/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.qpid.protonj2.codec.encoders.primitives;

import org.apache.qpid.protonj2.buffer.ProtonBuffer;
import org.apache.qpid.protonj2.codec.EncoderState;
import org.apache.qpid.protonj2.codec.EncodingCodes;
import org.apache.qpid.protonj2.codec.encoders.AbstractPrimitiveTypeEncoder;

/**
 * Encoder of AMQP Float type values to a byte stream.
 */
public final class FloatTypeEncoder extends AbstractPrimitiveTypeEncoder<Float> {

    @Override
    public Class<Float> getTypeClass() {
        return Float.class;
    }

    @Override
    public void writeType(ProtonBuffer buffer, EncoderState state, Float value) {
        buffer.writeByte(EncodingCodes.FLOAT);
        buffer.writeFloat(value.floatValue());
    }

    /**
     * Write the full AMQP type data for the float to the given byte buffer.
     *
     * This can consist of writing both a type constructor value and the bytes that make up the
     * value of the type being written.
     *
     * @param buffer
     * 		The {@link ProtonBuffer} instance to write the encoding to.
     * @param state
     * 		The {@link EncoderState} for use in encoding operations.
     * @param value
     * 		The float value to encode.
     */
    public void writeType(ProtonBuffer buffer, EncoderState state, float value) {
        buffer.writeByte(EncodingCodes.FLOAT);
        buffer.writeFloat(value);
    }

    @Override
    public void writeRawArray(ProtonBuffer buffer, EncoderState state, Object[] values) {
        buffer.writeByte(EncodingCodes.FLOAT);
        for (Object value : values) {
            buffer.writeFloat(((Float) value).floatValue());
        }
    }

    public void writeRawArray(ProtonBuffer buffer, EncoderState state, float[] values) {
        buffer.writeByte(EncodingCodes.FLOAT);
        for (float value : values) {
            buffer.writeFloat(value);
        }
    }

    public void writeArray(ProtonBuffer buffer, EncoderState state, float[] values) {
        if (values.length < 63) {
            writeAsArray8(buffer, state, values);
        } else {
            writeAsArray32(buffer, state, values);
        }
    }

    private void writeAsArray8(ProtonBuffer buffer, EncoderState state, float[] values) {
        buffer.writeByte(EncodingCodes.ARRAY8);

        int startIndex = buffer.getWriteOffset();

        buffer.writeByte((byte) 0);
        buffer.writeByte((byte) values.length);

        // Write the array elements after writing the array length
        writeRawArray(buffer, state, values);

        // Move back and write the size
        int endIndex = buffer.getWriteOffset();
        long writeSize = endIndex - startIndex - Byte.BYTES;

        buffer.setByte(startIndex, (byte) writeSize);
    }

    private void writeAsArray32(ProtonBuffer buffer, EncoderState state, float[] values) {
        buffer.writeByte(EncodingCodes.ARRAY32);

        int startIndex = buffer.getWriteOffset();

        buffer.writeInt(0);
        buffer.writeInt(values.length);

        // Write the array elements after writing the array length
        writeRawArray(buffer, state, values);

        // Move back and write the size
        int endIndex = buffer.getWriteOffset();
        long writeSize = endIndex - startIndex - Integer.BYTES;

        if (writeSize > Integer.MAX_VALUE) {
            throw new IllegalArgumentException("Cannot encode given array, encoded size to large: " + writeSize);
        }

        buffer.setInt(startIndex, (int) writeSize);
    }
}
