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 *  * This program and the accompanying materials are made available under the
 *  * terms of the Apache License, Version 2.0 which is available at
 *  * https://www.apache.org/licenses/LICENSE-2.0.
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 *  *  information regarding copyright ownership.
 *  * 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
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package org.deeplearning4j.nn.modelimport.keras.layers.core;

import lombok.extern.slf4j.Slf4j;
import org.deeplearning4j.nn.modelimport.keras.KerasLayer;
import org.deeplearning4j.nn.modelimport.keras.exceptions.InvalidKerasConfigurationException;
import org.deeplearning4j.nn.modelimport.keras.exceptions.UnsupportedKerasConfigurationException;
import org.deeplearning4j.nn.conf.RNNFormat;
import org.deeplearning4j.nn.conf.inputs.InputType;
import org.deeplearning4j.nn.conf.layers.misc.RepeatVector;
import org.deeplearning4j.nn.modelimport.keras.config.KerasLayerConfiguration;
import org.deeplearning4j.nn.modelimport.keras.utils.KerasLayerUtils;

import java.util.Map;

@Slf4j
public class KerasRepeatVector extends KerasLayer {

    /**
     * Constructor from parsed Keras layer configuration dictionary.
     *
     * @param layerConfig dictionary containing Keras layer configuration
     * @throws InvalidKerasConfigurationException     Invalid Keras config
     * @throws UnsupportedKerasConfigurationException Unsupported Keras config
     */
    public KerasRepeatVector(Map<String, Object> layerConfig)
            throws InvalidKerasConfigurationException, UnsupportedKerasConfigurationException {
        this(layerConfig, true);
    }

    /**
     * Constructor from parsed Keras layer configuration dictionary.
     *
     * @param layerConfig               dictionary containing Keras layer configuration
     * @param enforceTrainingConfig     whether to enforce training-related configuration options
     * @throws InvalidKerasConfigurationException Invalid Keras config
     * @throws UnsupportedKerasConfigurationException Unsupported Keras config
     */
    public KerasRepeatVector(Map<String, Object> layerConfig, boolean enforceTrainingConfig)
            throws InvalidKerasConfigurationException, UnsupportedKerasConfigurationException {
        super(layerConfig, enforceTrainingConfig);

        this.layer = new RepeatVector.Builder().repetitionFactor(getRepeatMultiplier(layerConfig, conf))
                .dataFormat(RNNFormat.NWC)
                .name(this.layerName).build();
    }

    /**
     * Get layer output type.
     *
     * @param  inputType    Array of InputTypes
     * @return              output type as InputType
     * @throws InvalidKerasConfigurationException Invalid Keras config
     */
    @Override
    public InputType getOutputType(InputType... inputType) throws InvalidKerasConfigurationException {
        if (inputType.length > 1)
            throw new InvalidKerasConfigurationException(
                    "Keras RepeatVector layer accepts only one input (received " + inputType.length + ")");
        return this.getRepeatVectorLayer().getOutputType(-1, inputType[0]);
    }

    /**
     * Get DL4J RepeatVector.
     *
     * @return  RepeatVector
     */
    public RepeatVector getRepeatVectorLayer() {
        return (RepeatVector) this.layer;
    }

    static int getRepeatMultiplier(Map<String, Object> layerConfig, KerasLayerConfiguration conf)
            throws InvalidKerasConfigurationException {
        Map<String, Object> innerConfig = KerasLayerUtils.getInnerLayerConfigFromConfig(layerConfig, conf);
        return  (int) innerConfig.get(conf.getLAYER_FIELD_REPEAT_MULTIPLIER());
    }


}
