Connected.Components/Components/ExpansionPanel/ExpansionPanels.razor.cs

using System.Diagnostics.CodeAnalysis;
using Connected.Annotations;
using Connected.Utilities;
using Microsoft.AspNetCore.Components;

namespace Connected.Components;

public partial class ExpansionPanels : UIComponent
{
	protected string Classname =>
	new CssBuilder("mud-expansion-panels")
		.AddClass($"mud-expansion-panels-square", Square)
		.AddClass(Class)
	.Build();

	/// <summary>
	/// If true, border-radius is set to 0.
	/// </summary>
	[Parameter]
	[Category(CategoryTypes.ExpansionPanel.Appearance)]
	public bool Square { get; set; }

	/// <summary>
	/// If true, multiple panels can be expanded at the same time.
	/// </summary>
	[Parameter]
	[Category(CategoryTypes.ExpansionPanel.Behavior)]
	public bool MultiExpansion { get; set; }

	/// <summary>
	/// The higher the number, the heavier the drop-shadow. 0 for no shadow.
	/// </summary>
	[Parameter]
	[Category(CategoryTypes.ExpansionPanel.Appearance)]
	public int Elevation { set; get; } = 1;

	/// <summary>
	/// If true, removes vertical padding from all panels' childcontent.
	/// </summary>
	[Parameter]
	[Category(CategoryTypes.ExpansionPanel.Appearance)]
	public bool Dense { get; set; }

	/// <summary>
	/// If true, the left and right padding is removed from all panels' childcontent.
	/// </summary>
	[Parameter]
	[Category(CategoryTypes.ExpansionPanel.Appearance)]
	public bool DisableGutters { get; set; }

	/// <summary>
	/// If true, the borders around each panel will be removed.
	/// </summary>
	[Parameter]
	[Category(CategoryTypes.ExpansionPanel.Appearance)]
	public bool DisableBorders { get; set; }

	/// <summary>
	/// Child content of component.
	/// </summary>
	[Parameter]
	[Category(CategoryTypes.ExpansionPanel.Behavior)]
	public RenderFragment ChildContent { get; set; }

	private List<ExpansionPanel> _panels = new();

	internal void AddPanel(ExpansionPanel panel)
	{
		if (MultiExpansion == false && _panels.Any(p => p.IsExpanded))
		{
			panel.Collapse(update_parent: false);
		}

		panel.NotifyIsExpandedChanged += UpdatePanelsOnPanelsChanged;
		_panels.Add(panel);
	}

	public void RemovePanel(ExpansionPanel panel)
	{
		panel.NotifyIsExpandedChanged -= UpdatePanelsOnPanelsChanged;
		_panels.Remove(panel);
		try
		{
			StateHasChanged();
		}
		catch (InvalidOperationException) { /* this happens on page reload, probably a Blazor bug */ }
	}

	internal void UpdatePanelsOnPanelsChanged(ExpansionPanel panel)
	{
		if (MultiExpansion == false && panel.IsExpanded)
		{
			CollapseAllExcept(panel);
			return;
		}

		UpdateAll();
	}

	public void UpdateAll()
	{
		ExpansionPanel last = null;
		foreach (var panel in _panels)
		{
			if (last != null)
				last.NextPanelExpanded = panel.IsExpanded;
			last = panel;
		}
		StateHasChanged();
	}

	[Obsolete("Use CollapseAllExcept instead.")]
	[ExcludeFromCodeCoverage]
	public void CloseAllExcept(ExpansionPanel panel)
	{
		CollapseAllExcept(panel);
	}

	/// <summary>
	/// Collapses all panels except the given one.
	/// </summary>
	/// <param name="panel">The panel not to collapse.</param>
	public void CollapseAllExcept(ExpansionPanel panel)
	{
		foreach (var p in _panels)
		{
			if (p == panel)
				continue;
			p.Collapse(update_parent: false);
		}
		this.InvokeAsync(UpdateAll);
	}

	/// <summary>
	/// Collapses all panels.
	/// </summary>
	public void CollapseAll()
	{
		foreach (var p in _panels)
		{
			p.Collapse(update_parent: false);
		}
		this.InvokeAsync(UpdateAll);
	}

	/// <summary>
	/// Expands all panels.
	/// </summary>
	public void ExpandAll()
	{
		foreach (var p in _panels)
		{
			p.Expand(update_parent: false);
		}
		this.InvokeAsync(UpdateAll);
	}
}