using System;
using System.Linq.Expressions;

namespace JD.MessageService
{
    public static class MemberNameResolver
    {
        
        public static string ResolveMemberName<T>(Expression<Func<T, object>> expression)
        {
            return ResolveMemberName(expression.Body);
        }

        private static string ResolveMemberName(Expression expression)
        {
            switch (expression.NodeType)
            {
                case ExpressionType.MemberAccess:
                    var memberExpression = (MemberExpression)expression;
                    var supername = ResolveMemberName(memberExpression.Expression);

                    if (string.IsNullOrEmpty(supername))
                    {
                        return memberExpression.Member.Name;
                    }

                    return string.Concat(supername, '.', memberExpression.Member.Name);

                case ExpressionType.Call:
                    var callExpression = (MethodCallExpression)expression;
                    return callExpression.Method.Name;

                case ExpressionType.Convert:
                    var unaryExpression = (UnaryExpression)expression;
                    return ResolveMemberName(unaryExpression.Operand);

                case ExpressionType.Parameter:
                    return string.Empty;

                default:
                    throw new ArgumentException("The expression is not a member access or method call expression");
            }
        }

    }
}