/*

 * Copyright (c) 1997, 2012, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package com.sun.codemodel.internal;

import java.io.IOException;

import java.io.OutputStream;

import java.io.OutputStreamWriter;

import java.io.Writer;

import java.nio.charset.CharsetEncoder;

import com.sun.codemodel.internal.util.EncoderFactory;

import com.sun.codemodel.internal.util.UnicodeEscapeWriter;

/**

 * Receives generated code and writes to the appropriate storage.

 *

 * @author

 *      Kohsuke Kawaguchi (kohsuke.kawaguchi@sun.com)

 */

public abstract class CodeWriter {

    /**

     * Encoding to be used by the writer. Null means platform specific encoding.

     *

     * @since 2.5

     */

    protected String encoding = null;

    /**

     * Called by CodeModel to store the specified file.

     * The callee must allocate a storage to store the specified file.

     *

     * <p>

     * The returned stream will be closed before the next file is

     * stored. So the callee can assume that only one OutputStream

     * is active at any given time.

     *

     * @param   pkg

     *      The package of the file to be written.

     * @param   fileName

     *      File name without the path. Something like

     *      "Foo.java" or "Bar.properties"

     */

    public abstract OutputStream openBinary( JPackage pkg, String fileName ) throws IOException;

    /**

     * Called by CodeModel to store the specified file.

     * The callee must allocate a storage to store the specified file.

     *

     * <p>

     * The returned stream will be closed before the next file is

     * stored. So the callee can assume that only one OutputStream

     * is active at any given time.

     *

     * @param   pkg

     *      The package of the file to be written.

     * @param   fileName

     *      File name without the path. Something like

     *      "Foo.java" or "Bar.properties"

     */

    public Writer openSource( JPackage pkg, String fileName ) throws IOException {

        final OutputStreamWriter bw = encoding != null

                ? new OutputStreamWriter(openBinary(pkg,fileName), encoding)

                : new OutputStreamWriter(openBinary(pkg,fileName));

        // create writer

        try {

            return new UnicodeEscapeWriter(bw) {

                // can't change this signature to Encoder because

                // we can't have Encoder in method signature

                private final CharsetEncoder encoder = EncoderFactory.createEncoder(bw.getEncoding());

                @Override

                protected boolean requireEscaping(int ch) {

                    // control characters

                    if( ch<0x20 && " \t\r\n".indexOf(ch)==-1 )  return true;

                    // check ASCII chars, for better performance

                    if( ch<0x80 )       return false;

                    return !encoder.canEncode((char)ch);

                }

            };

        } catch( Throwable t ) {

            return new UnicodeEscapeWriter(bw);

        }

    }

    /**

     * Called by CodeModel at the end of the process.

     */

    public abstract void close() throws IOException;

}