/*******************************************************************************
 * Copyright (c) 2010 BSI Business Systems Integration AG.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     BSI Business Systems Integration AG - initial API and implementation
 ******************************************************************************/
package org.eclipse.scout.nls.sdk.ui;

import java.util.HashSet;
import java.util.regex.Pattern;

import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.Status;
import org.eclipse.scout.nls.sdk.internal.NlsCore;
import org.eclipse.scout.nls.sdk.internal.ui.formatter.IInputValidator;
import org.eclipse.scout.nls.sdk.model.INlsEntry;
import org.eclipse.scout.nls.sdk.model.workspace.project.INlsProject;
import org.eclipse.swt.SWT;

public final class InputValidator {
  private final static Pattern REGEX_NLS_KEY_NAME = Pattern.compile("\\b[A-Za-z0-9][a-zA-Z0-9_.\\-]{0,200}\\b");

  private InputValidator() {
  }

  public static IInputValidator getNlsKeyValidator(INlsProject project) {
    return getNlsKeyValidator(project, new String[0]);
  }

  public static IInputValidator getNlsKeyValidator(INlsProject project, String[] exceptions) {
    return new P_KeyEntryValidator(project, exceptions);
  }

  public static IInputValidator getDefaultTranslationValidator() {
    return new IInputValidator() {
      @Override
      public IStatus isValid(String value) {
        if (value.length() > 0) {
          return Status.OK_STATUS;
        }
        else {
          return new Status(IStatus.ERROR, NlsCore.PLUGIN_ID, SWT.OK, "The default translation must be set.", null);
        }
      }
    };
  }

  private final static class P_KeyEntryValidator implements IInputValidator {
    private final HashSet<String> m_exceptions;
    private final INlsProject m_project;

    public P_KeyEntryValidator(INlsProject project, String[] exceptions) {
      m_exceptions = new HashSet<String>(exceptions.length);
      for (String s : exceptions) {
        m_exceptions.add(s);
      }
      m_project = project;
    }

    private INlsEntry getEntry(String key) {
      return getEntry(m_project, key);
    }

    private INlsEntry getEntry(INlsProject project, String key) {
      if (project == null) {
        return null;
      }

      INlsEntry e = project.getEntry(key);
      if (e != null) {
        return e;
      }

      return getEntry(project.getParent(), key);
    }

    @Override
    public IStatus isValid(String value) {
      if (!m_exceptions.contains(value)) {
        INlsEntry e = getEntry(value);
        if (e != null) {
          if (e.getType() == INlsEntry.TYPE_LOCAL) {
            return new Status(IStatus.ERROR, NlsCore.PLUGIN_ID, SWT.OK, "A key '" + value + "' already exists!", null);
          }
          else {
            return new Status(IStatus.WARNING, NlsCore.PLUGIN_ID, SWT.OK, "The key '" + value + "' overrides an inherited entry.", null);
          }
        }
      }

      if (!REGEX_NLS_KEY_NAME.matcher(value).matches()) {
        return new Status(IStatus.ERROR, NlsCore.PLUGIN_ID, SWT.OK, "The key name is not valid.", null);
      }

      return Status.OK_STATUS;
    }
  } // end class P_KeyEntryValidator
}