using System;

using System.Collections.Generic;

namespace JSONAPI.Core

{

/// <summary>

/// Default implementation of IModelRegistry

/// </summary>

public class ResourceTypeRegistry : IResourceTypeRegistry

{

private readonly IDictionary<string, IResourceTypeRegistration> _registrationsByName;

private readonly IDictionary<Type, IResourceTypeRegistration> _registrationsByType;

/// <summary>

/// Creates a new ResourceTypeRegistry

/// </summary>

public ResourceTypeRegistry()

{

_registrationsByName = new Dictionary<string, IResourceTypeRegistration>();

_registrationsByType = new Dictionary<Type, IResourceTypeRegistration>();

}

public bool TypeIsRegistered(Type type)

{

var registration = FindRegistrationForType(type);

return registration != null;

}

public IResourceTypeRegistration GetRegistrationForType(Type type)

{

var reg = FindRegistrationForType(type);

if (reg == null)

throw new TypeRegistrationNotFoundException(type);

return reg;

}

public IResourceTypeRegistration GetRegistrationForResourceTypeName(string resourceTypeName)

{

lock (_registrationsByName)

{

IResourceTypeRegistration registration;

if (!_registrationsByName.TryGetValue(resourceTypeName, out registration))

throw new TypeRegistrationNotFoundException(resourceTypeName);

return registration;

}

}

public void AddRegistration(IResourceTypeRegistration registration)

{

lock (_registrationsByType)

{

lock (_registrationsByName)

{

if (_registrationsByType.ContainsKey(registration.Type))

throw new InvalidOperationException(String.Format("The type `{0}` has already been registered.",

registration.Type.FullName));

if (_registrationsByName.ContainsKey(registration.ResourceTypeName))

throw new InvalidOperationException(

String.Format("The resource type name `{0}` has already been registered.",

registration.ResourceTypeName));

_registrationsByType.Add(registration.Type, registration);

_registrationsByName.Add(registration.ResourceTypeName, registration);

}

}

}

private IResourceTypeRegistration FindRegistrationForType(Type type)

{

lock (_registrationsByType)

{

var currentType = type;

while (currentType != null && currentType != typeof(Object))

{

IResourceTypeRegistration registration;

if (_registrationsByType.TryGetValue(currentType, out registration))

return registration;

// This particular type wasn't registered, but maybe the base type was.

currentType = currentType.BaseType;

}

}

return null;

}

}

}