using System;
using System.Drawing;
using System.Windows.Forms;

namespace EveOPreview.View.Implementation {
    public partial class RegionPickerDialog : Form {
        private Point _startPoint;
        private Point _endPoint;
        private bool _isDrawing;
        private Rectangle _selectedRegion;

        public Rectangle SelectedRegion => _selectedRegion;

        public RegionPickerDialog() {
            InitializeComponent();
            InitializeDialog();
        }

        private void InitializeDialog() {
            // Make the form cover all screens
            Rectangle totalBounds = GetTotalScreenBounds();
            this.Bounds = totalBounds;
            this.StartPosition = FormStartPosition.Manual;
            this.FormBorderStyle = FormBorderStyle.None;
            this.WindowState = FormWindowState.Maximized;
            this.TopMost = true;
            this.ShowInTaskbar = false;
            this.Cursor = Cursors.Cross;

            // Make the form semi-transparent but not fully transparent
            this.BackColor = Color.Black;
            this.Opacity = 0.3;

            // Add event handlers
            this.MouseDown += RegionPickerDialog_MouseDown;
            this.MouseMove += RegionPickerDialog_MouseMove;
            this.MouseUp += RegionPickerDialog_MouseUp;
            this.KeyDown += RegionPickerDialog_KeyDown;
            this.Paint += RegionPickerDialog_Paint;

            // Add instructions label
            var instructionsLabel = new Label { Text = "Click and drag to select a region. Press ESC to cancel.",
                                                ForeColor = Color.White,
                                                BackColor = Color.Black,
                                                Font = new Font("Arial", 12, FontStyle.Bold),
                                                AutoSize = true,
                                                Location = new Point(10, 10) };
            this.Controls.Add(instructionsLabel);
        }

        private Rectangle GetTotalScreenBounds() {
            Rectangle bounds = Screen.PrimaryScreen.Bounds;
            foreach (Screen screen in Screen.AllScreens) {
                bounds = Rectangle.Union(bounds, screen.Bounds);
            }
            return bounds;
        }

        private void RegionPickerDialog_MouseDown(object sender, MouseEventArgs e) {
            if (e.Button == MouseButtons.Left) {
                _startPoint = e.Location;
                _isDrawing = true;
                this.Capture = true;
                this.Invalidate();
            }
        }

        private void RegionPickerDialog_MouseMove(object sender, MouseEventArgs e) {
            if (_isDrawing) {
                _endPoint = e.Location;
                this.Invalidate();
            }
        }

        private void RegionPickerDialog_MouseUp(object sender, MouseEventArgs e) {
            if (e.Button == MouseButtons.Left && _isDrawing) {
                _isDrawing = false;
                _endPoint = e.Location;
                this.Capture = false;

                // Calculate the selected region
                int x = Math.Min(_startPoint.X, _endPoint.X);
                int y = Math.Min(_startPoint.Y, _endPoint.Y);
                int width = Math.Abs(_endPoint.X - _startPoint.X);
                int height = Math.Abs(_endPoint.Y - _startPoint.Y);

                if (width > 10 && height > 10)  // Minimum size
                {
                    _selectedRegion = new Rectangle(x, y, width, height);
                    this.DialogResult = DialogResult.OK;
                    this.Close();
                } else {
                    // Reset if region is too small
                    _startPoint = Point.Empty;
                    _endPoint = Point.Empty;
                    this.Invalidate();
                }
            }
        }

        private void RegionPickerDialog_KeyDown(object sender, KeyEventArgs e) {
            if (e.KeyCode == Keys.Escape) {
                this.DialogResult = DialogResult.Cancel;
                this.Close();
            }
        }

        private void RegionPickerDialog_Paint(object sender, PaintEventArgs e) {
            if (_isDrawing) {
                // Draw selection rectangle
                using (Pen pen = new Pen(Color.Red, 2)) {
                    pen.DashStyle = System.Drawing.Drawing2D.DashStyle.Dash;

                    int x = Math.Min(_startPoint.X, _endPoint.X);
                    int y = Math.Min(_startPoint.Y, _endPoint.Y);
                    int width = Math.Abs(_endPoint.X - _startPoint.X);
                    int height = Math.Abs(_endPoint.Y - _startPoint.Y);

                    e.Graphics.DrawRectangle(pen, x, y, width, height);
                }

                // Draw size information
                if (_startPoint != Point.Empty && _endPoint != Point.Empty) {
                    int width = Math.Abs(_endPoint.X - _startPoint.X);
                    int height = Math.Abs(_endPoint.Y - _startPoint.Y);

                    string sizeText = $"{width} x {height}";
                    using (Font font = new Font("Arial", 10, FontStyle.Bold)) using (Brush brush =
                                                                                         new SolidBrush(Color.White)) {
                        e.Graphics.DrawString(sizeText, font, brush, _endPoint.X + 5, _endPoint.Y + 5);
                    }
                }
            }
        }
    }
}