using System;
using System.Drawing;
using System.Runtime.InteropServices;
using System.Windows.Forms;
using Katteker.Gui.Properties;

namespace Katteker.Gui
{
    public sealed partial class UpdateWindow : Form
    {
        private const int HTCAPTION = 0x2;
        private const int WM_NCLBUTTONDOWN = 0xA1;

        /// <summary>
        /// The Update Window
        /// </summary>
        public UpdateWindow()
        {
            Font = SystemFonts.MessageBoxFont;
            Application.EnableVisualStyles();
            if (Environment.OSVersion.Version.Major >= 6)
                SetProcessDPIAware();
            InitializeComponent();
        }

        private string Changelog => UpdateManager.ChangelogFilename;
        
        /// <summary>
        /// Last release entry.
        /// </summary>
        public ReleaseEntry ReleaseEntry { get; set; }

        /// <summary>
        /// Update manager
        /// </summary>
        public UpdateManager UpdateManager { get; set; }

        private string PublishPath => UpdateManager.UrlOrPath;
        
        /// <inheritdoc />
        /// <summary>
        /// Clean up any resources being used.
        /// </summary>
        /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
        protected override void Dispose(bool disposing)
        {
            if (disposing)
            {
                components?.Dispose();
            }
            base.Dispose(disposing);
        }

        [DllImport("User32.dll")]
        private static extern bool ReleaseCapture();

        [DllImport("User32.dll")]
        private static extern int SendMessage(IntPtr hWnd, int Msg, int wParam, int lParam);

        [DllImport("user32.dll")]
        private static extern bool SetProcessDPIAware();
        private void CloseBtn_Click(object sender, EventArgs e)
        {
            Close();
        }

        private void MaximizeBtn_Click(object sender, EventArgs e)
        {
            WindowState = WindowState != FormWindowState.Maximized ? FormWindowState.Maximized : FormWindowState.Normal;
        }

        private void MinimizeBtn_Click(object sender, EventArgs e)
        {
            WindowState = FormWindowState.Minimized;
        }

        private void Titlebar_MouseDown(object sender, MouseEventArgs e)
        {
            if (e.Button != MouseButtons.Left) return;
            ReleaseCapture();
            SendMessage(Handle, WM_NCLBUTTONDOWN, HTCAPTION, 0);
        }

        private async void UpdateWindow_Load(object sender, EventArgs e)
        {
            var changelog = await ChangelogHelper.LoadChangelogAsync(Changelog, PublishPath).ConfigureAwait(false);
            Invoke(new Action(() => changelogBrowser.DocumentText = changelog));
            if (ReleaseEntry == null)
            {
                Invoke(new Action(() => { WriteTitle(Resources.No_update_available); }));
            }
            else
            {
                var latest = ReleaseEntry.Version;
                Invoke(new Action(() =>
                {
                    WriteTitle(Resources.You_can_update_to_Version + latest);
                    updBtn.Visible = true;
                }));
            }
        }

        private async void UpdBtn_Click(object sender, EventArgs e)
        {
            Invoke(new Action(() => progressBar1.Visible = true));

            try
            {
                var progress = new Progress<int>(x => Invoke(new Action(() => { progressBar1.Value = x; })));
                await UpdateManager.UpdateAppAsync(progress).ConfigureAwait(false);

                WriteTitle(Resources.You_re_up_to_date);
            }
            catch (Exception ex)
            {
                WriteTitle(ex.Message);
            }
            finally
            {
                Invoke(new Action(() =>
                {
                    progressBar1.Visible = false;
                    updBtn.Visible = false;
                    var messResult = MessageBox.Show(
                        Resources.Installed_new_Version,
                        Resources.New_Version,
                        MessageBoxButtons.YesNo,
                        MessageBoxIcon.Question);
                    if (messResult == DialogResult.Yes)
                    {
                        DialogResult = DialogResult.OK;
                        Close();
                    }
                }));
            }
        }
        private void WriteTitle(string text)
        {
            Invoke(new Action(() =>
            {
                Text = text;
                titlebar.Text = text;
            }));
        }
    }
}