package extended.forms;

import javax.jcr.Node;
import javax.jcr.RepositoryException;


import info.magnolia.jcr.util.MetaDataUtil;
import info.magnolia.jcr.util.NodeUtil;
import info.magnolia.module.form.templates.components.FormParagraph;
import info.magnolia.module.form.templates.components.SubStepFormModel;
import info.magnolia.module.form.templates.components.multistep.NavigationUtils;
import info.magnolia.module.form.templates.components.multistep.SubStepFormEngine;
import info.magnolia.objectfactory.Components;
import info.magnolia.registry.RegistrationException;
import info.magnolia.rendering.context.RenderingContext;
import info.magnolia.rendering.model.RenderingModel;
import info.magnolia.rendering.template.RenderableDefinition;
import info.magnolia.rendering.template.registry.TemplateDefinitionRegistry;
import info.magnolia.templating.functions.TemplatingFunctions;

/**
 * Custom sub step form model which allows sub steps to save the temporary data in the session when
 * the user clicks 'back'.
 */
public class ExtendedSubStepFormModel extends SubStepFormModel {

  /**
   * Constructor.
   * @param content the content
   * @param definition the definition
   * @param parent the parent
   * @param functions the templating function
   */
  public ExtendedSubStepFormModel(Node content,
      RenderableDefinition definition,
      RenderingModel<?> parent,
      TemplatingFunctions functions) {
    super(content, definition, parent, functions);
  }

  @Override
  protected SubStepFormEngine createFormEngine() throws RepositoryException {

    Node startPage = Components.getComponent(RenderingContext.class).getMainContent().getParent();
    Node startParagraphNode = NavigationUtils.findParagraphOfType(startPage, FormParagraph.class);

    if (startParagraphNode == null) {
      // Ideally we would return a view that describes the problem and how to resolve it
      throw new IllegalStateException("FormStepParagraph on page ["
          + NodeUtil.getPathIfPossible(content) + "] could not find a FormParagraph in its parent");
    }

    String templateId = MetaDataUtil.getTemplate(startParagraphNode);
    FormParagraph startParagraph = null;
    try {
      startParagraph = (FormParagraph) Components.getComponent(TemplateDefinitionRegistry.class)
          .getTemplateDefinition(templateId);
    } catch (RegistrationException e) {
      throw new RuntimeException(e.getMessage(), e);
    }

    ExtendedSubStepFormEngine subStepFormEngine = Components.newInstance(ExtendedSubStepFormEngine.class,
        startParagraphNode, startParagraph, startPage);
    subStepFormEngine.setStartPage(startPage);
    return subStepFormEngine;
  }

}