// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.

using System;

namespace Microsoft.CodeAnalysis;

[Flags]
internal enum TypeOrNamespaceUsageInfo
{
    /// <summary>
    /// Represents default value indicating no usage.
    /// </summary>
    None = 0x0,

    /// <summary>
    /// Represents a reference to a namespace or type on the left side of a dotted name (qualified name or member access).
    /// For example, 'NS' in <code>NS.Type x = new NS.Type();</code> or <code>NS.Type.StaticMethod();</code> or 
    /// 'Type' in <code>Type.NestedType x = new Type.NestedType();</code> or <code>Type.StaticMethod();</code>
    /// </summary>
    Qualified = 0x01,

    /// <summary>
    /// Represents a generic type argument reference.
    /// For example, 'Type' in <code>Generic{Type} x = ...;</code> or <code>class Derived : Base{Type} { }</code>
    /// </summary>
    TypeArgument = 0x02,

    /// <summary>
    /// Represents a type parameter constraint that is a type.
    /// For example, 'Type' in <code>class Derived{T} where T : Type { }</code>
    /// </summary>
    TypeConstraint = 0x04,

    /// <summary>
    /// Represents a base type or interface reference in the base list of a named type.
    /// For example, 'Base' in <code>class Derived : Base { }</code>.
    /// </summary>
    Base = 0x08,

    /// <summary>
    /// Represents a reference to a type whose instance is being created.
    /// For example, 'C' in <code>var x = new C();</code>, where 'C' is a named type.
    /// </summary>
    ObjectCreation = 0x10,

    /// <summary>
    /// Represents a reference to a namespace or type within a using or imports directive.
    /// For example, <code>using NS;</code> or <code>using static NS.Extensions</code> or <code>using Alias = MyType</code>.
    /// </summary>
    Import = 0x20,

    /// <summary>
    /// Represents a reference to a namespace name in a namespace declaration context.
    /// For example, 'N1' or <code>namespaces N1.N2 { }</code>.
    /// </summary>
    NamespaceDeclaration = 0x40,
}