/*
 * Copyright 2009 Google Inc.
 * 
 * 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 com.google.gwt.soyc.io;

import com.google.gwt.core.ext.linker.EmittedArtifact.Visibility;
import com.google.gwt.core.ext.linker.SyntheticArtifact;
import com.google.gwt.core.linker.SoycReportLinker;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.List;

/**
 * An {@link OutputDirectory} that writes its output as a list of GWT compiler
 * artifacts.
 */
public class ArtifactsOutputDirectory implements OutputDirectory {
  public static final String COMPILE_REPORT_DIRECTORY = "compile-report";

  /**
   * An in-memory output stream. When it is closed, its contents are saved to an
   * artifact.
   */
  private class OutputStreamForArtifact extends OutputStream {
    private ByteArrayOutputStream baos = new ByteArrayOutputStream();
    private boolean closed = false;
    private final String path;

    public OutputStreamForArtifact(String path) {
      this.path = path;
    }

    @Override
    public void close() {
      if (!closed) {
        closed = true;
        SyntheticArtifact newArtifact = new SyntheticArtifact(
            SoycReportLinker.class, COMPILE_REPORT_DIRECTORY + "/" + path,
            baos.toByteArray());
        newArtifact.setVisibility(Visibility.Private);
        artifacts.add(newArtifact);
        baos = null;
      }
    }

    @Override
    public void write(byte b[]) throws IOException {
      baos.write(b);
    }

    @Override
    public void write(byte b[], int off, int len) throws IOException {
      baos.write(b, off, len);
    }

    @Override
    public void write(int b) throws IOException {
      baos.write(b);
    }
  }

  private List<SyntheticArtifact> artifacts = new ArrayList<SyntheticArtifact>();

  /**
   * Return the list of artifacts that have been written so far.
   */
  public List<SyntheticArtifact> getArtifacts() {
    return artifacts;
  }

  public OutputStream getOutputStream(String path) throws IOException {
    return new OutputStreamForArtifact(path);
  }

}