mono/mcs/class/System.Data/System.Data.SqlClient/SqlDataReader.cs

//
// System.Data.SqlClient.SqlDataReader.cs
//
// Author:
//   Rodrigo Moya ([email protected])
//   Daniel Morgan ([email protected])
//   Tim Coleman ([email protected])
//
// (C) Ximian, Inc 2002
// (C) Daniel Morgan 2002
// Copyright (C) Tim Coleman, 2002
//

using Mono.Data.TdsClient.Internal;
using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Data.Common;
using System.Data.SqlTypes;

namespace System.Data.SqlClient {
	public sealed class SqlDataReader : MarshalByRefObject, IEnumerable, IDataReader, IDisposable, IDataRecord
	{
		#region Fields

		int fieldCount;
		bool isClosed;
		int recordsAffected;
		bool moreResults;

		int resultsRead;
		int rowsRead;

		SqlCommand command;
		DataTable schemaTable;

		ArrayList dataTypeNames;
		ArrayList dataTypes;

		#endregion // Fields

		#region Constructors

		internal SqlDataReader (SqlCommand command)
		{
			schemaTable = ConstructSchemaTable ();
			this.resultsRead = 0;
			this.command = command;
			this.fieldCount = 0;
			this.isClosed = false;

			NextResult ();
		}

		#endregion

		#region Properties

		public int Depth {
			get { return 0; }
		}

		public int FieldCount {
			get { return fieldCount; }
		}

		public bool IsClosed {
			get { return isClosed; }
		}

		public object this [int i] {
			get { return GetValue (i); }
		}

		public object this [string name] {
			get { return GetValue (GetOrdinal (name)); }
		}
		
		public int RecordsAffected {
			get { return recordsAffected; }
		}

		#endregion // Properties

		#region Methods

		public void Close()
		{
			isClosed = true;
			command.CloseDataReader (moreResults);
		}

		private static DataTable ConstructSchemaTable ()
		{
			Type booleanType = Type.GetType ("System.Boolean");
			Type stringType = Type.GetType ("System.String");
			Type intType = Type.GetType ("System.Int32");
			Type typeType = Type.GetType ("System.Type");
			Type shortType = Type.GetType ("System.Int16");

			DataTable schemaTable = new DataTable ("SchemaTable");
			schemaTable.Columns.Add ("ColumnName", stringType);
			schemaTable.Columns.Add ("ColumnOrdinal", intType);
			schemaTable.Columns.Add ("ColumnSize", intType);
			schemaTable.Columns.Add ("NumericPrecision", shortType);
			schemaTable.Columns.Add ("NumericScale", shortType);
			schemaTable.Columns.Add ("IsUnique", booleanType);
			schemaTable.Columns.Add ("IsKey", booleanType);
			schemaTable.Columns.Add ("BaseServerName", stringType);
			schemaTable.Columns.Add ("BaseCatalogName", stringType);
			schemaTable.Columns.Add ("BaseColumnName", stringType);
			schemaTable.Columns.Add ("BaseSchemaName", stringType);
			schemaTable.Columns.Add ("BaseTableName", stringType);
			schemaTable.Columns.Add ("DataType", typeType);
			schemaTable.Columns.Add ("AllowDBNull", booleanType);
			schemaTable.Columns.Add ("ProviderType", intType);
			schemaTable.Columns.Add ("IsAliased", booleanType);
			schemaTable.Columns.Add ("IsExpression", booleanType);
			schemaTable.Columns.Add ("IsIdentity", booleanType);
			schemaTable.Columns.Add ("IsAutoIncrement", booleanType);
			schemaTable.Columns.Add ("IsRowVersion", booleanType);
			schemaTable.Columns.Add ("IsHidden", booleanType);
			schemaTable.Columns.Add ("IsLong", booleanType);
			schemaTable.Columns.Add ("IsReadOnly", booleanType);

			return schemaTable;
		}

		public bool GetBoolean (int i)
		{
			object value = GetValue (i);
			if (!(value is bool))
				throw new InvalidCastException ();
			return (bool) value;
		}

		public byte GetByte (int i)
		{
			object value = GetValue (i);
			if (!(value is byte))
				throw new InvalidCastException ();
			return (byte) value;
		}

		public long GetBytes (int i, long dataIndex, byte[] buffer, int bufferIndex, int length)
		{
			object value = GetValue (i);
			if (!(value is byte []))
				throw new InvalidCastException ();
			Array.Copy ((byte []) value, (int) dataIndex, buffer, bufferIndex, length);
			return ((byte []) value).Length - dataIndex;
		}

		[MonoTODO ("Implement GetChar")]
		public char GetChar (int i)
		{
			throw new NotImplementedException ();
		}

		public long GetChars (int i, long dataIndex, char[] buffer, int bufferIndex, int length)
		{
			object value = GetValue (i);
			if (!(value is char []))
				throw new InvalidCastException ();
			Array.Copy ((char []) value, (int) dataIndex, buffer, bufferIndex, length);
			return ((char []) value).Length - dataIndex;
		}

		[MonoTODO ("Implement GetData")]
		public IDataReader GetData (int i)
		{
			throw new NotImplementedException ();
		}

		public string GetDataTypeName (int i)
		{
			return (string) dataTypeNames [i];
		}

		public DateTime GetDateTime (int i)
		{
			object value = GetValue (i);
			if (!(value is DateTime))
				throw new InvalidCastException ();
			return (DateTime) value;
		}

		public decimal GetDecimal (int i)
		{
			object value = GetValue (i);
			if (!(value is TdsBigDecimal))
				throw new InvalidCastException ();
			int[] bits = ((TdsBigDecimal) value).Data;
			if (bits[3] != 0)
				throw new OverflowException ();
			byte scale = ((TdsBigDecimal) value).Scale;
			bool isNegative = ((TdsBigDecimal) value).IsNegative;
			return new Decimal (bits[0], bits[1], bits[2], isNegative, scale);
		}

		private TdsBigDecimal GetDecimalImpl (int i)
		{
			object value = GetValue (i);
			if (!(value is TdsBigDecimal))
				throw new InvalidCastException ();
			return (TdsBigDecimal) value;
		}

		public double GetDouble (int i)
		{
			object value = GetValue (i);
			if (!(value is double))
				throw new InvalidCastException ();
			return (double) value;
		}

		public Type GetFieldType (int i)
		{
			return (Type) schemaTable.Rows[i]["DataType"];
		}

		public float GetFloat (int i)
		{
			object value = GetValue (i);
			if (!(value is float))
				throw new InvalidCastException ();
			return (float) value;
		}

		public Guid GetGuid (int i)
		{
			object value = GetValue (i);
			if (!(value is Guid))
				throw new InvalidCastException ();
			return (Guid) value;
		}

		public short GetInt16 (int i)
		{
			object value = GetValue (i);
			if (!(value is short))
				throw new InvalidCastException ();
			return (short) value;
		}

		public int GetInt32 (int i)
		{
			object value = GetValue (i);
			if (!(value is int))
				throw new InvalidCastException ();
			return (int) value;
		}

		public long GetInt64 (int i)
		{
			object value = GetValue (i);
			if (!(value is long))
				throw new InvalidCastException ();
			return (long) value;
		}

		public string GetName (int i)
		{
			return (string) schemaTable.Rows[i]["ColumnName"];
		}

		[MonoTODO ("Make sure that ordinal is in fact zero-based.")]
		public int GetOrdinal (string name)
		{
			foreach (DataRow schemaRow in schemaTable.Rows)
				if (((string) schemaRow ["ColumnName"]).Equals (name))
					return (int) schemaRow ["ColumnOrdinal"];
			foreach (DataRow schemaRow in schemaTable.Rows)
				if (String.Compare (((string) schemaRow ["ColumnName"]), name, true) == 0)
					return (int) schemaRow ["ColumnOrdinal"];
			throw new IndexOutOfRangeException ();
		}

		public DataTable GetSchemaTable ()
		{
			if (schemaTable.Rows != null && schemaTable.Rows.Count > 0)
				return schemaTable;

			if (!moreResults)
				return null;

			fieldCount = 0;

			dataTypeNames = new ArrayList ();
			dataTypes = new ArrayList ();

			foreach (TdsSchemaInfo schema in command.Tds.Schema) {
				DataRow row = schemaTable.NewRow ();

				// set default values
				row ["AllowDBNull"] = true;
				row ["BaseCatalogName"] = DBNull.Value;
				row ["BaseColumnName"] = DBNull.Value;
				row ["BaseSchemaName"] = DBNull.Value;
				row ["BaseTableName"] = DBNull.Value;
				row ["ColumnName"] = DBNull.Value;
				row ["IsAutoIncrement"] = false;
				row ["IsHidden"] = false;
				row ["IsLong"] = false;
				row ["IsRowVersion"] = false;
				row ["IsUnique"] = false;
				row ["NumericPrecision"] = DBNull.Value;
				row ["NumericScale"] = DBNull.Value;

				switch (schema.ColumnType) {
					case TdsColumnType.Image :
						dataTypeNames.Add ("image");
						row ["ProviderType"] = (int) SqlDbType.Image;
						row ["DataType"] = typeof (byte[]);
						row ["IsLong"] = true;
						break;
					case TdsColumnType.Text :
						dataTypes.Add (typeof (string));
						dataTypeNames.Add ("text");
						row ["ProviderType"] = (int) SqlDbType.Text;
						row ["DataType"] = typeof (string);
						row ["IsLong"] = true;
						break;
					case TdsColumnType.UniqueIdentifier :
						dataTypeNames.Add ("uniqueidentifier");
						row ["ProviderType"] = (int) SqlDbType.UniqueIdentifier;
						row ["DataType"] = typeof (Guid);
						break;
					case TdsColumnType.VarBinary :
					case TdsColumnType.BigVarBinary :
						dataTypeNames.Add ("varbinary");
						row ["ProviderType"] = (int) SqlDbType.VarBinary;
						row ["DataType"] = typeof (byte[]);
						row ["IsLong"] = true;
						break;
					case TdsColumnType.IntN :
					case TdsColumnType.Int4 :
						dataTypeNames.Add ("int");
						row ["ProviderType"] = (int) SqlDbType.Int;
						row ["DataType"] = typeof (int);
						break;
					case TdsColumnType.VarChar :
					case TdsColumnType.BigVarChar :
						dataTypeNames.Add ("varchar");
						row ["ProviderType"] = (int) SqlDbType.VarChar;
						row ["DataType"] = typeof (string);
						break;
					case TdsColumnType.Binary :
					case TdsColumnType.BigBinary :
						dataTypeNames.Add ("binary");
						row ["ProviderType"] = (int) SqlDbType.Binary;
						row ["DataType"] = typeof (byte[]);
						row ["IsLong"] = true;
						break;
					case TdsColumnType.Char :
					case TdsColumnType.BigChar :
						dataTypeNames.Add ("char");
						row ["ProviderType"] = (int) SqlDbType.Char;
						row ["DataType"] = typeof (string);
						break;
					case TdsColumnType.Int1 :
						dataTypeNames.Add ("tinyint");
						row ["ProviderType"] = (int) SqlDbType.TinyInt;
						row ["DataType"] = typeof (byte);
						break;
					case TdsColumnType.Bit :
					case TdsColumnType.BitN :
						dataTypeNames.Add ("bit");
						row ["ProviderType"] = (int) SqlDbType.Bit;
						row ["DataType"] = typeof (bool);
						break;
					case TdsColumnType.Int2 :
						dataTypeNames.Add ("smallint");
						row ["ProviderType"] = (int) SqlDbType.SmallInt;
						row ["DataType"] = typeof (short);
						break;
					case TdsColumnType.DateTime4 :
					case TdsColumnType.DateTime :
					case TdsColumnType.DateTimeN :
						dataTypeNames.Add ("datetime");
						row ["ProviderType"] = (int) SqlDbType.DateTime;
						row ["DataType"] = typeof (DateTime);
						break;
					case TdsColumnType.Real :
						dataTypeNames.Add ("real");
						row ["ProviderType"] = (int) SqlDbType.Real;
						row ["DataType"] = typeof (float);
						break;
					case TdsColumnType.Money :
					case TdsColumnType.MoneyN :
					case TdsColumnType.Money4 :
						dataTypeNames.Add ("money");
						row ["ProviderType"] = (int) SqlDbType.Money;
						row ["DataType"] = typeof (decimal);
						break;
					case TdsColumnType.Float8 :
					case TdsColumnType.FloatN :
						dataTypeNames.Add ("float");
						row ["ProviderType"] = (int) SqlDbType.Float;
						row ["DataType"] = typeof (double);
						break;
					case TdsColumnType.NText :
						dataTypeNames.Add ("ntext");
						row ["ProviderType"] = (int) SqlDbType.NText;
						row ["DataType"] = typeof (string);
						row ["IsLong"] = true;
						break;
					case TdsColumnType.NVarChar :
						dataTypeNames.Add ("nvarchar");
						row ["ProviderType"] = (int) SqlDbType.NVarChar;
						row ["DataType"] = typeof (string);
						break;
					case TdsColumnType.Decimal :
					case TdsColumnType.Numeric :
						dataTypeNames.Add ("decimal");
						row ["ProviderType"] = (int) SqlDbType.Decimal;
						row ["DataType"] = typeof (decimal);
						break;
					case TdsColumnType.NChar :
						dataTypeNames.Add ("nchar");
						row ["ProviderType"] = (int) SqlDbType.Char;
						row ["DataType"] = typeof (string);
						break;
					case TdsColumnType.SmallMoney :
						dataTypeNames.Add ("smallmoney");
						row ["ProviderType"] = (int) SqlDbType.SmallMoney;
						row ["DataType"] = typeof (decimal);
						break;
					default :
						dataTypeNames.Add ("variant");
						row ["ProviderType"] = (int) SqlDbType.Variant;
						row ["DataType"] = typeof (object);
						break;
				}


				// load schema values
				row ["ColumnOrdinal"] = schema.ColumnOrdinal;
				row ["ColumnSize"] = schema.ColumnSize;
				row ["AllowDBNull"] = schema.AllowDBNull;
				row ["IsExpression"] = schema.IsExpression;
				row ["IsIdentity"] = schema.IsIdentity;
				row ["IsReadOnly"] = schema.IsReadOnly;
				row ["IsKey"] = schema.IsKey;

				if (schema.BaseColumnName != null)
					row ["BaseColumnName"] = schema.BaseColumnName;

				if (schema.ColumnName != null)
					row ["ColumnName"] = schema.ColumnName;

				if (schema.BaseTableName != null)
					row ["BaseTableName"] = schema.BaseTableName;

				if (schema.NumericScale != 0)
					row ["NumericPrecision"] = schema.NumericPrecision;

				if (schema.NumericScale == 0)
					row ["NumericScale"] = schema.NumericScale;

				schemaTable.Rows.Add (row);

				fieldCount += 1;
			}
			return schemaTable;
		}		

		public SqlBinary GetSqlBinary (int i)
		{
			throw new NotImplementedException ();
		}

		public SqlBoolean GetSqlBoolean (int i) 
		{
			object value = GetValue (i);
			if (value == null)
				return SqlBoolean.Null;
			if (!(value is bool))
				throw new InvalidCastException ();
			return (bool) value;
		}

		public SqlByte GetSqlByte (int i)
		{
			object value = GetValue (i);
			if (value == null)
				return SqlByte.Null;
			if (!(value is byte))
				throw new InvalidCastException ();
			return (byte) value;
		}

		public SqlDateTime GetSqlDateTime (int i)
		{
			object value = GetValue (i);
			if (value == null)
				return SqlDateTime.Null;
			if (!(value is DateTime))
				throw new InvalidCastException ();
			return (DateTime) value;
		}

		public SqlDecimal GetSqlDecimal (int i)
		{
			object value = GetValue (i);
			if (value == null)
				return SqlDecimal.Null;
			if (!(value is TdsBigDecimal))
				throw new InvalidCastException ();
			return SqlDecimal.FromTdsBigDecimal ((TdsBigDecimal) value);
		}

		public SqlDouble GetSqlDouble (int i)
		{
			object value = GetValue (i);
			if (value == null)
				return SqlDouble.Null;
			if (!(value is double))
				throw new InvalidCastException ();
			return (double) value;
		}

		public SqlGuid GetSqlGuid (int i)
		{
			object value = GetValue (i);
			if (value == null)
				return SqlGuid.Null;
			if (!(value is Guid))
				throw new InvalidCastException ();
			return (Guid) value;
		}

		public SqlInt16 GetSqlInt16 (int i)
		{
			object value = GetValue (i);
			if (value == null)
				return SqlInt16.Null;
			if (!(value is short))
				throw new InvalidCastException ();
			return (short) value;
		}

		public SqlInt32 GetSqlInt32 (int i)
		{
			object value = GetValue (i);
			if (value == null)
				return SqlInt32.Null;
			if (!(value is int))
				throw new InvalidCastException ();
			return (int) value;
		}

		public SqlInt64 GetSqlInt64 (int i)
		{
			object value = GetValue (i);
			if (value == null)
				return SqlInt64.Null;
			if (!(value is long))
				throw new InvalidCastException ();
			return (long) value;
		}

		public SqlMoney GetSqlMoney (int i)
		{
			object value = GetValue (i);
			if (value == null)
				return SqlMoney.Null;
			if (!(value is TdsBigDecimal))
				throw new InvalidCastException ();
			return (SqlMoney) (SqlDecimal) value;
		}

		public SqlSingle GetSqlSingle (int i)
		{
			object value = GetValue (i);
			if (value == null)
				return SqlSingle.Null;
			if (!(value is float))
				throw new InvalidCastException ();
			return (float) value;
		}

		public SqlString GetSqlString (int i)
		{
			object value = GetValue (i);
			if (value == null)
				return SqlString.Null;
			if (!(value is string))
				throw new InvalidCastException ();
			return (string) value;
		}

		[MonoTODO ("Implement GetSqlValue")]
		public object GetSqlValue (int i)
		{
			object value = GetValue (i);
			if (value == null)
				return DBNull.Value; 
			throw new NotImplementedException ();
		}

		[MonoTODO ("Implement GetSqlValues")]
		public int GetSqlValues (object[] values)
		{
			throw new NotImplementedException ();
		}

		public string GetString (int i)
		{
			object value = GetValue (i);
			if (!(value is string))
				throw new InvalidCastException ();
			return (string) value;
		}

		public object GetValue (int i)
		{
			return command.Tds.ColumnValues[i];
		}

		public int GetValues (object[] values)
		{
			int len = values.Length;
			command.Tds.ColumnValues.CopyTo (0, values, 0, len);
			return (len > FieldCount ? len : FieldCount);
		}

		[MonoTODO ("Implement Dispose().  Determine what must be disposed of.")]
		void IDisposable.Dispose ()
		{
			throw new NotImplementedException ();
		}

		IEnumerator IEnumerable.GetEnumerator ()
		{
			return new DbEnumerator (this);
		}

		public bool IsDBNull (int i)
		{
			return GetValue (i) == null;
		}

		public bool NextResult ()
		{
			if ((command.CommandBehavior & CommandBehavior.SingleResult) != 0 && resultsRead > 0)
				return false;
			if (command.Tds.DoneProc)
				return false;

			schemaTable.Rows.Clear ();

			moreResults = command.Tds.NextResult ();
			GetSchemaTable ();

			rowsRead = 0;
			resultsRead += 1;
			return moreResults;
		}

		public bool Read ()
		{
			if ((command.CommandBehavior & CommandBehavior.SingleRow) != 0 && rowsRead > 0)
				return false;
			if ((command.CommandBehavior & CommandBehavior.SchemaOnly) != 0)
				return false;
			if (!moreResults)
				return false;

			bool result = command.Tds.NextRow ();

			rowsRead += 1;

			return result;
		}

		#endregion // Methods
	}
}