#region License Information
/* HeuristicLab
 * Copyright (C) 2002-2015 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
 *
 * This file is part of HeuristicLab.
 *
 * HeuristicLab is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * HeuristicLab is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
 */
#endregion

using System;
using System.Linq;
using System.Reflection;
using System.Windows.Forms;

namespace HeuristicLab.PluginInfrastructure.UI {
  public partial class SplashScreen : Form {
    private const int FADE_INTERVAL = 50;
    private Timer fadeTimer;
    private int initialInterval;

    private SplashScreen() {
      InitializeComponent();
    }

    public SplashScreen(string initialText, int initialInterval)
      : this() {
      this.initialInterval = initialInterval;

      var entryAssembly = Assembly.GetEntryAssembly();
      // RegisterPluginManagerEventHandlers();

      versionLabel.Text = "Version " + entryAssembly.GetFileVersion() + " "
        + entryAssembly.GetCustomAttributes().OfType<AssemblyInformationalVersionAttribute>().First().InformationalVersion; // code name
      infoLabel.Text = "";

      var attr = entryAssembly.GetCustomAttributes().OfType<AssemblyCopyrightAttribute>().Single();
      copyrightLabel.Text = "Copyright " + attr.Copyright;

      fadeTimer = new Timer();
      fadeTimer.Tick += fadeTimer_Elapsed;
      fadeTimer.Interval = initialInterval;
      fadeTimer.Start();

      Opacity = 1;
      infoLabel.Text = initialText;

    }

    public void UpdateMessage(string msg) {
      try {
        if (InvokeRequired) Invoke((Action<string>)UpdateMessage, msg);
        else {
          ResetFadeTimer();
          infoLabel.Text = msg;
        }
      } catch (ObjectDisposedException) { }
    }

    // each tick of the timer reduce opacity and restart timer
    private void fadeTimer_Elapsed(object sender, EventArgs e) {
      // only called from local timer: no need to invoke here
      FadeOut();
    }

    private void ResetFadeTimer() {
      // wait initialInterval again for the first tick
      fadeTimer.Stop();
      fadeTimer.Interval = initialInterval;
      fadeTimer.Start();
    }

    // reduces opacity of the splashscreen one step and restarts the fade-timer
    private void FadeOut() {
      fadeTimer.Stop();
      fadeTimer.Interval = FADE_INTERVAL;
      if (this.Opacity > 0) {
        Opacity -= 0.1;
        fadeTimer.Start();
      } else {
        Opacity = 0;
        fadeTimer.Stop();
        Close();
      }
    }
  }
}