Abstract Data Access Layer Design

using System;
using System.Collections.Generic;
using System.Text;
using System.Reflection;

namespace XPeriment.Persistence.PersistentObjects
{
    public class ReflectionUtility
    {
        public static bool IsNulable(PropertyInfo pi)
        {
            object[] attributes = pi.GetCustomAttributes(typeof(NullsAllowed), true);
            if (attributes.Length > 0)
                return true;
            return false;
        }

        public static string GetDBField(PropertyInfo pi)
        {
            object[] attributes = pi.GetCustomAttributes(typeof(MapToAttribute), true);
            if (attributes.Length > 0)
            {
                MapToAttribute mapto = (MapToAttribute)attributes[0];
                return mapto.DBReference;
            }
            return pi.Name;
        }

        public static Dictionary<string, object> GetNameMappings(object obj)
        {
            Dictionary<string, object> retval = new Dictionary<string, object>();
            Type objtype = obj.GetType();
            PropertyInfo[] props = objtype.GetProperties();
            foreach (PropertyInfo pi in props)
            {                
                if (!MarkedAsPrimaryKey(pi) && !MarkedAsIgnoreMapping(pi))
                {
                    object[] attributes = pi.GetCustomAttributes(typeof(MapToAttribute), true);
                    if (attributes.Length > 0)
                    {
                        MapToAttribute mapto = (MapToAttribute)attributes[0];
                        retval.Add(mapto.DBReference, pi.GetValue(obj, null));
                    }
                    else
                    {
                        retval.Add(pi.Name, pi.GetValue(obj, null));
                    }
                }
            }
            return retval;
        }

        public static Dictionary<string, object> GetValueMappings(object obj)
        {
            Dictionary<string, object> retval = new Dictionary<string, object>();
            Type objtype = obj.GetType();
            PropertyInfo[] props = objtype.GetProperties();
            foreach (PropertyInfo pi in props)
            {
                MapToAttribute[] attributes = (MapToAttribute[])pi.GetCustomAttributes(typeof(MapToAttribute), true);
                if (attributes.Length > 0)
                {
                    MapToAttribute mapto = attributes[0];
                    retval.Add(mapto.DBReference, pi.GetValue(obj, null));
                }
                else
                {
                    if (!ReflectionUtility.MarkedAsIgnoreMapping(pi))
                        retval.Add(pi.Name, pi.GetValue(obj, null));
                }
            }
            return retval;
        }

        public static string GetTargetTable(object obj)
        {
            Type t = obj.GetType();
            MapToAttribute map = (MapToAttribute)t.GetCustomAttributes(typeof(MapToAttribute), true)[0];
            return map.DBReference;
        }

        public static bool MarkedAsPrimaryKey(PropertyInfo pi)
        {
            object[] attributes = pi.GetCustomAttributes(typeof(PrimaryKeyAttribute),true);
            if (attributes.Length > 0)
                return true;
            return false;
        }

        public static bool MarkedAsForaignKey(PropertyInfo pi)
        {
            object[] attributes = pi.GetCustomAttributes(typeof(ForaignKey), true);
            if (attributes.Length > 0)
                return true;
            return false;
        }


        public static bool MarkedAsIgnoreMapping(PropertyInfo pi)
        {
            object[] attributes = pi.GetCustomAttributes(typeof(IgnoreMappingAttribute), true);
            if (attributes.Length > 0)
                return true;
            return false;
        }


        public static string GetPrimaryKeyField(object obj)
        {
            Type objtype = obj.GetType();
            PropertyInfo[] props = objtype.GetProperties();
            foreach (PropertyInfo pi in props)
            {
                PrimaryKeyAttribute[] attributes = (PrimaryKeyAttribute[])pi.GetCustomAttributes(typeof(PrimaryKeyAttribute), true);
                if (attributes.Length > 0)
                {
                    PrimaryKeyAttribute pk = attributes[0];
                    return GetDBField(pi);
                }
            }
            throw new Exception("Object of type '"+objtype.Name+"' has no primary keys defined");
        }

        public static object GetPrimaryKeyValue(object obj)
        {
            return "";
        }

        public static void SetValue(object obj, Dictionary<string, object> mappings)
        {

        }

    }
}