/*
 * Copyright (c) 2015, WSO2 Inc. (http://www.wso2.org) All Rights Reserved.
 *
 * WSO2 Inc. 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.wso2.carbon.ml.core.impl;

import org.wso2.carbon.context.PrivilegedCarbonContext;
import org.wso2.carbon.context.RegistryType;
import org.wso2.carbon.ml.core.exceptions.MLInputAdapterException;
import org.wso2.carbon.ml.core.interfaces.MLInputAdapter;
import org.wso2.carbon.registry.api.Registry;
import org.wso2.carbon.registry.api.RegistryException;
import org.wso2.carbon.registry.api.Resource;

import java.io.ByteArrayInputStream;
import java.io.InputStream;

/**
 * Implementation of {@link MLInputAdapter} for governance registry
 */
public class RegistryInputAdapter implements MLInputAdapter {

    @Override
    public InputStream read(String path) throws MLInputAdapterException {
        try {
            PrivilegedCarbonContext carbonContext = PrivilegedCarbonContext.getThreadLocalCarbonContext();
            Registry registry = carbonContext.getRegistry(RegistryType.SYSTEM_GOVERNANCE);
            Resource resource = registry.get(path);
            byte[] readArray = (byte[]) resource.getContent();
            ByteArrayInputStream bis = new ByteArrayInputStream(readArray);
            return bis;
        } catch (RegistryException e) {
            throw new MLInputAdapterException(String.format("Failed to read the model from uri %s: %s", path, e), e);
        }
    }
}
