using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

namespace Simple.Data

{

using System.Dynamic;

using System.Reflection;

internal class AdapterMethodDynamicInvoker

{

private readonly Adapter _adapter;

public AdapterMethodDynamicInvoker(Adapter adapter)

{

_adapter = adapter;

}

public bool TryInvokeMember(InvokeMemberBinder binder, object[] args, out object result)

{

var adapterMethods = _adapter.GetType().GetMethods().Where(m => m.Name == binder.Name).ToList();

foreach (var method in adapterMethods)

{

var parameters = method.GetParameters().ToArray();

if (parameters.Any(p => p.RawDefaultValue != DBNull.Value) && binder.CallInfo.ArgumentNames.Any(s => !string.IsNullOrWhiteSpace(s)))

{

if (TryInvokeMemberWithNamedParameters(binder, args, out result, method, parameters))

{

return true;

}

}

else

{

if (AreCompatible(parameters, args))

{

result = method.Invoke(_adapter, args);

return true;

}

}

}

result = null;

return false;

}

private bool TryInvokeMemberWithNamedParameters(InvokeMemberBinder binder, object[] args, out object result,

MethodInfo method, ParameterInfo[] parameters)

{

var fixedArgs = new List<object>();

for (int i = 0; i < parameters.Length; i++)

{

if (parameters[i].RawDefaultValue == DBNull.Value)

{

fixedArgs.Add(args[i]);

}

else

{

var index = binder.CallInfo.ArgumentNames.IndexOf(parameters[i].Name);

if (index > -1)

{

if (!parameters[i].ParameterType.IsInstanceOfType(args[index]))

{

result = null;

return false;

}

}

else

{

fixedArgs.Add(parameters[i].RawDefaultValue);

}

}

}

result = method.Invoke(_adapter, fixedArgs.ToArray());

return true;

}

private static bool AreCompatible(IList<ParameterInfo> parameters, IList<object> args)

{

if (parameters.Count != args.Count) return false;

for (int i = 0; i < parameters.Count; i++)

{

if (ReferenceEquals(args[i], null)) return !parameters[i].ParameterType.IsValueType;

if (!parameters[i].ParameterType.IsInstanceOfType(args[i])) return false;

}

return true;

}

}

}