using System;

using System.Collections.Generic;

using System.Data.SqlTypes;

using System.Dynamic;

using System.Linq;

using System.Reflection;

using System.Text.RegularExpressions;

namespace Poco.Sql.NetCore

{

public class ValuesObject

{

private static readonly SqlDateTime _smallDateTimeMinValue = new SqlDateTime(new DateTime(1900, 01, 01, 00, 00, 00));

public static object Create(params object[] args)

{

dynamic obj = new ExpandoObject();

List<string> sqlParams = GetPramsFromSqlString(args);

int startPos = sqlParams == null ? 0 : 1; // if we have sqlParams that means that the first agrument is an sql string

// loop over all objects that were sent for merging

for (int i = startPos; i < args.Length; i++)

{

// get an object and make sure it's valid

object currentObj = args[i];

if (currentObj == null) continue;

IDictionary<string, object> objDic = (IDictionary<string, object>) obj;

// loop over all elements of current object

IEnumerable<PropertyInfo> propertyInfos = currentObj.GetType().GetRuntimeProperties();

foreach (

PropertyInfo propertyInfo in

propertyInfos.Where(

p =>

p.PropertyType.GetTypeInfo().IsEnum ||

(p.PropertyType.FullName.StartsWith("System") &&

!p.PropertyType.FullName.StartsWith("System.Collections"))))

// only loop on objects that are not custom class

{

if (objDic.ContainsKey(propertyInfo.Name))

continue; // same key can't be added twice (first key found will be used)

if (sqlParams == null || sqlParams.Contains(propertyInfo.Name))

{

var val = propertyInfo.GetValue(currentObj);

if (propertyInfo.PropertyType == typeof (DateTime) && (DateTime) val == DateTime.MinValue)

val = (DateTime) System.Data.SqlTypes.SqlDateTime.MinValue;

objDic.Add(propertyInfo.Name, val);

}

}

}

return (object)obj;

}

private static object getDefaultValue(Type t)

{

if (t == typeof(DateTime))

return DateTime.MinValue;

else if (t.GetTypeInfo().IsValueType)

return Activator.CreateInstance(t);

return null;

}

private static List<string> GetPramsFromSqlString(object[] args)

{

List<string> sqlParams = null;

if (args.Length > 1 && args[0] is String)

{

sqlParams = new List<string>();

string sql = args[0].ToString();

Regex regex = new Regex(@"(?<=@)([\w\-]+)");

var matches = regex.Matches(sql);

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

{

var val = matches[i].Value;

if (!sqlParams.Contains(val))

sqlParams.Add(matches[i].Value);

}

}

return sqlParams;

}

}

}