/**
 * ===========================================
 * LibLayout : a free Java layouting library
 * ===========================================
 *
 * Project Info:  http://reporting.pentaho.org/liblayout/
 *
 * (C) Copyright 2006-2007, by Pentaho Corporation and Contributors.
 *
 * This library is free software; you can redistribute it and/or modify it under the terms
 * of the GNU Lesser General Public License as published by the Free Software Foundation;
 * either version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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 Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License along with this
 * library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
 * Boston, MA 02111-1307, USA.
 *
 * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
 * in the United States and other countries.]
 *
 * ------------
 * $Id: StreamingRenderer.java 6489 2008-11-28 14:53:40Z tmorgner $
 * ------------
 * (C) Copyright 2006-2007, by Pentaho Corporation.
 */
package org.jfree.layouting.renderer;

import org.jfree.layouting.LayoutProcess;
import org.jfree.layouting.State;
import org.jfree.layouting.StateException;
import org.jfree.layouting.StatefullComponent;
import org.jfree.layouting.input.style.PseudoPage;
import org.jfree.layouting.layouter.context.LayoutStyle;
import org.jfree.layouting.layouter.context.PageContext;
import org.jfree.layouting.normalizer.content.NormalizationException;
import org.jfree.layouting.output.OutputProcessor;
import org.jfree.layouting.renderer.model.page.LogicalPageBox;
import org.jfree.layouting.renderer.process.CleanStreamedBoxesStep;
import org.jfree.layouting.renderer.process.ComputeBreakabilityStep;
import org.jfree.layouting.renderer.process.ComputeICMMetricsStep;
import org.jfree.layouting.renderer.process.ComputeMarginsStep;
import org.jfree.layouting.renderer.process.ComputeStaticPropertiesStep;
import org.jfree.layouting.renderer.process.ComputeTableICMMetricsStep;
import org.jfree.layouting.renderer.process.InfiniteMajorAxisLayoutStep;
import org.jfree.layouting.renderer.process.InfiniteMinorAxisLayoutStep;
import org.jfree.layouting.renderer.process.ParagraphLineBreakStep;
import org.jfree.layouting.renderer.process.SimplePaginationStep;
import org.jfree.layouting.renderer.process.TableRowHeightStep;
import org.jfree.layouting.renderer.process.TableValidationStep;
import org.jfree.layouting.renderer.process.ValidateModelStep;
import org.jfree.layouting.renderer.process.UpdateTokensStep;

/**
 * A renderer which builds a streaming page model.
 *
 * @author Thomas Morgner
 */
public class StreamingRenderer extends AbstractRenderer
{
  protected static class DefaultFlowRendererState extends RendererState
  {
    private ValidateModelStep validateModelStep;
    private TableValidationStep tableValidationStep;
    private ComputeStaticPropertiesStep staticPropertiesStep;
    private ComputeMarginsStep marginsStep;
    private ComputeICMMetricsStep icmMetricsStep;
    private ComputeTableICMMetricsStep tableICMMetricsStep;
    private ParagraphLineBreakStep paragraphLinebreakStep;
    private InfiniteMinorAxisLayoutStep minorAxisLayoutStep;
    private InfiniteMajorAxisLayoutStep majorAxisLayoutStep;
    private TableRowHeightStep tableRowHeightStep;
    private ComputeBreakabilityStep breakabilityStep;
    private SimplePaginationStep paginationStep;
    private CleanStreamedBoxesStep cleanBoxesStep;
    private UpdateTokensStep updateTokensStep;

    protected DefaultFlowRendererState(final StreamingRenderer renderer)
        throws StateException
    {
      super(renderer);
      this.validateModelStep = renderer.validateModelStep;
      this.tableValidationStep = renderer.tableValidationStep;
      this.staticPropertiesStep = renderer.staticPropertiesStep;

      this.marginsStep = renderer.marginsStep;
      this.icmMetricsStep = renderer.icmMetricsStep;
      this.tableICMMetricsStep = renderer.tableICMMetricsStep;
      this.paragraphLinebreakStep = renderer.paragraphLinebreakStep;
      this.minorAxisLayoutStep = renderer.minorAxisLayoutStep;
      this.majorAxisLayoutStep = renderer.majorAxisLayoutStep;
      this.tableRowHeightStep = renderer.tableRowHeightStep;
      this.breakabilityStep = renderer.breakabilityStep;
      this.paginationStep = renderer.paginationStep;
      this.cleanBoxesStep = renderer.cleanBoxesStep;
      this.updateTokensStep = renderer.updateTokensStep;
    }

    /**
     * Creates a restored instance of the saved component.
     * <p/>
     * By using this factory-like approach, we gain independence from having to
     * know the actual implementation. This makes things a lot easier.
     *
     * @param layoutProcess the layout process that controls it all
     * @return the saved state
     * @throws StateException
     */
    public StatefullComponent restore(final LayoutProcess layoutProcess)
        throws StateException
    {
      final StreamingRenderer defaultRenderer = new StreamingRenderer(layoutProcess, false);
      fill(defaultRenderer, layoutProcess);
      defaultRenderer.validateModelStep = this.validateModelStep;
      defaultRenderer.tableValidationStep = this.tableValidationStep;
      defaultRenderer.staticPropertiesStep = this.staticPropertiesStep;
      defaultRenderer.marginsStep = this.marginsStep;
      defaultRenderer.icmMetricsStep = this.icmMetricsStep;
      defaultRenderer.tableICMMetricsStep = this.tableICMMetricsStep;
      defaultRenderer.paragraphLinebreakStep = this.paragraphLinebreakStep;
      defaultRenderer.minorAxisLayoutStep = this.minorAxisLayoutStep;
      defaultRenderer.majorAxisLayoutStep = this.majorAxisLayoutStep;
      defaultRenderer.tableRowHeightStep = this.tableRowHeightStep;
      defaultRenderer.paginationStep = this.paginationStep;
      defaultRenderer.cleanBoxesStep = this.cleanBoxesStep;
      defaultRenderer.breakabilityStep = this.breakabilityStep;
      defaultRenderer.updateTokensStep = this.updateTokensStep;
      return defaultRenderer;
    }
  }

  private ValidateModelStep validateModelStep;
  private TableValidationStep tableValidationStep;
  private ComputeStaticPropertiesStep staticPropertiesStep;
  private ComputeMarginsStep marginsStep;
  private ComputeICMMetricsStep icmMetricsStep;
  private ComputeTableICMMetricsStep tableICMMetricsStep;
  private ParagraphLineBreakStep paragraphLinebreakStep;
  private InfiniteMinorAxisLayoutStep minorAxisLayoutStep;
  private InfiniteMajorAxisLayoutStep majorAxisLayoutStep;
  private TableRowHeightStep tableRowHeightStep;
  private ComputeBreakabilityStep breakabilityStep;
  private SimplePaginationStep paginationStep;
  private CleanStreamedBoxesStep cleanBoxesStep;
  private UpdateTokensStep updateTokensStep;

  protected StreamingRenderer(final LayoutProcess layoutProcess,
                              final boolean init)
  {
    super(layoutProcess, init);
    if (init)
    {
      this.validateModelStep = new ValidateModelStep();
      this.staticPropertiesStep = new ComputeStaticPropertiesStep();
      this.tableValidationStep = new TableValidationStep();
      this.marginsStep = new ComputeMarginsStep();
      this.paragraphLinebreakStep = new ParagraphLineBreakStep();
      this.icmMetricsStep = new ComputeICMMetricsStep();
      this.tableICMMetricsStep = new ComputeTableICMMetricsStep();
      this.minorAxisLayoutStep = new InfiniteMinorAxisLayoutStep();
      this.majorAxisLayoutStep = new InfiniteMajorAxisLayoutStep();
      this.tableRowHeightStep = new TableRowHeightStep();
      this.breakabilityStep = new ComputeBreakabilityStep();
      this.paginationStep = new SimplePaginationStep();
      this.cleanBoxesStep = new CleanStreamedBoxesStep();
      this.updateTokensStep = new UpdateTokensStep();
    }
  }

  public StreamingRenderer(final LayoutProcess layoutProcess)
  {
    this(layoutProcess, true);
  }

  /**
   * Todo: Using this renderer with an non-iterative output processor results
   * in trouble!
   *
   * @throws NormalizationException
   */
  protected void validateOutput() throws NormalizationException
  {
    final OutputProcessor outputProcessor = getLayoutProcess().getOutputProcessor();
    final LogicalPageBox logicalPageBox = getLogicalPageBox();

    if (outputProcessor.getMetaData().isIterative() == false)
    {
      if (logicalPageBox.isOpen())
      {
        return;
      }
    }

    if (validateModelStep.isLayoutable(logicalPageBox) == false)
    {
      return;
    }

    tableValidationStep.validate(logicalPageBox);

    updateTokensStep.compute
        (logicalPageBox, getLayoutProcess(), getPageContext());
    staticPropertiesStep.compute(logicalPageBox);
    marginsStep.compute(logicalPageBox);
    paragraphLinebreakStep.compute(logicalPageBox);

    icmMetricsStep.compute(logicalPageBox);
    tableICMMetricsStep.compute(logicalPageBox);

    minorAxisLayoutStep.compute(logicalPageBox);
    majorAxisLayoutStep.compute(logicalPageBox);
    tableRowHeightStep.compute(logicalPageBox);
    breakabilityStep.compute(logicalPageBox);

    paginationStep.performPagebreak(logicalPageBox);

    // A new page has been started. Recover the page-grid, then restart
    // everything from scratch. (We have to recompute, as the pages may
    // be different now, due to changed margins or page definitions)
    outputProcessor.processContent(logicalPageBox);

    // Now fire the pagebreak. This goes through all layers and informs all
    // components, that a pagebreak has been encountered and possibly a
    // new page has been set. It does not save the state or perform other
    // expensive operations. However, it updates the 'isPagebreakEncountered'
    // flag, which will be active until the input-feed received a new event.
    if (logicalPageBox.isOpen())
    {
      firePagebreak();
      cleanBoxesStep.compute(logicalPageBox);
    }
    else
    {
      outputProcessor.processingFinished();
    }
  }

  protected void firePagebreak() throws NormalizationException
  {
    // todo: Compute the current page and the pseudo-pages for this one.
    final PageContext pageContext = getRenderPageContext().getPageContext();
    final LayoutStyle style = pageContext.getStyle();

    // todo: Update the pseudo-pages (left | right, first)
    getLayoutProcess().pageBreakEncountered(null, new PseudoPage[0]);
  }


  public State saveState() throws StateException
  {
    return new DefaultFlowRendererState(this);
  }
}