using System.Collections.ObjectModel;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Input;
using VideoDownloader.Browser;

namespace VideoDownloader.App;

/// <summary>UC-K16 즐겨찾기 관리 창 — 검색·편집(M17)·삭제·HTML 내보내기/가져오기(M19).</summary>
public partial class BookmarkManagerWindow : Window
{
    private readonly ObservableCollection<Bookmark> _source;
    private readonly Action _persist;

    public BookmarkManagerWindow(ObservableCollection<Bookmark> bookmarks, Action persist)
    {
        InitializeComponent();
        _source = bookmarks;
        _persist = persist;
        List.ItemsSource = _source;
    }

    private void SearchBox_TextChanged(object sender, TextChangedEventArgs e)
    {
        var q = SearchBox.Text?.Trim() ?? "";
        var view = System.Windows.Data.CollectionViewSource.GetDefaultView(_source);
        view.Filter = q.Length == 0
            ? null
            : o => o is Bookmark b &&
                   (b.Title.Contains(q, StringComparison.OrdinalIgnoreCase) ||
                    b.Url.Contains(q, StringComparison.OrdinalIgnoreCase));
    }

    private void Edit_Click(object sender, RoutedEventArgs e)
    {
        if ((sender as FrameworkElement)?.DataContext is not Bookmark b) return;
        var title = InputBox("즐겨찾기 편집", "이름", b.Title);
        if (title == null) return;
        var url = InputBox("즐겨찾기 편집", "URL", b.Url);
        if (url == null) return;
        var idx = _source.IndexOf(b);
        if (idx >= 0) _source[idx] = new Bookmark(title.Trim(), url.Trim());
        _persist();
    }

    private void Delete_Click(object sender, RoutedEventArgs e)
    {
        if ((sender as FrameworkElement)?.DataContext is not Bookmark b) return;
        _source.Remove(b);
        _persist();
    }

    private void List_KeyDown(object sender, KeyEventArgs e)
    {
        if (e.Key == Key.Delete && List.SelectedItem is Bookmark b)
        {
            _source.Remove(b);
            _persist();
            e.Handled = true;
        }
    }

    /// <summary>UC-M19 브라우저 호환 Netscape 북마크 HTML 로 내보내기.</summary>
    private void Export_Click(object sender, RoutedEventArgs e)
    {
        var dlg = new Microsoft.Win32.SaveFileDialog { Filter = "북마크 HTML|*.html", FileName = "bookmarks.html" };
        if (dlg.ShowDialog() != true) return;
        var sb = new System.Text.StringBuilder();
        sb.AppendLine("<!DOCTYPE NETSCAPE-Bookmark-file-1>");
        sb.AppendLine("<META HTTP-EQUIV=\"Content-Type\" CONTENT=\"text/html; charset=UTF-8\">");
        sb.AppendLine("<TITLE>Bookmarks</TITLE><H1>Bookmarks</H1><DL><p>");
        foreach (var b in _source)
            sb.AppendLine($"    <DT><A HREF=\"{System.Net.WebUtility.HtmlEncode(b.Url)}\">{System.Net.WebUtility.HtmlEncode(b.Title)}</A>");
        sb.AppendLine("</DL><p>");
        File.WriteAllText(dlg.FileName, sb.ToString());
    }

    /// <summary>Netscape HTML 에서 HREF/제목 쌍을 추출해 추가 가져오기.</summary>
    private void Import_Click(object sender, RoutedEventArgs e)
    {
        var dlg = new Microsoft.Win32.OpenFileDialog { Filter = "북마크 HTML|*.html;*.htm" };
        if (dlg.ShowDialog() != true) return;
        try
        {
            var html = File.ReadAllText(dlg.FileName);
            var added = 0;
            foreach (var (url, title) in ParseNetscapeBookmarks(html))
            {
                if (_source.Any(b => b.Url.Equals(url, StringComparison.OrdinalIgnoreCase))) continue;
                _source.Add(new Bookmark(title, url));
                added++;
            }
            _persist();
            MessageBox.Show(this, $"{added}개 항목을 가져왔습니다", "가져오기");
        }
        catch (Exception ex)
        {
            MessageBox.Show(this, $"가져오기 실패: {ex.Message}", "가져오기", MessageBoxButton.OK, MessageBoxImage.Warning);
        }
    }

    internal static IEnumerable<(string Url, string Title)> ParseNetscapeBookmarks(string html)
    {
        var matches = System.Text.RegularExpressions.Regex.Matches(html,
            @"<A\s[^>]*HREF=""(?<url>[^""]+)""[^>]*>(?<title>.*?)</A>",
            System.Text.RegularExpressions.RegexOptions.IgnoreCase);
        foreach (System.Text.RegularExpressions.Match m in matches)
        {
            var url = System.Net.WebUtility.HtmlDecode(m.Groups["url"].Value);
            var title = System.Text.RegularExpressions.Regex.Replace(m.Groups["title"].Value, "<[^>]+>", "");
            yield return (url, System.Net.WebUtility.HtmlDecode(title).Trim());
        }
    }

    private string? InputBox(string title, string label, string initial)
    {
        var box = new TextBox { Text = initial, Style = (Style)FindResource("DarkTextBox"), Margin = new Thickness(0, 6, 0, 12) };
        var win = new Window
        {
            Title = title,
            Width = 440,
            SizeToContent = SizeToContent.Height,
            WindowStartupLocation = WindowStartupLocation.CenterOwner,
            Owner = this,
            Background = (System.Windows.Media.Brush)FindResource("WindowBg"),
        };
        var cancel = new Button { Content = "취소", Style = (Style)FindResource("GhostButton"), Width = 80, Margin = new Thickness(0, 0, 8, 0) };
        var ok = new Button { Content = "확인", Style = (Style)FindResource("PrimaryButton"), Width = 80, IsDefault = true };
        cancel.Click += (_, _) => win.DialogResult = false;
        ok.Click += (_, _) => win.DialogResult = true;
        win.Content = new StackPanel { Margin = new Thickness(16) }.Also(p =>
        {
            p.Children.Add(new TextBlock { Text = label, Foreground = (System.Windows.Media.Brush)FindResource("TextSecondary") });
            p.Children.Add(box);
            p.Children.Add(new StackPanel
            {
                Orientation = Orientation.Horizontal,
                HorizontalAlignment = HorizontalAlignment.Right,
                Children = { cancel, ok },
            });
        });
        return win.ShowDialog() == true ? box.Text : null;
    }

    private void Close_Click(object sender, RoutedEventArgs e) => Close();
}

/// <summary>람다식 객체 초기화 헬퍼(BookmarkManagerWindow 입력 다이얼로그용).</summary>
internal static class UiExtensions
{
    public static T Also<T>(this T self, Action<T> init)
    {
        init(self);
        return self;
    }
}