/*----------------------------------------------------------

This Source Code Form is subject to the terms of the

Mozilla Public License, v.2.0. If a copy of the MPL

was not distributed with this file, You can obtain one

at http://mozilla.org/MPL/2.0/.

----------------------------------------------------------*/

using System;

using OneScript.Contexts;

using OneScript.Compilation.Binding;

namespace ScriptEngine.Machine

{

public struct ModuleSymbolBinding : IEquatable<ModuleSymbolBinding>

{

public IAttachableContext Target { get; set; }

public int MemberNumber { get; set; }

public ScopeBindingKind Kind { get; set; }

public int ScopeIndex { get; set; }

internal IAttachableContext ResolveTarget(ExecutionFrame frame)

{

return Kind switch

{

ScopeBindingKind.FrameScope => ResolveFrameScope(frame),

ScopeBindingKind.ThisScope => frame.ThisScope,

_ => Target

};

}

private IAttachableContext ResolveFrameScope(ExecutionFrame frame)

{

if (frame?.Scopes == null)

throw new InvalidOperationException("Frame scopes are not available");

if (ScopeIndex < 0 || ScopeIndex >= frame.Scopes.Count)

throw new InvalidOperationException($"Invalid scope index {ScopeIndex}");

return frame.Scopes[ScopeIndex];

}

public bool Equals(ModuleSymbolBinding other)

{

return ReferenceEquals(Target, other.Target)

&& MemberNumber == other.MemberNumber

&& Kind == other.Kind

&& ScopeIndex == other.ScopeIndex;

}

public override bool Equals(object obj)

{

return obj is ModuleSymbolBinding other && Equals(other);

}

public override int GetHashCode()

{

return HashCode.Combine(Target, MemberNumber, Kind, ScopeIndex);

}

}

}