullPath} --> {e.FullPath})");
    }
}