using System;
using System.Collections.Generic;
using System.Drawing;
using System.Linq;
using System.Windows.Forms;
using HeliosDisplayManagement.Resources;
using WinFormAnimation;

namespace HeliosDisplayManagement.UIForms
{
    public sealed partial class SplashForm : Form
    {
        private readonly Action _job;
        private readonly Bitmap _progressImage;
        private readonly List<Point> _progressPositions = new List<Point>();
        private int _countdownCounter;
        private bool _isClosing;
        private int _startCounter;

        public SplashForm()
        {
            InitializeComponent();
            _progressImage = new Bitmap(progressPanel.Width, progressPanel.Height);
            Controls.Remove(progressPanel);
            progressPanel.BackColor = BackColor;
            progressBar.Invalidated += (sender, args) => Invalidate();
            progressPanel.Invalidated += (sender, args) => Invalidate();
        }

        public SplashForm(Action job, int cancellationTimeout = 0, int countdown = 0) : this()
        {
            _job = job;
            _startCounter = cancellationTimeout;
            _countdownCounter = countdown;
        }

        public string CancellationMessage { get; set; } = Language.Starting_in;
        public string CountdownMessage { get; set; } = Language.Please_wait;

        protected override void OnKeyDown(KeyEventArgs e)
        {
            e.Handled = true;
        }

        protected override void OnPaint(PaintEventArgs e)
        {
            lock (_progressPositions)
            {
                progressPanel.DrawToBitmap(_progressImage, new Rectangle(Point.Empty, progressPanel.Size));
                foreach (var position in _progressPositions)
                    e.Graphics.DrawImage(_progressImage, new Rectangle(position, progressPanel.Size));
            }
            base.OnPaint(e);
        }

        protected override bool ProcessCmdKey(ref Message msg, Keys keyData)
        {
            if (keyData != Keys.Escape)
                return base.ProcessCmdKey(ref msg, keyData);
            if (t_start.Enabled)
            {
                t_start.Stop();
                t_countdown.Stop();
                DialogResult = DialogResult.Cancel;
                Close();
                return true;
            }
            return true;
        }

        private void DoJob()
        {
            lbl_message.Text = CountdownMessage;
            progressBar.ProgressColor = Color.OrangeRed;
            if (_countdownCounter > 0)
            {
                progressBar.Text = (progressBar.Value = progressBar.Maximum = _countdownCounter).ToString();
                t_countdown.Start();
                _job?.Invoke();
            }
            else
            {
                progressBar.Style = ProgressBarStyle.Marquee;
                progressBar.Text = "";
                progressBar.Maximum = 100;
                progressBar.Value = 50;
                progressBar.Style = ProgressBarStyle.Marquee;
                _job?.Invoke();
                DialogResult = DialogResult.OK;
                Close();
            }
        }

        private void DoTimeout()
        {
            lbl_message.Text = CancellationMessage;
            progressBar.ProgressColor = Color.DodgerBlue;
            if (_startCounter > 0)
            {
                progressBar.Text = (progressBar.Value = progressBar.Maximum = _startCounter).ToString();
                t_start.Start();
            }
            else
            {
                DoJob();
            }
        }

        private void Reposition()
        {
            lock (_progressPositions)
            {
                var screens = Screen.AllScreens;
                var minX = screens.Select(screen => screen.Bounds.X).Concat(new[] {0}).Min();
                var maxX = screens.Select(screen => screen.Bounds.Width + screen.Bounds.X).Concat(new[] {0}).Max();
                var minY = screens.Select(screen => screen.Bounds.Y).Concat(new[] {0}).Min();
                var maxY = screens.Select(screen => screen.Bounds.Height + screen.Bounds.Y).Concat(new[] {0}).Max();

                Size = new Size(maxX + Math.Abs(minX), maxY + Math.Abs(minY));
                Location = new Point(minX, minY);

                _progressPositions.Clear();
                _progressPositions.AddRange(
                    screens.Select(
                        screen =>
                            new Point(screen.Bounds.X - minX + (screen.Bounds.Width - progressPanel.Width)/2,
                                screen.Bounds.Y - minY + (screen.Bounds.Height - progressPanel.Height)/2)));
            }
#if !DEBUG
            TopMost = true;
#endif
            Activate();
            Invalidate();
        }

        private void SplashForm_FormClosing(object sender, FormClosingEventArgs e)
        {
            if (_isClosing)
                return;
            _isClosing = true;
            e.Cancel = true;
            var dialogResult = DialogResult;
            new Animator(new Path((float) Opacity, 0, 200))
                .Play(new SafeInvoker<float>(f =>
                {
                    try
                    {
                        Opacity = f;
                    }
                    catch
                    {
                        // ignored
                    }
                }, this), new SafeInvoker(() =>
                {
                    DialogResult = dialogResult;
                    Close();
                }, this));
        }

        private void SplashForm_Reposition(object sender, EventArgs e)
        {
            Reposition();
        }

        private void SplashForm_Shown(object sender, EventArgs e)
        {
            new Animator(new Path((float) Opacity, 0.97f, 200))
                .Play(new SafeInvoker<float>(f =>
                {
                    try
                    {
                        Opacity = f;
                    }
                    catch
                    {
                        // ignored
                    }
                }, this), new SafeInvoker(DoTimeout, this));
        }

        private void t_countdown_Tick(object sender, EventArgs e)
        {
            if (_countdownCounter < 0)
            {
                t_countdown.Stop();
                DialogResult = DialogResult.OK;
                Close();
                return;
            }
            progressBar.Value = _countdownCounter;
            progressBar.Text = progressBar.Value.ToString();
            _countdownCounter--;
            Reposition();
        }

        private void t_start_Tick(object sender, EventArgs e)
        {
            if (_startCounter < 0)
            {
                t_start.Stop();
                DoJob();
                return;
            }
            progressBar.Value = _startCounter;
            progressBar.Text = progressBar.Value.ToString();
            _startCounter--;
            Reposition();
        }
    }
}