using Microsoft.Maui.ApplicationModel;
using Microsoft.UI.Xaml;
using Microsoft.UI.Xaml.Automation.Peers;
using Microsoft.UI.Xaml.Media;
 
namespace Microsoft.Maui.Accessibility
{
	partial class SemanticScreenReaderImplementation : ISemanticScreenReader
	{
		public void Announce(string text)
		{
			if (WindowStateManager.Default.GetActiveWindow() is not Window window)
				return;
 
			var peer = FindAutomationPeer(window.Content);
 
			// This GUID correlates to the internal messages used by UIA to perform an announce
			// You can extract it  by using accessibility insights to monitor UIA events
			// If you're curious how this works then do a google search for the GUID
			peer.RaiseNotificationEvent(
				AutomationNotificationKind.ActionAborted,
				AutomationNotificationProcessing.ImportantMostRecent,
				text,
				"270FA098-C644-40A2-A0BE-A9BEA1222A1E");
		}
 
		// This isn't great but it's the only way I've found to announce with WinUI.
		// You have to locate a control that has an automation peer and then use that
		// to perform the announce operation. This creates scenarios where the
		// screen might not have any automation peers on it to use but in those cases
		// you really shouldn't be using the announce API
		static AutomationPeer FindAutomationPeer(DependencyObject depObj)
		{
			if (depObj != null)
			{
				for (int i = 0; i < VisualTreeHelper.GetChildrenCount(depObj); i++)
				{
					DependencyObject child = VisualTreeHelper.GetChild(depObj, i);
					if (child is UIElement element && FrameworkElementAutomationPeer.FromElement(element) != null)
					{
						return FrameworkElementAutomationPeer.FromElement(element);
					}
 
					var childItem = FindAutomationPeer(child);
					if (childItem != null)
						return childItem;
				}
			}
			return null;
		}
	}
}