JD2022-TU1/main/tools/framework/JD.Sequencers/Tools/SelectingTool.cs

using System;
using System.Drawing;
using System.Windows.Forms;
using JD.Kernel.Structs;
using JD.Sequencers.Controls;
using JD.Sequencers.Windowlesses;

namespace JD.Sequencers.Tools
{
    /// <summary>
    /// Basic tool that selects controls.
    /// </summary>
    public class SelectingTool : Tool
    {
        #region Variables

        private bool m_allowMultiselection = true;

        #endregion

        #region Constructor

        /// <summary>
        /// Constructor.
        /// </summary>
        /// <param name="owner"></param>
        public SelectingTool(WindowlessContainer owner)
            : base(owner)
        {
        }

        #endregion

        #region Properties

        /// <summary>
        /// Whether to allow multi-selection.
        /// </summary>
        public bool AllowMultiselection
        {
            get
            {
                return m_allowMultiselection;
            }
            set
            {
                m_allowMultiselection = value;
            }
        }

        #endregion

        #region Methods

        /// <summary>
        /// Overriden.
        /// </summary>
        /// <param name="e"></param>
        /// <returns></returns>
        protected internal override bool CanStart(ToolStartingEventArgs e)
        {
            return (e.Button == MouseButtons.Left || e.Button == MouseButtons.Right) && base.CanStart(e);
        }

        private bool CanSelect(WindowlessControl control)
        {
            return Selection.Count == 0 || AllowMultiselection;
        }

        protected internal override void OnMouseDown(MouseEventArgs e)
        {
            base.OnMouseDown(e);

            DoSingleSelection(e.Button, e.Location, SelectionType.MouseDown);
        }

        protected internal override void OnMouseUp(MouseEventArgs e)
        {
            base.OnMouseUp(e);

            DoSingleSelection(e.Button, e.Location, SelectionType.MouseUp);
        }

        [Flags]
        protected enum SelectionType
        {
            MouseDown = 1,
            MouseUp = 2
        }

        protected void DoSingleSelection(MouseButtons button, Point location, Flags<SelectionType> selectionType)
        {
            CurrentControl = Container.FindSelectableControl<WindowlessControl>(location);

            if (CurrentControl != null)
            {
                if (IsControlPressed && selectionType[SelectionType.MouseDown])
                {
                    if (CurrentControl.Selected)
                    {
                        Selection.Remove(CurrentControl);
                    }
                    else if (CanSelect(CurrentControl))
                    {
                        AddToSelection(CurrentControl);
                        Selection.PerformMultiSelect();
                    }
                }
                else if (IsShiftPressed && CanSelect(CurrentControl) && selectionType[SelectionType.MouseDown])
                {
                    AddToSelection(CurrentControl);
                }
                else if (!IsShiftPressed && !IsControlPressed)
                {
                    if (!CurrentControl.Selected || (selectionType[SelectionType.MouseUp] && button == MouseButtons.Left))
                    {
                        Selection.Select(CurrentControl);
                    }
                }
            }
            else if (!IsControlPressed && !IsShiftPressed && selectionType[SelectionType.MouseUp])
            {
                Selection.Clear();
            }
        }

        private void AddToSelection(WindowlessControl control)
        {
            if (Selection.Count == 0 || Selection.Primary.CanSelectWith(control))
            {
                Selection.Add(control);
            }
        }

        /// <summary>
        /// Overriden.
        /// </summary>
        /// <param name="e"></param>
        protected internal override void OnMouseMove(MouseEventArgs e)
        {
            if (e.Location != LastMouseDownEventArgs.Location)
            {
                EndTool();
            }
        }

        #endregion
    }
}