/*
 * Copyright (c) 2014, the Dart project authors.
 * 
 * Licensed under the Eclipse Public License v1.0 (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.eclipse.org/legal/epl-v10.html
 * 
 * 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.dart.engine.internal.task;

import com.google.dart.engine.context.AnalysisException;
import com.google.dart.engine.element.HtmlElement;
import com.google.dart.engine.error.AnalysisError;
import com.google.dart.engine.html.ast.HtmlUnit;
import com.google.dart.engine.internal.context.InternalAnalysisContext;
import com.google.dart.engine.internal.context.RecordingErrorListener;
import com.google.dart.engine.internal.element.angular.AngularApplication;
import com.google.dart.engine.internal.html.angular.AngularHtmlUnitResolver;
import com.google.dart.engine.source.Source;
import com.google.dart.engine.utilities.source.LineInfo;

/**
 * Instances of the class {@code ResolveAngularEntryHtmlTask} resolve a specific HTML file as an
 * Angular entry point.
 */
public class ResolveAngularEntryHtmlTask extends AnalysisTask {
  /**
   * The source to be resolved.
   */
  private final Source source;

  /**
   * The time at which the contents of the source were last modified.
   */
  private long modificationTime;

  /**
   * The HTML unit to be resolved.
   */
  private HtmlUnit unit;

  /**
   * The listener to record errors.
   */
  private final RecordingErrorListener errorListener = new RecordingErrorListener();

  /**
   * The {@link HtmlUnit} that was resolved by this task.
   */
  private HtmlUnit resolvedUnit;

  /**
   * The element produced by resolving the source.
   */
  private HtmlElement element = null;

  /**
   * The Angular application to resolve in context of.
   */
  private AngularApplication application;

  /**
   * Initialize a newly created task to perform analysis within the given context.
   * 
   * @param context the context in which the task is to be performed
   * @param source the source to be resolved
   * @param modificationTime the time at which the contents of the source were last modified
   * @param unit the HTML unit to be resolved
   */
  public ResolveAngularEntryHtmlTask(InternalAnalysisContext context, Source source,
      long modificationTime, HtmlUnit unit) {
    super(context);
    this.source = source;
    this.modificationTime = modificationTime;
    this.unit = unit;
  }

  @Override
  public <E> E accept(AnalysisTaskVisitor<E> visitor) throws AnalysisException {
    return visitor.visitResolveAngularEntryHtmlTask(this);
  }

  /**
   * Returns the {@link AngularApplication} for the Web application with this Angular entry point,
   * maybe {@code null} if not an Angular entry point.
   */
  public AngularApplication getApplication() {
    return application;
  }

  public HtmlElement getElement() {
    return element;
  }

  /**
   * The resolution errors that were discovered while resolving the source.
   */
  public AnalysisError[] getEntryErrors() {
    return errorListener.getErrorsForSource(source);
  }

  /**
   * Returns {@link AnalysisError}s recorded for the given {@link Source}.
   */
  public AnalysisError[] getErrors(Source source) {
    return errorListener.getErrorsForSource(source);
  }

  /**
   * Return the time at which the contents of the source that was parsed were last modified, or a
   * negative value if the task has not yet been performed or if an exception occurred.
   * 
   * @return the time at which the contents of the source that was parsed were last modified
   */
  public long getModificationTime() {
    return modificationTime;
  }

  /**
   * Return the {@link HtmlUnit} that was resolved by this task.
   * 
   * @return the {@link HtmlUnit} that was resolved by this task
   */
  public HtmlUnit getResolvedUnit() {
    return resolvedUnit;
  }

  /**
   * Return the source that was or is to be resolved.
   * 
   * @return the source was or is to be resolved
   */
  public Source getSource() {
    return source;
  }

  @Override
  protected String getTaskDescription() {
    if (source == null) {
      return "resolve as Angular entry point null source";
    }
    return "resolve as Angular entry point " + source.getFullName();
  }

  @Override
  protected void internalPerform() throws AnalysisException {
    //
    // Prepare for resolution.
    //
    LineInfo lineInfo = getContext().getLineInfo(source);
    //
    // Try to resolve as an Angular entry point.
    //
    application = new AngularHtmlUnitResolver(getContext(), errorListener, source, lineInfo, unit).calculateAngularApplication();
    //
    // Perform resolution.
    //
    if (application != null) {
      new AngularHtmlUnitResolver(getContext(), errorListener, source, lineInfo, unit).resolveEntryPoint(application);
    }
    //
    // Remember the resolved unit.
    //
    resolvedUnit = unit;
  }
}