PDFPatcher/App/Common/ObjectListViewHelper.cs

using System;
using System.Collections.Generic;
using System.Drawing;
using System.Drawing.Drawing2D;
using CLR;

namespace BrightIdeasSoftware;

static class ObjectListViewHelper
{
	/// <summary>修复编辑控件太窄小的问题。</summary>
	public static void FixEditControlWidth(this ObjectListView view) {
		view.CellEditStarting += View_CellEditStarting;
		view.Disposed += View_Disposed;
	}

	public static bool HasSelection(this ObjectListView view) {
		return view.SelectedIndices.Count > 0;
	}

	static void View_Disposed(object sender, EventArgs e) {
		var view = (ObjectListView)sender;
		view.CellEditStarting -= View_CellEditStarting;
		view.Disposed -= View_Disposed;
	}

	static void View_CellEditStarting(object sender, CellEditEventArgs e) {
		var b = e.CellBounds;
		if (b.Width < 60) {
			b.Width = 60;
		}
		if (e.Control is System.Windows.Forms.Control c) {
			c.Bounds = b;
			c.Location = b.Location;
		}
	}

	public static void RedrawItem(this ObjectListView view, int index) {
		var c = view.GetItemCount();
		if (c > 0 && index.IsBetween(0, c - 1)) {
			view.RedrawItems(Math.Max(0, index - 1), Math.Min(index + 1, c - 1), true);
		}
	}

	public static void SetTreeViewLine(this TreeListView view) {
		var tcr = view.TreeColumnRenderer as TreeListView.TreeRenderer;
		tcr.LinePen = new Pen(SystemColors.ControlDark) {
			DashCap = DashCap.Round,
			DashStyle = DashStyle.Dash
		};
	}

	public static void ExpandSelected(this TreeListView view, bool moveToFirstChild = false) {
		if (!view.HasSelection()) {
			return;
		}
		var so = view.SelectedObjects;
		var expanded = false;
		foreach (var item in so) {
			if (!view.IsExpanded(item)) {
				view.Expand(item);
				expanded = true;
			}
		}
		if (moveToFirstChild && !expanded) {
			foreach (var ch in view.GetChildren(so[0])) {
				view.SelectedObject = view.FocusedObject = ch;
				return;
			}
		}
	}
	public static void Expand(this TreeListView view, System.Collections.IEnumerable items, bool recursive) {
		foreach (var item in items) {
			view.Expand(item);
			if (recursive) {
				view.Expand(view.GetChildren(item), true);
			}
		}
	}
	public static void Collapse(this TreeListView view, System.Collections.IEnumerable items, bool recursive) {
		foreach (var item in items) {
			if (recursive && view.IsExpanded(item)) {
				view.Collapse(view.GetChildren(item), true);
			}
			view.Collapse(item);
		}
	}

	public static TypedObjectListView<T> AsTyped<T>(this ObjectListView view) where T : class {
		return view.AsTyped<T>(null);
	}

	public static TypedObjectListView<T> AsTyped<T>(this ObjectListView view, Action<TypedObjectListView<T>> configurator) where T : class {
		var v = new TypedObjectListView<T>(view);
		configurator?.Invoke(v);
		return v;
	}
	public static TypedObjectListView<T> ConfigColumn<T>(this TypedObjectListView<T> view, OLVColumn column, Action<TypedColumn<T>> configurator) where T : class {
		var t = new TypedColumn<T>(column);
		configurator(t);
		return view;
	}
	public static TypedColumn<T> AsTyped<T>(this OLVColumn column, Action<TypedColumn<T>> configurator) where T : class {
		var t = new TypedColumn<T>(column);
		configurator(t);
		return t;
	}
	public static T GetParentModel<T>(this TreeListView view, T model) where T : class {
		return view.GetParent(model) as T;
	}

	public static List<T> GetAncestorsOrSelf<T>(this TreeListView view, T model) where T : class {
		var r = new List<T>();
		do {
			r.Add(model);
		} while ((model = view.GetParent(model) as T) != null);
		return r;
	}

	public static void CollapseSelected(this TreeListView view, bool moveToParent = false) {
		if (!view.HasSelection()) {
			return;
		}
		var so = view.SelectedObjects;
		var collapsed = false;
		foreach (var item in so) {
			if (view.IsExpanded(item)) {
				view.Collapse(item);
				collapsed = true;
			}
		}
		if (moveToParent && !collapsed) {
			var parent = view.GetParent(so[0]);
			if (parent != null) {
				view.SelectedObject = view.FocusedObject = parent;
			}
		}
	}

	public static void MoveUpSelection(this ObjectListView view) {
		var si = view.GetFirstSelectedIndex();
		if (si < 1) {
			return;
		}
		var so = view.SelectedObjects;
		view.MoveObjects(--si, so);
		view.SelectedObjects = so;
	}

	public static void MoveDownSelection(this ObjectListView view) {
		var ls = view.GetLastItemInDisplayOrder();
		if (ls == null || ls.Selected == true) {
			return;
		}
		var si = view.GetFirstSelectedIndex();
		if (si < 0) {
			return;
		}
		var so = view.SelectedObjects;
		view.MoveObjects(si + 2, so);
		view.SelectedObjects = so;
	}

	public static T GetFirstSelectedModel<T>(this ObjectListView view) where T : class {
		return view.GetModelObject(view.GetFirstSelectedIndex()) as T;
	}

	public static OLVListItem GetFocusedOrFirstSelectedItem(this ObjectListView view) {
		return view.GetItemCount() == 0 ? null
			: (view.FocusedItem
			?? view.SelectedItem
			?? (view.HasSelection() ? view.GetItem(view.SelectedIndices[0]) : null)) as OLVListItem;
	}

	public static void SelectPrevious(this ObjectListView view) {
		var si = view.GetFocusedOrFirstSelectedItem();
		if (si == null) {
			if (view.GetItemCount() != 0) {
				(view.SelectedItem = view.GetItem(0)).Focused = true;
			}
			return;
		}

		int i;
		if ((i = si.Index) < 1) {
			return;
		}
		(view.SelectedItem = view.GetItem(--i)).Focused = true;
		view.EnsureVisible(i);
	}
	public static void SelectNext(this ObjectListView view) {
		var si = view.GetFocusedOrFirstSelectedItem();
		if (si == null) {
			if (view.GetItemCount() != 0) {
				(view.SelectedItem = view.GetItem(0)).Focused = true;
			}
			return;
		}

		int i;
		if ((i = si.Index) == view.GetItemCount() - 1) {
			return;
		}
		(view.SelectedItem = view.GetItem(++i)).Focused = true;
		view.EnsureVisible(i);
	}

	// 树视图存在子节点且多选节点时，在 SelectedIndexChanged 事件中，SelectedIndices属性可能返回无内容的集合。
	public static int GetFirstSelectedIndex(this ObjectListView view) {
		var c = view.GetItemCount();
		int i = c;
		foreach (int item in view.SelectedIndices) {
			if (item < i) {
				i = item;
			}
		}
		return i == c ? -1 : i;
	}

	public static int GetLastSelectedIndex(this ObjectListView view) {
		int i = -1;
		foreach (int item in view.SelectedIndices) {
			if (item > i) {
				i = item;
			}
		}
		return i;
	}

	public static List<T> GetSelectedModels<T>(this ObjectListView view) where T : class {
		var s = view.SelectedObjects;
		var r = new List<T>(s.Count);
		foreach (T item in s) {
			if (item != null) {
				r.Add(item);
			}
		}
		return r;
	}

	/// <summary>测试坐标点属于哪个单元格。</summary>
	public static GridTestResult GetGridAt(this ObjectListView view, int x, int y) {
		var cr = view.ContentRectangle;
		var ic = view.GetItemCount();
		var ob = false;
		if (x < cr.Left) {
			x = cr.Left;
			ob = true;
		}
		else if (x >= cr.Right) {
			x = cr.Right - 1;
			ob = true;
		}
		var cb = cr.Top + ic * view.RowHeightEffective;
		if (y < cr.Top) {
			y = cr.Top;
			ob = true;
		}
		else if (y >= cb) {
			y = cb;
			ob = true;
		}
		var r = view.GetItemAt(x, y, out OLVColumn c);
		if (r != null) {
			return new GridTestResult(c.DisplayIndex, r.Index, ob);
		}
		// 当列表框滚动时，上述方法失效，使用此替补方法
		r = view.GetNthItemInDisplayOrder((y - 1 - cr.Top) / view.RowHeightEffective);
		var w = cr.Left;
		var cl = view.ColumnsInDisplayOrder;
		for (int i = 0; i < cl.Count; i++) {
			if (x >= w && x <= (w += cl[i].Width)) {
				c = cl[i];
				break;
			}
		}
		if (c == null) {
			c = cl[cl.Count - 1];
			ob = true;
		}
		y = r.Index + view.TopItemIndex;
		if (y >= view.GetItemCount()) {
			y = view.GetItemCount() - 1;
		}
		return new GridTestResult(c.DisplayIndex, y, ob);
	}

	public static void InvertSelect(this ObjectListView view) {
		view.Freeze();
		var l = view.GetItemCount();
		for (int i = 0; i < l; i++) {
			var oi = view.GetItem(i);
			oi.Selected = !oi.Selected;
		}
		view.Unfreeze();
	}
}

readonly struct GridTestResult(int columnIndex, int rowIndex, bool isOutOfRange)
{
	public int ColumnIndex { get; } = columnIndex;
	public int RowIndex { get; } = rowIndex;
	public bool IsOutOfRange { get; } = isOutOfRange;
}