namespace BizHawk.Analyzers;

using Microsoft.CodeAnalysis;
using Microsoft.CodeAnalysis.CSharp;
using Microsoft.CodeAnalysis.CSharp.Syntax;

public static class RoslynUtils
{
	public static SyntaxNode? EnclosingTypeDeclarationSyntax(this CSharpSyntaxNode node)
	{
		var parent = node.Parent;
		while (parent is not (null or TypeDeclarationSyntax)) parent = parent.Parent;
		return parent;
	}

	private static ITypeSymbol? GetThrownExceptionType(this SemanticModel model, ExpressionSyntax exprSyn)
		=> exprSyn is ObjectCreationExpressionSyntax
			? model.GetTypeInfo(exprSyn).Type
			: null; // code reads `throw <something weird>`

	public static ITypeSymbol? GetThrownExceptionType(this SemanticModel model, ThrowExpressionSyntax tes)
		=> model.GetThrownExceptionType(tes.Expression);

	public static ITypeSymbol? GetThrownExceptionType(this SemanticModel model, ThrowStatementSyntax tss)
		=> model.GetThrownExceptionType(tss.Expression!);

	public static bool Matches(this ISymbol expected, ISymbol? actual)
		=> SymbolEqualityComparer.Default.Equals(expected, actual);
}