/*
 * Copyright 2010 Red Hat, Inc. and/or its affiliates.
 *
 * Licensed 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.drools.core.io.impl;

import org.drools.core.io.internal.InternalResource;
import org.drools.core.util.IoUtils;
import org.kie.api.io.Resource;

import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;
import java.net.URL;
import java.util.Collection;

public class InputStreamResource extends BaseResource implements InternalResource {

    private transient InputStream stream;
    private String encoding;

    public InputStreamResource() { }

    public InputStreamResource(InputStream stream) {
        this(stream, null);
    }

    public InputStreamResource(InputStream stream,
                               String encoding) {
        if ( stream == null ) {
            throw new IllegalArgumentException( "stream cannot be null" );
        }
        this.stream = stream;
        this.encoding = encoding;
    }

    public InputStream getInputStream() throws IOException {
        return stream;
    }

    public String getEncoding() {
        return encoding;
    }

    public Reader getReader() throws IOException {
        if (this.encoding != null) {
            return new InputStreamReader( getInputStream(), this.encoding );
        } else {
            return new InputStreamReader( getInputStream(), IoUtils.UTF8_CHARSET );
        }
    }

    public URL getURL() throws IOException {
        throw new FileNotFoundException( "InputStream cannot be resolved to URL" );
    }
    
    public boolean hasURL() {
        return false;
    }
    
    public long getLastModified() {
        throw new IllegalStateException( "InputStream does have a modified date" );
    }
    
    public long getLastRead() {
        throw new IllegalStateException( "InputStream does have a modified date" );
    }
    
    public boolean isDirectory() {
        return false;
    }

    public Collection<Resource> listResources() {
        throw new RuntimeException( "This Resource cannot be listed, or is not a directory" );
    }

}