/*
 * 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.
 */

/* $Id$ */

package org.apache.fop.render;

import java.io.File;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Map;
import java.util.MissingResourceException;

import javax.xml.transform.Source;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.sax.SAXResult;
import javax.xml.transform.stream.StreamSource;

import org.apache.commons.io.FileUtils;
import org.apache.commons.io.IOUtils;

import org.apache.fop.apps.FOUserAgent;
import org.apache.fop.apps.Fop;
import org.apache.fop.apps.FopFactory;
import org.apache.fop.apps.MimeConstants;

/**
 * Abstract base class for rendering (output) verification tests.
 */
public abstract class AbstractRenderingTest {

    private static final Map<String, String> MIME_MAP = new java.util.HashMap<String, String>();

    static {
        MIME_MAP.put(MimeConstants.MIME_PDF, ".pdf");
        MIME_MAP.put(MimeConstants.MIME_POSTSCRIPT, ".ps");
        MIME_MAP.put(MimeConstants.MIME_AFP, ".afp");
    }

    /** the JAXP TransformerFactory */
    protected TransformerFactory tFactory = TransformerFactory.newInstance();
    /** the FopFactory */
    protected final FopFactory fopFactory = FopFactory.newInstance(new File(".").toURI());

    /**
     * Renders a test file.
     * @param ua the user agent (with override set!)
     * @param resourceName the resource name for the FO file
     * @param suffix a suffix for the output filename
     * @param outputFormat MIME type of the requested output format
     * @return the output file
     * @throws Exception if an error occurs
     */
    protected File renderFile(FOUserAgent ua, String resourceName, String suffix,
            String outputFormat) throws Exception {
        String extension = MIME_MAP.get(outputFormat);
        assert extension != null;
        File outputFile = new File("build/test-results/" + resourceName + suffix + extension);
        File outputDir = outputFile.getParentFile();
        FileUtils.forceMkdir(outputDir);

        // Prepare input file
        InputStream in = getClass().getResourceAsStream(resourceName);
        if (in == null) {
            throw new MissingResourceException(resourceName + " not found in resources",
                    getClass().getName(), null);
        }
        try {
            Source src = new StreamSource(in);

            // Create output file
            OutputStream out = new java.io.FileOutputStream(outputFile);
            out = new java.io.BufferedOutputStream(out);
            try {
                Fop fop = fopFactory.newFop(outputFormat, ua, out);
                SAXResult res = new SAXResult(fop.getDefaultHandler());

                Transformer transformer = tFactory.newTransformer();
                transformer.transform(src, res);
            } finally {
                IOUtils.closeQuietly(out);
            }
        } finally {
            IOUtils.closeQuietly(in);
        }
        return outputFile;
    }

}
