/*
  Copyright (c) 2002, 2015, Oracle and/or its affiliates. All rights reserved.

  The MySQL Connector/J is licensed under the terms of the GPLv2
  <http://www.gnu.org/licenses/old-licenses/gpl-2.0.html>, like most MySQL Connectors.
  There are special exceptions to the terms and conditions of the GPLv2 as it is applied to
  this software, see the FOSS License Exception
  <http://www.mysql.com/about/legal/licensing/foss-exception.html>.

  This program is free software; you can redistribute it and/or modify it under the terms
  of the GNU General Public License as published by the Free Software Foundation; version 2
  of the License.

  This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
  without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  See the GNU General Public License for more details.

  You should have received a copy of the GNU General Public License along with this
  program; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth
  Floor, Boston, MA 02110-1301  USA

 */

package com.mysql.jdbc;

import java.io.InputStream;
import java.io.Reader;
import java.io.UnsupportedEncodingException;
import java.sql.NClob;
import java.sql.RowId;
import java.sql.SQLException;
import java.sql.SQLXML;
import java.sql.Struct;
import java.sql.SQLFeatureNotSupportedException;

import com.mysql.jdbc.Connection;
import com.mysql.jdbc.Field;
import com.mysql.jdbc.NotUpdatable;
import com.mysql.jdbc.ResultSetImpl;
import com.mysql.jdbc.RowData;
import com.mysql.jdbc.SQLError;
import com.mysql.jdbc.Statement;

public class JDBC4ResultSet extends ResultSetImpl {

    public JDBC4ResultSet(long updateCount, long updateID, MySQLConnection conn, StatementImpl creatorStmt) {
        super(updateCount, updateID, conn, creatorStmt);
    }

    public JDBC4ResultSet(String catalog, Field[] fields, RowData tuples, MySQLConnection conn, StatementImpl creatorStmt) throws SQLException {
        super(catalog, fields, tuples, conn, creatorStmt);
    }

    /**
     * JDBC 4.0
     * 
     * <p>
     * Get the value of a column in the current row as a java.io.Reader.
     * </p>
     * 
     * @param columnIndex
     *            the column to get the value from
     * 
     * @return the value in the column as a java.io.Reader.
     * 
     * @throws SQLException
     *             if an error occurs
     */
    public Reader getNCharacterStream(int columnIndex) throws SQLException {
        checkColumnBounds(columnIndex);

        String fieldEncoding = this.fields[columnIndex - 1].getEncoding();
        if (fieldEncoding == null || !fieldEncoding.equals("UTF-8")) {
            throw new SQLException("Can not call getNCharacterStream() when field's charset isn't UTF-8");
        }
        return getCharacterStream(columnIndex);
    }

    /**
     * JDBC 4.0
     * 
     * <p>
     * Get the value of a column in the current row as a java.io.Reader.
     * </p>
     * 
     * @param columnName
     *            the column name to retrieve the value from
     * 
     * @return the value as a java.io.Reader
     * 
     * @throws SQLException
     *             if an error occurs
     */
    public Reader getNCharacterStream(String columnName) throws SQLException {
        return getNCharacterStream(findColumn(columnName));
    }

    /**
     * JDBC 4.0 Get a NCLOB column.
     * 
     * @param i
     *            the first column is 1, the second is 2, ...
     * 
     * @return an object representing a NCLOB
     * 
     * @throws SQLException
     *             if an error occurs
     */
    public NClob getNClob(int columnIndex) throws SQLException {
        checkColumnBounds(columnIndex);

        String fieldEncoding = this.fields[columnIndex - 1].getEncoding();
        if (fieldEncoding == null || !fieldEncoding.equals("UTF-8")) {
            throw new SQLException("Can not call getNClob() when field's charset isn't UTF-8");
        }
        if (!this.isBinaryEncoded) {
            String asString = getStringForNClob(columnIndex);

            if (asString == null) {
                return null;
            }

            return new com.mysql.jdbc.JDBC4NClob(asString, getExceptionInterceptor());
        }

        return getNativeNClob(columnIndex);
    }

    /**
     * JDBC 4.0 Get a NCLOB column.
     * 
     * @param colName
     *            the column name
     * 
     * @return an object representing a NCLOB
     * 
     * @throws SQLException
     *             if an error occurs
     */
    public NClob getNClob(String columnName) throws SQLException {
        return getNClob(findColumn(columnName));
    }

    /**
     * JDBC 4.0 Get a NCLOB column.
     * 
     * @param columnIndex
     *            the first column is 1, the second is 2, ...
     * 
     * @return an object representing a NCLOB
     * 
     * @throws SQLException
     *             if an error occurs
     */
    protected java.sql.NClob getNativeNClob(int columnIndex) throws SQLException {
        String stringVal = getStringForNClob(columnIndex);

        if (stringVal == null) {
            return null;
        }

        return getNClobFromString(stringVal, columnIndex);
    }

    private String getStringForNClob(int columnIndex) throws SQLException {
        String asString = null;

        String forcedEncoding = "UTF-8";

        try {
            byte[] asBytes = null;

            if (!this.isBinaryEncoded) {
                asBytes = getBytes(columnIndex);
            } else {
                asBytes = getNativeBytes(columnIndex, true);
            }

            if (asBytes != null) {
                asString = new String(asBytes, forcedEncoding);
            }
        } catch (UnsupportedEncodingException uee) {
            throw SQLError.createSQLException("Unsupported character encoding " + forcedEncoding, SQLError.SQL_STATE_ILLEGAL_ARGUMENT,
                    getExceptionInterceptor());
        }

        return asString;
    }

    private final java.sql.NClob getNClobFromString(String stringVal, int columnIndex) throws SQLException {
        return new com.mysql.jdbc.JDBC4NClob(stringVal, getExceptionInterceptor());
    }

    /**
     * JDBC 4.0
     * 
     * Get the value of a column in the current row as a Java String
     * 
     * @param columnIndex
     *            the first column is 1, the second is 2...
     * 
     * @return the column value, null for SQL NULL
     * 
     * @exception SQLException
     *                if a database access error occurs
     */
    public String getNString(int columnIndex) throws SQLException {
        checkColumnBounds(columnIndex);

        String fieldEncoding = this.fields[columnIndex - 1].getEncoding();
        if (fieldEncoding == null || !fieldEncoding.equals("UTF-8")) {
            throw new SQLException("Can not call getNString() when field's charset isn't UTF-8");
        }
        return getString(columnIndex);
    }

    /**
     * JDBC 4.0
     * 
     * The following routines simply convert the columnName into a columnIndex
     * and then call the appropriate routine above.
     * 
     * @param columnName
     *            is the SQL name of the column
     * 
     * @return the column value
     * 
     * @exception SQLException
     *                if a database access error occurs
     */
    public String getNString(String columnName) throws SQLException {
        return getNString(findColumn(columnName));
    }

    /**
     * JDBC 4.0 Update a column with a character stream value. The updateXXX()
     * methods are used to update column values in the current row, or the
     * insert row. The updateXXX() methods do not update the underlying
     * database, instead the updateRow() or insertRow() methods are called to
     * update the database.
     * 
     * @param columnIndex
     *            the first column is 1, the second is 2, ...
     * @param x
     *            the new column value
     * @param length
     *            the length of the stream
     * 
     * @exception SQLException
     *                if a database-access error occurs
     * @throws NotUpdatable
     */
    public void updateNCharacterStream(int columnIndex, Reader x, int length) throws SQLException {
        throw new NotUpdatable();
    }

    /**
     * JDBC 4.0 Update a column with a character stream value. The updateXXX()
     * methods are used to update column values in the current row, or the
     * insert row. The updateXXX() methods do not update the underlying
     * database, instead the updateRow() or insertRow() methods are called to
     * update the database.
     * 
     * @param columnName
     *            the name of the column
     * @param reader
     *            the stream to update the column with
     * @param length
     *            of the stream
     * 
     * @throws SQLException
     *             if a database-access error occurs
     */
    public void updateNCharacterStream(String columnName, Reader reader, int length) throws SQLException {
        updateNCharacterStream(findColumn(columnName), reader, length);
    }

    /**
     * @see ResultSet#updateNClob(String, NClob)
     */
    public void updateNClob(String columnName, NClob nClob) throws SQLException {
        updateNClob(findColumn(columnName), nClob);
    }

    public void updateRowId(int columnIndex, RowId x) throws SQLException {
        throw new NotUpdatable();
    }

    public void updateRowId(String columnName, RowId x) throws SQLException {
        updateRowId(findColumn(columnName), x);
    }

    public int getHoldability() throws SQLException {
        throw SQLError.createSQLFeatureNotSupportedException();
    }

    public RowId getRowId(int columnIndex) throws SQLException {
        throw SQLError.createSQLFeatureNotSupportedException();
    }

    public RowId getRowId(String columnLabel) throws SQLException {
        return getRowId(findColumn(columnLabel));
    }

    public SQLXML getSQLXML(int columnIndex) throws SQLException {
        checkColumnBounds(columnIndex);

        return new JDBC4MysqlSQLXML(this, columnIndex, getExceptionInterceptor());
    }

    public SQLXML getSQLXML(String columnLabel) throws SQLException {
        return getSQLXML(findColumn(columnLabel));
    }

    public void updateAsciiStream(int columnIndex, InputStream x) throws SQLException {
        throw new NotUpdatable();

    }

    public void updateAsciiStream(String columnLabel, InputStream x) throws SQLException {
        updateAsciiStream(findColumn(columnLabel), x);

    }

    public void updateAsciiStream(int columnIndex, InputStream x, long length) throws SQLException {
        throw new NotUpdatable();

    }

    public void updateAsciiStream(String columnLabel, InputStream x, long length) throws SQLException {
        updateAsciiStream(findColumn(columnLabel), x, length);
    }

    public void updateBinaryStream(int columnIndex, InputStream x) throws SQLException {
        throw new NotUpdatable();

    }

    public void updateBinaryStream(String columnLabel, InputStream x) throws SQLException {
        updateBinaryStream(findColumn(columnLabel), x);
    }

    public void updateBinaryStream(int columnIndex, InputStream x, long length) throws SQLException {
        throw new NotUpdatable();

    }

    public void updateBinaryStream(String columnLabel, InputStream x, long length) throws SQLException {
        updateBinaryStream(findColumn(columnLabel), x, length);
    }

    public void updateBlob(int columnIndex, InputStream inputStream) throws SQLException {
        throw new NotUpdatable();
    }

    public void updateBlob(String columnLabel, InputStream inputStream) throws SQLException {
        updateBlob(findColumn(columnLabel), inputStream);
    }

    public void updateBlob(int columnIndex, InputStream inputStream, long length) throws SQLException {
        throw new NotUpdatable();

    }

    public void updateBlob(String columnLabel, InputStream inputStream, long length) throws SQLException {
        updateBlob(findColumn(columnLabel), inputStream, length);
    }

    public void updateCharacterStream(int columnIndex, Reader x) throws SQLException {
        throw new NotUpdatable();

    }

    public void updateCharacterStream(String columnLabel, Reader reader) throws SQLException {
        updateCharacterStream(findColumn(columnLabel), reader);
    }

    public void updateCharacterStream(int columnIndex, Reader x, long length) throws SQLException {
        throw new NotUpdatable();

    }

    public void updateCharacterStream(String columnLabel, Reader reader, long length) throws SQLException {
        updateCharacterStream(findColumn(columnLabel), reader, length);
    }

    public void updateClob(int columnIndex, Reader reader) throws SQLException {
        throw new NotUpdatable();

    }

    public void updateClob(String columnLabel, Reader reader) throws SQLException {
        updateClob(findColumn(columnLabel), reader);
    }

    public void updateClob(int columnIndex, Reader reader, long length) throws SQLException {
        throw new NotUpdatable();

    }

    public void updateClob(String columnLabel, Reader reader, long length) throws SQLException {
        updateClob(findColumn(columnLabel), reader, length);
    }

    public void updateNCharacterStream(int columnIndex, Reader x) throws SQLException {
        throw new NotUpdatable();

    }

    public void updateNCharacterStream(String columnLabel, Reader reader) throws SQLException {
        updateNCharacterStream(findColumn(columnLabel), reader);

    }

    public void updateNCharacterStream(int columnIndex, Reader x, long length) throws SQLException {
        throw new NotUpdatable();

    }

    public void updateNCharacterStream(String columnLabel, Reader reader, long length) throws SQLException {
        updateNCharacterStream(findColumn(columnLabel), reader, length);
    }

    public void updateNClob(int columnIndex, NClob nClob) throws SQLException {
        throw new NotUpdatable();

    }

    public void updateNClob(int columnIndex, Reader reader) throws SQLException {
        throw new NotUpdatable();

    }

    public void updateNClob(String columnLabel, Reader reader) throws SQLException {
        updateNClob(findColumn(columnLabel), reader);

    }

    public void updateNClob(int columnIndex, Reader reader, long length) throws SQLException {
        throw new NotUpdatable();
    }

    public void updateNClob(String columnLabel, Reader reader, long length) throws SQLException {
        updateNClob(findColumn(columnLabel), reader, length);
    }

    public void updateNString(int columnIndex, String nString) throws SQLException {
        throw new NotUpdatable();

    }

    public void updateNString(String columnLabel, String nString) throws SQLException {
        updateNString(findColumn(columnLabel), nString);
    }

    public void updateSQLXML(int columnIndex, SQLXML xmlObject) throws SQLException {
        throw new NotUpdatable();

    }

    public void updateSQLXML(String columnLabel, SQLXML xmlObject) throws SQLException {
        updateSQLXML(findColumn(columnLabel), xmlObject);

    }

    /**
     * Returns true if this either implements the interface argument or is directly or indirectly a wrapper
     * for an object that does. Returns false otherwise. If this implements the interface then return true,
     * else if this is a wrapper then return the result of recursively calling <code>isWrapperFor</code> on the wrapped
     * object. If this does not implement the interface and is not a wrapper, return false.
     * This method should be implemented as a low-cost operation compared to <code>unwrap</code> so that
     * callers can use this method to avoid expensive <code>unwrap</code> calls that may fail. If this method
     * returns true then calling <code>unwrap</code> with the same argument should succeed.
     * 
     * @param interfaces
     *            a Class defining an interface.
     * @return true if this implements the interface or directly or indirectly wraps an object that does.
     * @throws java.sql.SQLException
     *             if an error occurs while determining whether this is a wrapper
     *             for an object with the given interface.
     * @since 1.6
     */
    public boolean isWrapperFor(Class<?> iface) throws SQLException {
        checkClosed();

        // This works for classes that aren't actually wrapping anything
        return iface.isInstance(this);
    }

    /**
     * Returns an object that implements the given interface to allow access to non-standard methods,
     * or standard methods not exposed by the proxy.
     * The result may be either the object found to implement the interface or a proxy for that object.
     * If the receiver implements the interface then that is the object. If the receiver is a wrapper
     * and the wrapped object implements the interface then that is the object. Otherwise the object is
     * the result of calling <code>unwrap</code> recursively on the wrapped object. If the receiver is not a
     * wrapper and does not implement the interface, then an <code>SQLException</code> is thrown.
     * 
     * @param iface
     *            A Class defining an interface that the result must implement.
     * @return an object that implements the interface. May be a proxy for the actual implementing object.
     * @throws java.sql.SQLException
     *             If no object found that implements the interface
     * @since 1.6
     */
    public <T> T unwrap(java.lang.Class<T> iface) throws java.sql.SQLException {
        try {
            // This works for classes that aren't actually wrapping anything
            return iface.cast(this);
        } catch (ClassCastException cce) {
            throw SQLError.createSQLException("Unable to unwrap to " + iface.toString(), SQLError.SQL_STATE_ILLEGAL_ARGUMENT, getExceptionInterceptor());
        }
    }

    @SuppressWarnings("unchecked")
    public <T> T getObject(int columnIndex, Class<T> type) throws SQLException {
        if (type == null) {
            throw SQLError.createSQLException("Type parameter can not be null", SQLError.SQL_STATE_ILLEGAL_ARGUMENT, getExceptionInterceptor());
        }

        if (type.equals(Struct.class)) {
            throw new SQLFeatureNotSupportedException();
        } else if (type.equals(RowId.class)) {
            return (T) getRowId(columnIndex);
        } else if (type.equals(NClob.class)) {
            return (T) getNClob(columnIndex);
        } else if (type.equals(SQLXML.class)) {
            return (T) getSQLXML(columnIndex);
        }

        return super.getObject(columnIndex, type);
    }
}