using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using System.Collections.ObjectModel;
using System.IO;
using XML;
using TapeCatalog.Methods;
using System.Windows.Threading;



namespace TapeCatalog
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        private readonly ObservableCollection<FileEntry> _files = new ObservableCollection<FileEntry>();
        private DispatcherTimer _copySummaryTimer;

        // NOTE: FormatBytesToMb moved to Methods.SettingsUi; no local implementation kept.

        private void XmlFilesListBox_SelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            if (!(XmlFilesListBox.SelectedItem is string path))
            {
                XmlSummaryListView.Items.Clear();
                return;
            }

            try
            {
                if (!File.Exists(path))
                {
                    XmlSummaryListView.Items.Clear();
                    return;
                }

                var doc = System.Xml.Linq.XDocument.Load(path);
                var root = doc.Root;
                if (root == null)
                {
                    XmlSummaryListView.Items.Clear();
                    return;
                }

                XmlSummaryListView.Items.Clear();

                if (string.Equals(root.Name.LocalName, "Files", StringComparison.OrdinalIgnoreCase))
                {
                    foreach (var fe in root.Elements("File"))
                    {
                        var fn = fe.Element("Filename")?.Value ?? string.Empty;
                        var fd = fe.Element("FileDir")?.Value ?? string.Empty;
                        var st = fe.Element("Status")?.Value ?? string.Empty;
                        XmlSummaryListView.Items.Add(new FileEntry { Filename = fn, FileDir = fd, Status = st });
                    }
                }
                else if (string.Equals(root.Name.LocalName, "TapeEntries", StringComparison.OrdinalIgnoreCase))
                {
                    foreach (var entry in root.Elements("Entry"))
                    {
                        var fn = entry.Element("Filename")?.Value ?? string.Empty;
                        var med = entry.Element("Medium")?.Value ?? string.Empty;
                        var mod = entry.Element("Modified")?.Value ?? string.Empty;
                        XmlSummaryListView.Items.Add(new FileEntry { Filename = fn, FileDir = med, Status = mod });
                    }
                }
                else
                {
                    // Unknown format - show nothing
                }
            }
            catch
            {
                XmlSummaryListView.Items.Clear();
            }
        }

        public MainWindow()
        {
            InitializeComponent();
            FilesListView.ItemsSource = _files;
            // start periodic update of copy summary
            _copySummaryTimer = new DispatcherTimer { Interval = TimeSpan.FromMilliseconds(500) };
            _copySummaryTimer.Tick += (s, e) => UpdateCopySummary();
            _copySummaryTimer.Start();
        }
        #region (export Medium)
        private void EXPORT_MEDIUM(object sender, RoutedEventArgs e)
        {
            var selected = MediumComboBox.SelectedItem as string;
            if (string.IsNullOrWhiteSpace(selected))
            {
                MessageBox.Show(this, "Bitte ein Medium im Dropdown auswählen.", "Keine Auswahl", MessageBoxButton.OK, MessageBoxImage.Warning);
                return;
            }

            // collect matching entries from TapeCatalogListView
            var matches = new List<XML.Methods.TapeEntry>();
            foreach (var item in TapeCatalogListView.Items)
            {
                var te = item as dynamic;
                if (te == null) continue;
                string m = te.Medium as string;
                if (string.Equals(m, selected, StringComparison.OrdinalIgnoreCase))
                {
                    matches.Add(new XML.Methods.TapeEntry { Medium = te.Medium, Filename = te.Filename, Modified = te.Modified });
                }
            }

            if (matches.Count == 0)
            {
                MessageBox.Show(this, "Keine Einträge für das gewählte Medium gefunden.", "Keine Einträge", MessageBoxButton.OK, MessageBoxImage.Information);
                return;
            }

            // delegate export to XML helper
            XML.Methods.ExportTapeEntries(this, selected, matches);
        }
        #endregion
        #region (Import List)
        private void IMPORT_LIST(object sender, RoutedEventArgs e)
        {
            // delegate to XML import helper
            XML.Methods.ImportList(this, _files, SourceTextBox, ArchiveTextBox);
        }
        #endregion (Import List)
        #region (COPY_TO_TAPECATALOG)
        private void COPY_TO_TAPECATALOG(object sender, RoutedEventArgs e)
        {
            // Only copy entries where the verification status indicates OK (checked)
            try
            {
                var okEntries = _files.Where(f => string.Equals(f.Status, "✔", StringComparison.Ordinal)).ToList();
                if (okEntries.Count == 0)
                {
                    MessageBox.Show(this, "No verified entries to copy to TapeCatalog.", "Nothing to copy", MessageBoxButton.OK, MessageBoxImage.Information);
                    return;
                }

                XML.Methods.CopyToTapeCatalog(this, okEntries, TapeCatalogListView);
            }
            catch (Exception ex)
            {
                MessageBox.Show(this, $"Error copying to TapeCatalog: {ex.Message}", "Error", MessageBoxButton.OK, MessageBoxImage.Error);
            }
        }
        #endregion (COPY_TO_TAPECATALOG)
        #region (COPY_FROM_SRCARC)
        private void COPY_FROM_SRCARC(object sender, RoutedEventArgs e)
        {
            XML.Methods.CopyToTapeCatalog(this, _files, TapeCatalogListView);
        }
        #endregion (COPY_FROM_SRCARC)
        #region (REFRESH_MEDIUMS)
        private void REFRESH_MEDIUMS(object sender, RoutedEventArgs e)
        {
            // collect distinct mediums from TapeCatalogListView items
            try
            {
                var mediums = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
                foreach (var item in TapeCatalogListView.Items)
                {
                    var te = item as dynamic;
                    if (te == null) continue;
                    string m = te.Medium as string;
                    if (!string.IsNullOrWhiteSpace(m)) mediums.Add(m);
                }

                MediumComboBox.ItemsSource = mediums.OrderBy(s => s).ToList();
            }
            catch (Exception ex)
            {
                MessageBox.Show(this, $"Fehler beim Aktualisieren der Medium-Liste: {ex.Message}", "Fehler", MessageBoxButton.OK, MessageBoxImage.Error);
            }
        }
        #endregion (REFRESH_MEDIUMS)
        #region (EXPORT_LIST)
        private void EXPORT_LIST(object sender, RoutedEventArgs e)
        {
            // Delegate export to XML helper
            XML.Methods.ExportList(this, SourceTextBox.Text, ArchiveTextBox.Text, _files);
        }

        private void SET_RES_DIR(object sender, RoutedEventArgs e)
        {
            var sel = SettingsUi.SelectDirectory("Select Source folder");
            if (!string.IsNullOrWhiteSpace(sel)) SourceTextBox.Text = sel;
        }
        #endregion (EXPORT_LIST)
        #region (SET_ARC_DIR)
        private void SET_ARC_DIR(object sender, RoutedEventArgs e)
        {
            var sel = SettingsUi.SelectDirectory("Select Archive folder");
            if (!string.IsNullOrWhiteSpace(sel)) ArchiveTextBox.Text = sel;
        }
        #endregion (SET_ARC_DIR)
        #region (SET_XML_DIR)
        private void SET_XML_DIR(object sender, RoutedEventArgs e)
        {
            var sel = SettingsUi.SelectDirectory("Select XML folder");
            if (!string.IsNullOrWhiteSpace(sel)) XmlDirectoryTextBox.Text = sel;
        }
        #endregion (SET_XML_DIR)

        #region (LOAD_XML_FILES)
        private void LOAD_XML_FILES(object sender, RoutedEventArgs e)
        {
            var xmlPath = XmlDirectoryTextBox.Text?.Trim();
            if (string.IsNullOrWhiteSpace(xmlPath) || !Directory.Exists(xmlPath))
            {
                MessageBox.Show(this, "Please select a valid XML directory first.", "Invalid XML Directory", MessageBoxButton.OK, MessageBoxImage.Warning);
                return;
            }

            string[] files;
            try
            {
                files = Directory.GetFiles(xmlPath, "*.xml", SearchOption.TopDirectoryOnly);
            }
            catch (Exception ex)
            {
                MessageBox.Show(this, $"Error enumerating XML files: {ex.Message}", "Error", MessageBoxButton.OK, MessageBoxImage.Error);
                return;
            }

            XmlFilesListBox.Items.Clear();
            XmlSummaryListView.Items.Clear();
            foreach (var f in files)
            {
                XmlFilesListBox.Items.Add(f);
            }

            // switch to XML tab
            foreach (var it in MainTabControl.Items)
            {
                if (it is TabItem ti && (ti.Header as string) == "XML")
                {
                    MainTabControl.SelectedItem = ti;
                    break;
                }
            }
        }
        #endregion (LOAD_XML_FILES)
        #region (SCAN_RES_DIR)
        private void SCAN_RES_DIR(object sender, RoutedEventArgs e)
        {
            var path = SourceTextBox.Text?.Trim();
            if (string.IsNullOrWhiteSpace(path) || !Directory.Exists(path))
            {
                MessageBox.Show("Please select a valid Source directory first.", "No directory", MessageBoxButton.OK, MessageBoxImage.Warning);
                return;
            }

            try
            {
                var count = SettingsUi.ScanSource(path, _files);
                MessageBox.Show($"Scan abgeschlossen. Einträge: {count}", "Scan beendet", MessageBoxButton.OK, MessageBoxImage.Information);
            }
            catch (Exception ex)
            {
                MessageBox.Show($"Error scanning directory: {ex.Message}", "Error", MessageBoxButton.OK, MessageBoxImage.Error);
            }
        }
        #endregion (SCAN_RES_DIR)
        #region(SCAN_ARC_DIR)
        private void SCAN_ARC_DIR(object sender, RoutedEventArgs e)
        {
            var path = ArchiveTextBox.Text?.Trim();
            if (string.IsNullOrWhiteSpace(path) || !Directory.Exists(path))
            {
                MessageBox.Show("Please select a valid Archive directory first.", "No directory", MessageBoxButton.OK, MessageBoxImage.Warning);
                return;
            }

            try
            {
                var count = SettingsUi.ScanArchive(path, _files);
                MessageBox.Show($"Scan abgeschlossen. Einträge: {count}", "Scan beendet", MessageBoxButton.OK, MessageBoxImage.Information);
            }
            catch (Exception ex)
            {
                MessageBox.Show($"Error scanning archive directory: {ex.Message}", "Error", MessageBoxButton.OK, MessageBoxImage.Error);
            }
        }
        #endregion(SCAN_ARC_DIR)
        #region (CLEAR_FILES)
        private void CLEAR_FILES(object sender, RoutedEventArgs e)
        {
            _files.Clear();
        }
        #endregion (CLEAR_FILES)
        #region (VERIFY_SIZES)
        private void VERIFY_SIZES(object sender, RoutedEventArgs e)
        {
            // determine archive drive name (volume label or drive root)
            string archivePath = ArchiveTextBox.Text?.Trim();
            string archiveDriveName = string.Empty;
            if (!string.IsNullOrWhiteSpace(archivePath))
            {
                try
                {
                    var root = System.IO.Path.GetPathRoot(archivePath);
                    if (!string.IsNullOrWhiteSpace(root))
                    {
                        try
                        {
                            var di = new DriveInfo(root);
                            archiveDriveName = string.IsNullOrWhiteSpace(di.VolumeLabel) ? root.TrimEnd('\\') : di.VolumeLabel;
                        }
                        catch
                        {
                            archiveDriveName = root.TrimEnd('\\');
                        }
                    }
                }
                catch
                {
                    archiveDriveName = string.Empty;
                }
            }

            foreach (var entry in _files)
            {
                // Sizes are stored in MB with two decimals; compare as doubles
                double src = 0;
                double arc = 0;
                double.TryParse(entry.SizeSrc, out src);
                double.TryParse(entry.SizeArc, out arc);

                if (src > 0 && arc > 0 && Math.Abs(src - arc) < 0.01)
                {
                    entry.Status = "✔";
                    entry.ArcDrive = archiveDriveName;
                }
                else
                {
                    entry.Status = "✖";
                    entry.ArcDrive = string.Empty;
                }
            }
        }

        // Populate CopyTreeView with directory structure from SourceTextBox
        private void POPULATE_COPY_TREE(object sender, RoutedEventArgs e)
        {
            Copy.PopulateTree(CopyTreeView, SourceTextBox.Text);
        }

        private void COPY_SELECTED_TO_ARCHIVE(object sender, RoutedEventArgs e)
        {
            var archivePath = ArchiveTextBox.Text?.Trim();
            if (string.IsNullOrWhiteSpace(archivePath) || !Directory.Exists(archivePath))
            {
                MessageBox.Show(this, "Please select a valid Archive directory first.", "Invalid Archive", MessageBoxButton.OK, MessageBoxImage.Warning);
                return;
            }

            var sourceRoot = SourceTextBox.Text?.Trim();
            if (string.IsNullOrWhiteSpace(sourceRoot) || !Directory.Exists(sourceRoot))
            {
                MessageBox.Show(this, "Please select a valid Source directory first.", "Invalid Source", MessageBoxButton.OK, MessageBoxImage.Warning);
                return;
            }

            var result = Copy.CopySelectedToArchive(CopyTreeView, sourceRoot, archivePath);
            MessageBox.Show(this, $"Copy finished. Success: {result.Item1}, Failed: {result.Item2}", "Copy completed", MessageBoxButton.OK, MessageBoxImage.Information);
        }

        private void UpdateCopySummary()
        {
            try
            {
                var files = Copy.GetCheckedFiles(CopyTreeView);
                CopySelectedCountText.Text = files.Count.ToString();

                double totalMb = 0;
                foreach (var f in files)
                {
                    try
                    {
                        var fi = new FileInfo(f);
                        totalMb += fi.Length / 1024.0 / 1024.0;
                    }
                    catch
                    {
                        // ignore
                    }
                }
                CopySelectedSizeText.Text = totalMb.ToString("F2");

                var archivePath = ArchiveTextBox.Text?.Trim();
                if (!string.IsNullOrWhiteSpace(archivePath))
                {
                    try
                    {
                        var root = System.IO.Path.GetPathRoot(archivePath);
                        if (!string.IsNullOrWhiteSpace(root))
                        {
                            var di = new DriveInfo(root);
                            // AvailableFreeSpace in bytes
                            double freeMb = di.AvailableFreeSpace / 1024.0 / 1024.0;
                            ArchiveFreeText.Text = freeMb.ToString("F2") + " MB";
                        }
                        else
                        {
                            ArchiveFreeText.Text = "N/A";
                        }
                    }
                    catch
                    {
                        ArchiveFreeText.Text = "N/A";
                    }
                }
                else
                {
                    ArchiveFreeText.Text = "N/A";
                }
            }
            catch (Exception)
            {
                // swallow periodic update errors; avoid UI disruptions
            }
        }
    }
    #endregion (VERIFY_SIZES)
    public class FileEntry : System.ComponentModel.INotifyPropertyChanged
    {
        public string Filename { get; set; }
        public string FileDir { get; set; }
        private string _sizeSrc;
        public string SizeSrc { get => _sizeSrc; set { _sizeSrc = value; OnPropertyChanged(nameof(SizeSrc)); } }
        private string _sizeArc;
        public string SizeArc { get => _sizeArc; set { _sizeArc = value; OnPropertyChanged(nameof(SizeArc)); } }
        public string ModSrc { get; set; }
        public string ModArc { get; set; }
        private string _status;
        public string Status { get => _status; set { _status = value; OnPropertyChanged(nameof(Status)); } }
        private string _arcDrive;
        public string ArcDrive { get => _arcDrive; set { _arcDrive = value; OnPropertyChanged(nameof(ArcDrive)); } }

        public event System.ComponentModel.PropertyChangedEventHandler PropertyChanged;
        private void OnPropertyChanged(string propName) => PropertyChanged?.Invoke(this, new System.ComponentModel.PropertyChangedEventArgs(propName));
    }
}