using System.Windows;
using System.Windows.Threading;
using Microsoft.EntityFrameworkCore;
using SimpleWiki.Data;
using SimpleWiki.Models;
using SimpleWiki.Services;

namespace SimpleWiki.Views;

public partial class MainWindow : Window
{
    private readonly User _currentUser;
    private bool _isArticleBrowserReady;
    private string _pendingArticleHtml = string.Empty;

    public MainWindow(User currentUser)
    {
        InitializeComponent();
        _currentUser = currentUser;
        _pendingArticleHtml = MarkdownService.ToHtmlDocument("Simple Wiki", "## Загрузка...");
        Loaded += MainWindow_Loaded;
        ContentRendered += MainWindow_ContentRendered;
    }

    private void MainWindow_ContentRendered(object? sender, EventArgs e)
    {
        _isArticleBrowserReady = true;
        Dispatcher.BeginInvoke(RenderArticleIfReady, DispatcherPriority.ApplicationIdle);
    }

    private void MainWindow_Loaded(object sender, RoutedEventArgs e)
    {
        FullNameTextBlock.Text = _currentUser.FullName;
        EmailTextBlock.Text = _currentUser.Email;
        RoleTextBlock.Text = _currentUser.Role == Roles.Admin ? "Роль: администратор" : "Роль: пользователь";
        CreatedAtTextBlock.Text = $"Дата регистрации: {_currentUser.CreatedAt.ToLocalTime():dd.MM.yyyy HH:mm}";

        var isAdmin = _currentUser.Role == Roles.Admin;
        AdminToolbar.Visibility = isAdmin ? Visibility.Visible : Visibility.Collapsed;

        LoadArticles();
    }

    private void LoadArticles(string? query = null)
    {
        using var db = new AppDbContext();
        var items = db.Articles
            .Include(x => x.Author)
            .OrderByDescending(x => x.UpdatedAt ?? x.CreatedAt)
            .AsQueryable();

        if (!string.IsNullOrWhiteSpace(query))
        {
            var term = query.Trim().ToLower();
            items = items.Where(x => x.Title.ToLower().Contains(term) || x.Summary.ToLower().Contains(term));
        }

        var articles = items.ToList();
        ArticlesListBox.ItemsSource = articles;

        if (articles.Count > 0)
        {
            ArticlesListBox.SelectedIndex = 0;
        }
        else
        {
            ArticleTitleTextBlock.Text = "Статей пока нет";
            ArticleSummaryTextBlock.Text = "Бебебе";
            ArticleMetaTextBlock.Text = string.Empty;
            _pendingArticleHtml = MarkdownService.ToHtmlDocument("Empty", "## Пусто\n\nПока нечего читать.");
            RenderArticleIfReady();
        }
    }

    private void ArticlesListBox_SelectionChanged(object sender, System.Windows.Controls.SelectionChangedEventArgs e)
    {
        if (ArticlesListBox.SelectedItem is not Article selectedArticle)
        {
            return;
        }

        using var db = new AppDbContext();
        var article = db.Articles
            .Include(x => x.Author)
            .FirstOrDefault(x => x.Id == selectedArticle.Id);

        if (article is null)
        {
            return;
        }

        ArticleTitleTextBlock.Text = article.Title;
        ArticleSummaryTextBlock.Text = article.Summary;
        ArticleMetaTextBlock.Text = $"Автор: {article.Author?.FullName} | Создано: {article.CreatedAt.ToLocalTime():dd.MM.yyyy HH:mm}" +
                                    (article.UpdatedAt.HasValue ? $" | Обновлено: {article.UpdatedAt.Value.ToLocalTime():dd.MM.yyyy HH:mm}" : string.Empty);

        _pendingArticleHtml = MarkdownService.ToHtmlDocument(article.Title, article.MarkdownContent);
        RenderArticleIfReady();
    }


    private void RenderArticleIfReady()
    {
        if (!_isArticleBrowserReady)
        {
            return;
        }

        ArticleBrowser.NavigateToString(_pendingArticleHtml);
    }

    private void SearchTextBox_TextChanged(object sender, System.Windows.Controls.TextChangedEventArgs e)
    {
        LoadArticles(SearchTextBox.Text);
    }

    private void AddArticleButton_Click(object sender, RoutedEventArgs e)
    {
        var editor = new ArticleEditorWindow(_currentUser);
        if (editor.ShowDialog() == true)
        {
            LoadArticles(SearchTextBox.Text);
        }
    }

    private void EditArticleButton_Click(object sender, RoutedEventArgs e)
    {
        if (ArticlesListBox.SelectedItem is not Article article)
        {
            MessageBox.Show("Сначала выберите статью.", "Внимание", MessageBoxButton.OK, MessageBoxImage.Warning);
            return;
        }

        var editor = new ArticleEditorWindow(_currentUser, article.Id);
        if (editor.ShowDialog() == true)
        {
            LoadArticles(SearchTextBox.Text);
        }
    }

    private void DeleteArticleButton_Click(object sender, RoutedEventArgs e)
    {
        if (ArticlesListBox.SelectedItem is not Article article)
        {
            MessageBox.Show("Сначала выберите статью.", "Внимание", MessageBoxButton.OK, MessageBoxImage.Warning);
            return;
        }

        var result = MessageBox.Show($"Удалить статью '{article.Title}'?", "Подтверждение", MessageBoxButton.YesNo, MessageBoxImage.Question);
        if (result != MessageBoxResult.Yes)
        {
            return;
        }

        using var db = new AppDbContext();
        var entity = db.Articles.FirstOrDefault(x => x.Id == article.Id);
        if (entity is null)
        {
            return;
        }

        db.Articles.Remove(entity);
        db.SaveChanges();
        LoadArticles(SearchTextBox.Text);
    }

    private void LogoutButton_Click(object sender, RoutedEventArgs e)
    {
        SessionService.CurrentUser = null;
        new LoginWindow().Show();
        Close();
    }
}