using mdfinder.hashprovider;
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.IO;
using System.IO.Compression;
using System.Linq;
using System.Reflection;
using System.Threading;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Forms;
using System.Windows.Media.Imaging;

namespace mdfinder
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        /// <summary> The media extentions. </summary>
        private static readonly string[] MEDIA_EXTENTIONS = new[] { ".AVI", ".MPG", ".MPEG", ".MP3", ".MP4", ".MKV", ".WAV" };

        /// <summary> The image extentions. </summary>
        private static readonly string[] IMAGE_EXTENTIONS = new[] { ".JPG", ".JPEG", ".PNG", ".BMP", ".TIF", ".TIFF", ".ICO", "GIF" };

        /// <summary> The text extentions. </summary>
        private static readonly string[] TEXT_EXTENTIONS = new[] { ".TXT", ".XML", ".HTM", ".HTML", ".JS", ".CSS" };

        #region Properties

        /// <summary> Gets or sets the database. </summary>
        /// <value> The database. </value>
        public DBHelper Database { get; set; }

        /// <summary> Gets or sets the scanner. </summary>
        /// <value> The scanner. </value>
        public Scanner Scanner { get; set; }

        /// <summary> Gets or sets the hash providers. </summary>
        /// <value> The hash providers. </value>
        public IEnumerable<IHashProvider> HashProviders { get; set; }

        /// <summary> Gets or sets the default provider. </summary>
        /// <value> The default provider. </value>
        public IHashProvider DefaultProvider { get; set; }

        /// <summary> Gets or sets the scan results. </summary>
        /// <value> The scan results. </value>
        public ScanResults ScanResults { get; set; }

        #endregion Properties

        #region Constructors

        /// <summary> Default constructor for the main window of the application. </summary>
        public MainWindow()
        {
            this.Database = new DBHelper();
            this.Scanner = new Scanner();
            this.DefaultProvider = new MD5HashProvider();
            this.HashProviders = GetProviderPlugins();
            this.ScanResults = new ScanResults();

            this.Scanner.DirectoryFound += (sender, args) => Dispatcher.Invoke(() => txtProgressLabel.Content = args.Directory.Name);
            this.Scanner.FilesFound += (sender, args) =>
            {
                foreach(var file in args.Files)
                {
                    if(Properties.Settings.Default.SkipEmptyFiles && file.Length == 0)
                    {
                        break;
                    }

                    var provider = this.HashProviders.Where(hp => hp.FileExtensions.Contains(file.Extension.ToUpper())).OrderByDescending(hp => hp.Priority).FirstOr(this.DefaultProvider);
                    this.Database.InsertFileRecord(file.FullName, file.Length, provider.GetHash(file), provider.Name);
                    Dispatcher.Invoke(() => txtProgressLabel.Content = file.FullName);
                }
            };
            this.Scanner.ReportProgress += (sender, args) => Dispatcher.Invoke(() =>
            {
                if(args.Processed > 0)
                {
                    this.progressBar.Value = args.Percentage * 100;
                    this.taskBarInfo.ProgressValue = args.Percentage;
                }
                else
                {
                    this.taskBarInfo.ProgressState = System.Windows.Shell.TaskbarItemProgressState.None;
                }
            });

            InitializeComponent();
        }

        #endregion Constructors

        #region Methods

        /// <summary> Gets the provider plugins from a folder. </summary>
        /// <returns>
        /// An enumerator that allows foreach to be used to process the provider plugins in this
        /// collection.
        /// </returns>
        private IEnumerable<IHashProvider> GetProviderPlugins()
        {
            if(!string.IsNullOrWhiteSpace(Properties.Settings.Default.ProviderFolder) && Directory.Exists(Properties.Settings.Default.ProviderFolder))
            {
                var directory = new DirectoryInfo(Properties.Settings.Default.ProviderFolder);
                foreach(var pluginFile in directory.GetFiles("*.dll"))
                {
                    var assembly = Assembly.LoadFrom(pluginFile.FullName);
                    foreach(var type in assembly.GetTypes().Where(t => t.GetInterface("IHashProvider") != null))
                    {
                        yield return Activator.CreateInstance(type) as IHashProvider;
                    }
                }
            }
        }

        /// <summary> Sets duplicate file collection. </summary>
        /// <param name="duplicates"> The duplicates. </param>
        private void SetDuplicateFileCollection(IEnumerable<DuplicateFileGroup> duplicates)
        {
            this.ScanResults.DuplicateFiles = duplicates;
        }

        /// <summary> Gets the duplicate files in this collection. </summary>
        /// <returns>
        /// An enumerator that allows foreach to be used to process the duplicate files in this
        /// collection.
        /// </returns>
        private IEnumerable<DuplicateFileGroup> GetDuplicateFiles()
        {
            return this.Database.GetFileRecords().GroupBy(fr => fr.Hash).Where(g => g.Count() > 1).Select(g => new DuplicateFileGroup(g)).ToArray();
        }

        /// <summary> Resets the media preview. </summary>
        private void ResetMediaPreview()
        {
            this.mediaPreview.Stop();

            this.mediaPreview.Source = null;
            this.imagePanel.RowDefinitions.Clear();
            this.imagePanel.Children.Clear();
            this.textPreview.Text = string.Empty;

            this.mediaPreviewContainer.Visibility = Visibility.Hidden;
            this.imagePanel.Visibility = Visibility.Hidden;
            this.textPreview.Visibility = Visibility.Hidden;
            this.stackNoPreview.Visibility = Visibility.Visible;
        }

        private void ProcessDuplicateFileGroups(string tag, bool archive, params DuplicateFileGroup[] duplicateFileGroups)
        {
            new Thread(() =>
            {
                var actionableFiles = Enumerable.Empty<FileRecord>();
                var archiveName = string.Format("archive-{0}.zip", DateTime.Now.ToString("yyyy-MM-dd-HH-mm-ss"));

                this.Dispatcher.Invoke(() => this.IsEnabled = false);

                if(duplicateFileGroups.Any())
                {
                    foreach(var duplicateFileGroup in duplicateFileGroups)
                    {
                        if(duplicateFileGroup != null)
                        {
                            if(tag == "largest")
                            {
                                actionableFiles = duplicateFileGroup.FileRecords.OrderByDescending(fr => fr.Size).Skip(1);
                            }
                            else if(tag == "smallest")
                            {
                                actionableFiles = duplicateFileGroup.FileRecords.OrderBy(fr => fr.Size).Skip(1);
                            }
                            else
                            {
                                actionableFiles = duplicateFileGroup.FileRecords.Where(fr => !fr.Keep);
                            }

                            ZipArchive zipFile = null;

                            if(archive)
                            {
                                if(duplicateFileGroups.Count() == 1)
                                {
                                    archiveName = string.Format("{0}.zip", duplicateFileGroup.Hash);
                                }

                                zipFile = ZipFile.Open(System.IO.Path.Combine(Properties.Settings.Default.ArchiveFolder, archiveName), ZipArchiveMode.Update);
                            }

                            if(archive && zipFile != null)
                            {
                                //Zip everything up.
                                foreach(var file in actionableFiles)
                                {
                                    zipFile.CreateEntryFromFile(file.Path.LocalPath, System.IO.Path.GetFileName(file.Path.LocalPath));
                                }
                                zipFile.Dispose();
                            }

                            // Make sure the garbage collector has enough time to clear up all
                            // references to the files.
                            GC.Collect();
                            GC.WaitForPendingFinalizers();

                            foreach(var file in actionableFiles)
                            {
                                //Do the deletion
                                try
                                {
                                    File.Delete(file.Path.LocalPath);
                                    this.Database.RemoveFileRecord(file.Id);
                                }
                                catch(Exception ex)
                                {
                                    var r = System.Windows.MessageBox.Show(ex.Message, string.Format("Error deleting {0}", file.Path));
                                }
                            }

                            SetDuplicateFileCollection(GetDuplicateFiles());
                        }
                    }
                }

                this.Dispatcher.Invoke(() => this.IsEnabled = true);
            }).Start();
        }

        /// <summary> Event handler. Called by btnFilePicker for click events. </summary>
        /// <param name="sender"> Source of the event. </param>
        /// <param name="e">      Routed event information. </param>
        private void btnFilePicker_Click(object sender, RoutedEventArgs e)
        {
            var fbd = new FolderBrowserDialog();

            if(fbd.ShowDialog() == System.Windows.Forms.DialogResult.OK)
            {
                txtScanLocation.Text = fbd.SelectedPath;
            }
        }

        /// <summary> Event handler. Called by btnScan for click events. </summary>
        /// <param name="sender"> Source of the event. </param>
        /// <param name="e">      Routed event information. </param>
        private void btnScan_Click(object sender, RoutedEventArgs e)
        {
            var location = txtScanLocation.Text;
            ResetMediaPreview();
            if(!this.Scanner.IsScanning)
            {
                new Thread(() =>
                {
                    this.Scanner.Scan(location);
                    this.Dispatcher.Invoke(() => txtProgressLabel.Content = string.Empty);
                    this.Dispatcher.Invoke(() => progressBar.Value = 0);
                    this.Dispatcher.Invoke(() => taskBarInfo.ProgressState = System.Windows.Shell.TaskbarItemProgressState.Normal);
                    this.Dispatcher.Invoke(() => taskBarInfo.ProgressValue = 0);
                    this.Dispatcher.Invoke(() => SetDuplicateFileCollection(GetDuplicateFiles()));
                }).Start();
            }
        }

        /// <summary> Event handler. Called by BtnClear for click events. </summary>
        /// <param name="sender"> Source of the event. </param>
        /// <param name="e">      Routed event information. </param>
        private void BtnClear_Click(object sender, RoutedEventArgs e)
        {
            this.Database.Clear();
            ResetMediaPreview();
            SetDuplicateFileCollection(Enumerable.Empty<DuplicateFileGroup>());
        }

        private void BtnNotDuplicate_Click(object sender, RoutedEventArgs e)
        {
            if(this.ScanResults.SelectedDuplicateFileGroup != null)
            {
                foreach(var fileRecord in this.ScanResults.SelectedDuplicateFileGroup.FileRecords)
                {
                    this.Database.RemoveFileRecord(fileRecord.Id);
                }
                ResetMediaPreview();
                this.ScanResults.DuplicateFiles = this.ScanResults.DuplicateFiles.Except(new[] { this.ScanResults.SelectedDuplicateFileGroup });
                this.ScanResults.SelectedDuplicateFileGroup = null;
            }
        }

        /// <summary> Event handler. Called by Hyperlink for click events. </summary>
        /// <param name="sender"> Source of the event. </param>
        /// <param name="e">      Routed event information. </param>
        private void Hyperlink_Click(object sender, RoutedEventArgs e)
        {
            Hyperlink link = (Hyperlink)e.OriginalSource;
            Process.Start(link.NavigateUri.AbsoluteUri);
        }

        /// <summary> Event handler. Called by MenuOptions for click events. </summary>
        /// <param name="sender"> Source of the event. </param>
        /// <param name="e">      Routed event information. </param>
        private void MenuOptions_Click(object sender, RoutedEventArgs e)
        {
            var optionsWindow = new OptionsWindow();

            optionsWindow.ShowDialog();

            this.HashProviders = GetProviderPlugins();
        }

        /// <summary> Event handler. Called by MenuAbout for click events. </summary>
        /// <param name="sender"> Source of the event. </param>
        /// <param name="e">      Routed event information. </param>
        private void MenuAbout_Click(object sender, RoutedEventArgs e)
        {
            var aboutWindow = new AboutWindow();

            aboutWindow.Show();
        }

        /// <summary> Event handler. Called by ListBoxDupes for initialized events. </summary>
        /// <param name="sender"> Source of the event. </param>
        /// <param name="e">      Event information. </param>
        private void ListBoxDupes_Initialized(object sender, EventArgs e)
        {
            new Thread(() =>
            {
                this.Dispatcher.Invoke(() => SetDuplicateFileCollection(GetDuplicateFiles()));
            }).Start();
        }

        /// <summary> Event handler. Called by ListBoxDupes for selection changed events. </summary>
        /// <param name="sender"> Source of the event. </param>
        /// <param name="e">      Selection changed event information. </param>
        private void ListBoxDupes_SelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            if(e.AddedItems.Count > 0)
            {
                this.mediaPreview.Source = null;
                this.imagePanel.Children.Clear();
                this.imagePanel.RowDefinitions.Clear();
                this.textPreview.Text = string.Empty;

                var rowCount = 0;
                var selectedGroup = e.AddedItems[0] as DuplicateFileGroup;

                if(selectedGroup.FileRecords.All(f => IMAGE_EXTENTIONS.Contains(System.IO.Path.GetExtension(f.Path.LocalPath).ToUpper())))
                {
                    this.SingleFileGroupDuplicateActions.Visibility = Visibility.Hidden;
                    this.AllFileGroupsDuplicateActions.Visibility = Visibility.Visible;

                    for(int i = 0; i < selectedGroup.FileRecords.Count; i++)
                    {
                        var rowDefinition = new RowDefinition();
                        rowDefinition.Height = new GridLength(1, GridUnitType.Star);
                        this.imagePanel.RowDefinitions.Add(rowDefinition);
                    }

                    foreach(var item in selectedGroup.FileRecords)
                    {
                        var fileRecord = item as FileRecord;

                        var extension = System.IO.Path.GetExtension(fileRecord.Path.LocalPath).ToUpper();
                        if(IMAGE_EXTENTIONS.Contains(extension))
                        {
                            this.mediaPreview.Source = null;
                            var image = new Image();
                            image.Source = new BitmapImage(fileRecord.Path);
                            this.imagePanel.Children.Add(image);
                            Grid.SetRow(image, rowCount++);
                            this.textPreview.Text = string.Empty;

                            this.mediaPreviewContainer.Visibility = Visibility.Hidden;
                            this.imagePanel.Visibility = Visibility.Visible;
                            this.textPreview.Visibility = Visibility.Hidden;
                            this.stackNoPreview.Visibility = Visibility.Hidden;
                        }
                        else if(TEXT_EXTENTIONS.Contains(extension))
                        {
                            this.mediaPreview.Source = null;
                            this.imagePanel.Children.Clear();
                            this.imagePanel.RowDefinitions.Clear();
                            this.textPreview.Text = File.ReadAllText(fileRecord.Path.LocalPath);

                            this.mediaPreviewContainer.Visibility = Visibility.Hidden;
                            this.imagePanel.Visibility = Visibility.Hidden;
                            this.textPreview.Visibility = Visibility.Visible;
                            this.stackNoPreview.Visibility = Visibility.Hidden;
                        }
                    }

                    this.ScanResults.SelectedDuplicateFileGroup = selectedGroup;
                }
                else
                {
                    this.ScanResults.SelectedDuplicateFileGroup = e.AddedItems[0] as DuplicateFileGroup;
                }
            }
            else
            {
                this.ScanResults.SelectedDuplicateFileGroup = null;
            }
        }

        /// <summary> Event handler. Called by PerformDuplicateAction for click events. </summary>
        /// <param name="sender"> Source of the event. </param>
        /// <param name="e">      Routed event information. </param>
        private void PerformDuplicateAction_Click(object sender, RoutedEventArgs e)
        {
            var tag = (sender as System.Windows.Controls.Button).Tag.ToString();
            var duplicateFileGroup = this.listBoxDupes.SelectedItem as DuplicateFileGroup;
            var archive = this.checkboxArchiveRemainingFiles.IsChecked ?? false;

            this.ScanResults.SelectedDuplicateFileGroup = null;

            ResetMediaPreview();

            ProcessDuplicateFileGroups(tag, archive, duplicateFileGroup);
        }

        private void PerformDuplicateActionAll_Click(object sender, RoutedEventArgs e)
        {
            var tag = (sender as System.Windows.Controls.Button).Tag.ToString();
            var duplicateFileGroups = new List<DuplicateFileGroup>();
            var archive = this.checkboxArchiveRemainingFiles.IsChecked ?? false;

            foreach(var item in this.listBoxDupes.Items)
            {
                duplicateFileGroups.Add(item as DuplicateFileGroup);
            }

            this.ScanResults.SelectedDuplicateFileGroup = null;

            ResetMediaPreview();

            ProcessDuplicateFileGroups(tag, archive, duplicateFileGroups.ToArray());
        }

        /// <summary>
        /// Event handler. Called by DatagridFileList for selection changed events.
        /// </summary>
        /// <param name="sender"> Source of the event. </param>
        /// <param name="e">      Selection changed event information. </param>
        private void DatagridFileList_SelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            if(e.AddedItems.Count == 1)
            {
                var fileRecord = e.AddedItems[0] as FileRecord;

                if(fileRecord != null)
                {
                    this.SingleFileGroupDuplicateActions.Visibility = Visibility.Visible;
                    this.AllFileGroupsDuplicateActions.Visibility = Visibility.Hidden;

                    var extension = System.IO.Path.GetExtension(fileRecord.Path.LocalPath).ToUpper();

                    if(MEDIA_EXTENTIONS.Contains(extension))
                    {
                        this.mediaPreview.Source = fileRecord.Path;
                        this.imagePanel.Children.Clear();
                        this.imagePanel.RowDefinitions.Clear();
                        this.textPreview.Text = string.Empty;

                        this.mediaPreviewContainer.Visibility = Visibility.Visible;
                        this.imagePanel.Visibility = Visibility.Hidden;
                        this.textPreview.Visibility = Visibility.Hidden;
                        this.stackNoPreview.Visibility = Visibility.Hidden;
                    }
                    else if(IMAGE_EXTENTIONS.Contains(extension))
                    {
                        var rowDefinition = new RowDefinition();
                        rowDefinition.Height = new GridLength(1, GridUnitType.Star);
                        var image = new Image();
                        image.Source = new BitmapImage(fileRecord.Path);
                        Grid.SetRow(image, 0);

                        this.mediaPreview.Source = null;
                        this.imagePanel.Children.Clear();
                        this.imagePanel.RowDefinitions.Clear();
                        this.imagePanel.RowDefinitions.Add(rowDefinition);
                        this.imagePanel.Children.Add(image);
                        this.textPreview.Text = string.Empty;

                        this.mediaPreviewContainer.Visibility = Visibility.Hidden;
                        this.imagePanel.Visibility = Visibility.Visible;
                        this.textPreview.Visibility = Visibility.Hidden;
                        this.stackNoPreview.Visibility = Visibility.Hidden;
                    }
                    else if(TEXT_EXTENTIONS.Contains(extension))
                    {
                        this.mediaPreview.Source = null;
                        this.imagePanel.Children.Clear();
                        this.imagePanel.RowDefinitions.Clear();
                        this.textPreview.Text = File.ReadAllText(fileRecord.Path.LocalPath);

                        this.mediaPreviewContainer.Visibility = Visibility.Hidden;
                        this.imagePanel.Visibility = Visibility.Hidden;
                        this.textPreview.Visibility = Visibility.Visible;
                        this.stackNoPreview.Visibility = Visibility.Hidden;
                    }
                    else //Can't preivew.
                    {
                        ResetMediaPreview();
                    }
                }
            }
        }
    }

    #endregion Methods
}