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

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.Exceptions;

using ScriptEngine.Machine;

namespace OneScript.Values

{

public class PropertyValueReference : IValueReference

{

private readonly IRuntimeContextInstance _context;

private readonly int _contextPropertyNumber;

public PropertyValueReference(IRuntimeContextInstance context, string propertyName)

{

_context = context;

_contextPropertyNumber = context.GetPropertyNumber(propertyName);

}

public PropertyValueReference(IRuntimeContextInstance context, int propertyId)

{

_context = context;

_contextPropertyNumber = propertyId;

}

public bool Equals(IValueReference other)

{

if (ReferenceEquals(null, other)) return false;

if (ReferenceEquals(this, other)) return true;

if (!(other is PropertyValueReference prop))

return false;

return _context.Equals(prop._context) && _contextPropertyNumber == prop._contextPropertyNumber;

}

public override bool Equals(object obj)

{

if (ReferenceEquals(null, obj)) return false;

if (ReferenceEquals(this, obj)) return true;

return obj.GetType() == this.GetType() && Equals((PropertyValueReference)obj);

}

public override int GetHashCode()

{

return HashCode.Combine(_context, _contextPropertyNumber);

}

public IValue Value

{

get

{

if (_context.IsPropReadable(_contextPropertyNumber))

return (BslValue)_context.GetPropValue(_contextPropertyNumber);

throw PropertyAccessException.PropIsNotReadableException(PropertyName());

}

set

{

if(_context.IsPropWritable(_contextPropertyNumber))

_context.SetPropValue(_contextPropertyNumber, value);

else

throw PropertyAccessException.PropIsNotWritableException(PropertyName());

}

}

private string PropertyName() => _context.GetPropertyInfo(_contextPropertyNumber).Name;

}

}