using System.ComponentModel;
using Microsoft.Win32;

namespace UI_WinForms.Components;

[DefaultEvent(nameof(LoadProject))]
public partial class LoaderStart : UserControl
{
    private bool areRecentProjectsVisible = false;

    public LoaderStart()
    {
        this.InitializeComponent();
    }

    #region Recent Projects

    private static RegistryKey I18NCommanderKey => Registry.CurrentUser.OpenSubKey("Software", RegistryKeyPermissionCheck.ReadWriteSubTree)!.CreateSubKey("I18N Commander", RegistryKeyPermissionCheck.ReadWriteSubTree);
    
    /// <summary>
    /// Gets or sets the list of recent projects without any extras e.g. it does not prune the list of projects.
    /// </summary>
    private static List<string> RecentProjects
    {
        get
        {
            using var regKey = LoaderStart.I18NCommanderKey;
            var recentProjectsValue = regKey.GetValue("recentProjects");
            return recentProjectsValue switch
            {
                string[] list => new List<string>(list),
                _ => new List<string>(),
            };
        }

        set
        {
            using var regKey = LoaderStart.I18NCommanderKey;
            regKey.SetValue("recentProjects", value.ToArray(), RegistryValueKind.MultiString);
        }
    }

    private static void UpdateRecentProjectsWithPruning(string latestUsedProjectPath)
    {
        var previousRecentList = LoaderStart.RecentProjects;
        
        // Check, if the latest project is identical to the next project we open. In that case, we don't add it to the list.
        if (previousRecentList.Any() && previousRecentList[0] == latestUsedProjectPath)
            return;

        // Add the next project to the list:
        previousRecentList.Insert(0, latestUsedProjectPath);
        
        // Prune the list:
        if (previousRecentList.Count > 6)
            previousRecentList = previousRecentList.Take(6).ToList();

        LoaderStart.RecentProjects = previousRecentList;
    }

    #endregion

    private void buttonOpen_Click(object sender, EventArgs e)
    {
        if(this.DesignMode)
            return;
        
        if(this.areRecentProjectsVisible)
        {
            this.areRecentProjectsVisible = false;
            this.contextMenuRecentProjects.Close();
            return;
        }

        var recentProjects = LoaderStart.RecentProjects;
        this.contextMenuRecentProjects.Items.Clear();
        this.contextMenuRecentProjects.Items.Add("Browse for project...", Resources.Icons.icons8_browse_folder_512, (innerSender, args) => this.BrowseForProject());
        foreach (var recentProject in recentProjects)
        {
            var fileInfo = new FileInfo(recentProject);
            
            // Split the file's path into each folder's name:
            var folderNames = fileInfo.DirectoryName!.Split(Path.DirectorySeparatorChar);
            
            // Render this entry:
            var item = this.contextMenuRecentProjects.Items.Add($"{folderNames.Last()}: {fileInfo.Name}", Resources.Icons.icons8_document_512, (innerSender, args) => this.OpenRecentProject(innerSender));
            item.Tag = recentProject;
        }

        var button = (sender as Button)!;
        this.contextMenuRecentProjects.Show(button, 0, button.Height);
        this.areRecentProjectsVisible = true;
    }

    private void buttonNew_Click(object sender, EventArgs e)
    {
        if(this.DesignMode)
            return;
        
        var saveDialog = new SaveFileDialog
        {
            AddExtension = true,
            CheckPathExists = true,
            CheckFileExists = false,
            CreatePrompt = false,
            OverwritePrompt = true,
            DereferenceLinks = true,
            DefaultExt = ".i18nc",
            Filter = "I18N Commander Files (*.i18nc)|*.i18nc",
            RestoreDirectory = true,
            Title = "Create a new I18N Commander file",
        };

        var dialogResult = saveDialog.ShowDialog(this);
        if (dialogResult != DialogResult.OK)
            return;

        var destinationFilePath = saveDialog.FileName;
        
        // When the user chose an existing file, we delete it:
        // (note: the user already accepts overwriting the file)
        if (File.Exists(destinationFilePath))
            File.Delete(destinationFilePath);
        
        LoaderStart.UpdateRecentProjectsWithPruning(destinationFilePath);
        this.OpenProject(destinationFilePath);
    }

    private void BrowseForProject()
    {
        var openDialog = new OpenFileDialog
        {
            AddExtension = true,
            CheckPathExists = true,
            CheckFileExists = true,
            DereferenceLinks = true,
            DefaultExt = ".i18nc",
            Filter = "I18N Commander Files (*.i18nc)|*.i18nc",
            Multiselect = false,
            RestoreDirectory = true,
            Title = "Open an I18N Commander file",
        };
        var dialogResult = openDialog.ShowDialog(this);
        if (dialogResult != DialogResult.OK)
            return;

        var projectFilePath = openDialog.FileName;
        LoaderStart.UpdateRecentProjectsWithPruning(projectFilePath);
        this.OpenProject(projectFilePath);
    }

    private void OpenRecentProject(object? sender)
    {
        if (sender is not ToolStripItem item)
            return;

        var path = (item.Tag as string)!;
        LoaderStart.UpdateRecentProjectsWithPruning(path);
        this.OpenProject(path);
    }

    private void OpenProject(string path)
    {
        // Hint: the project file might or might not exist (new project vs. recent project)
        this.LoadProject?.Invoke(this, path);
    }

    private void contextMenuRecentProjects_Closing(object sender, ToolStripDropDownClosingEventArgs e)
    {
        this.areRecentProjectsVisible = false;
    }

    [Category("Settings"), Description("When the user chooses a project to load.")]
    public event EventHandler<string>? LoadProject;
}