/*
    * Copyright (C) 2003-2010 eXo Platform SAS.
    *
    * This program is free software; you can redistribute it and/or
    * modify it under the terms of the GNU Affero General Public License
    * as published by the Free Software Foundation; either version 3
    * of the License, or (at your option) any later version.
    *
    * This program 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 General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program; if not, see<http://www.gnu.org/licenses/>.
   */
  package org.exoplatform.wiki.service.wysiwyg;
  
  import org.apache.commons.lang.StringUtils;
  import org.exoplatform.commons.utils.PageList;
  import org.exoplatform.container.ExoContainerContext;
  import org.exoplatform.container.PortalContainer;
  import org.exoplatform.services.log.ExoLogger;
  import org.exoplatform.services.log.Log;
  import org.exoplatform.wiki.WikiException;
  import org.exoplatform.wiki.mow.api.Page;
  import org.exoplatform.wiki.mow.api.Wiki;
  import org.exoplatform.wiki.mow.api.WikiType;
  import org.exoplatform.wiki.resolver.TitleResolver;
  import org.exoplatform.wiki.service.*;
  import org.exoplatform.wiki.service.search.SearchResult;
  import org.exoplatform.wiki.service.search.WikiSearchData;
  import org.exoplatform.wiki.utils.Utils;
  import org.xwiki.component.annotation.Component;
  import org.xwiki.context.Execution;
  import org.xwiki.gwt.wysiwyg.client.wiki.*;
  import org.xwiki.gwt.wysiwyg.client.wiki.WikiService;
  import org.xwiki.model.reference.DocumentReference;
  
  import javax.inject.Inject;
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.List;
  
  @Component
  public class DefaultWikiService implements WikiService {
    /**
     * Default Wiki logger to report errors correctly.
     */
    private static Log                     log                      = ExoLogger.getLogger("wiki:GWTWikiService");
  
    /** Execution context handler, needed for accessing the WikiContext. */
    @Inject
    private Execution                      execution;
  
    /**
     * The service used to create links.
     */
    @Inject
    private LinkService                    linkService;
  
    /**
     * The object used to convert between client and server entity reference.
     */
    private final EntityReferenceConverter entityReferenceConverter = new EntityReferenceConverter();
  
    private WikiContext getWikiContext() {
      return (WikiContext) execution.getContext().getProperty(WikiContext.WIKICONTEXT);
    }
  
    /**
     * {@inheritDoc}
     *
     * @see WikiService#isMultiWiki()
     */
    @Override
    public Boolean isMultiWiki() {
      return false;
    }
  
    /**
     * {@inheritDoc}
     *
     * @see WikiService#getVirtualWikiNames()
     */
    @Override
    public List<String> getVirtualWikiNames() {
      List<String> virtualWikiNamesList = new ArrayList<String>();
      return virtualWikiNamesList;
    }
  
    /**
     * {@inheritDoc}
     *
     * @see WikiService#getSpaceNames(String)
     */
    @Override
    public List<String> getSpaceNames(String wikiType) {
      List<String> spaceNames = new ArrayList<>();
     org.exoplatform.wiki.service.WikiService wikiService = ExoContainerContext.getCurrentContainer()
             .getComponentInstanceOfType(org.exoplatform.wiki.service.WikiService.class);
     try {
       Collection<Wiki> wikis = wikiService.getWikisByType(wikiType);
       for (Wiki wiki : wikis) {
         spaceNames.add(wiki.getOwner());
       }
     } catch(WikiException e) {
       log.error("Cannot get space names - Cause : " + e.getMessage(), e);
     }
     return spaceNames;
   }
 
   /**
    * {@inheritDoc}
    *
    * @see WikiService#getPageNames(String, String)
    */
   @Override
   public List<String> getPageNames(String wikiName, String spaceName) {
     org.exoplatform.wiki.service.WikiService wservice = (org.exoplatform.wiki.service.WikiService) PortalContainer.getComponent(org.exoplatform.wiki.service.WikiService.class);
     try {
       WikiContext wikiContext = getWikiContext();
       WikiSearchData data = new WikiSearchData("", null, wikiContext.getType(), wikiContext.getOwner());
       PageList<SearchResult> results = wservice.search(data);
       List<String> pagesNames = new ArrayList<String>();
       if(results != null) {
         List<DocumentReference> documentReferences = prepareDocumentReferenceList(results);
         List<WikiPage> wikiPages = getWikiPages(documentReferences);
         for (WikiPage page : wikiPages) {
           String pageName = page.getTitle();
           if (!pagesNames.contains(pageName)) {
             pagesNames.add(pageName);
           }
         }
       }
       return pagesNames;
     } catch (Exception e) {
       log.error("Exception happened when list pages name", e);
       throw new RuntimeException("Failed to list Wiki pages name.", e);
     }
   }
 
   /**
    * {@inheritDoc}
    *
    * @see WikiService#getRecentlyModifiedPages(String, int, int)
    */
   public List<WikiPage> getRecentlyModifiedPages(String wikiName, int start, int count) {
     WikiContext wikiContext = getWikiContext();
     org.exoplatform.wiki.service.WikiService wservice =
         (org.exoplatform.wiki.service.WikiService) PortalContainer.getComponent(org.exoplatform.wiki.service.WikiService.class);
 
     // Create search condition by current user and recently
     WikiSearchData data = new WikiSearchData(StringUtils.EMPTY, "*", wikiContext.getType(), wikiContext.getOwner());
     // TODO add a property in the search data to get only recent pages
     //data.addPropertyConstraint(String.format(" AND (  ( exo:lastModifier='%s' ) )",
     //                           ConversationState.getCurrent().getIdentity().getUserId()));
     data.setSort("exo:lastModifiedDate");
     data.setOrder("DESC");
     data.setLimit(count);
 
     // Call wiki service to execute search
     try {
       PageList<SearchResult> results = wservice.search(data);
       List<DocumentReference> documentReferences = prepareDocumentReferenceList(results);
       return getWikiPages(documentReferences);
     } catch (Exception e) {
       log.error("Exception happened when searching pages", e);
       throw new RuntimeException("Failed to search Wiki pages.", e);
     }
   }
 
   /**
    * {@inheritDoc}
    *
    * @see WikiService#getMatchingPages(String, String, int, int)
    */
   public List<WikiPage> getMatchingPages(String wikiName, String keyword, int start, int count) {
     String quote = "'";
     String doubleQuote = "''";
     String escapedKeyword = keyword.replaceAll(quote, doubleQuote).toLowerCase();
     org.exoplatform.wiki.service.WikiService wservice = (org.exoplatform.wiki.service.WikiService) PortalContainer.getComponent(org.exoplatform.wiki.service.WikiService.class);
 
     try {
       WikiContext wikiContext = getWikiContext();
       WikiSearchData data = new WikiSearchData(escapedKeyword, escapedKeyword, wikiContext.getType(), wikiContext.getOwner());
       PageList<SearchResult> results = wservice.search(data);
       List<DocumentReference> documentReferences = prepareDocumentReferenceList(results);
       return getWikiPages(documentReferences);
     } catch (Exception e) {
       log.error("Exception happened when searching pages", e);
       throw new RuntimeException("Failed to search Wiki pages.", e);
     }
   }
 
   /**
    * Helper function to create a list of {@link WikiPage}s from a list of
    * document references.
    *
    * @param documentReferences a list of document references
    * @return the list of {@link WikiPage}s corresponding to the given document
    *         references
    * @throws Exception if anything goes wrong while creating the list of
    *           {@link WikiPage}s
    */
   private List<WikiPage> getWikiPages(List<DocumentReference> documentReferences) throws Exception {
     org.exoplatform.wiki.service.WikiService wservice = (org.exoplatform.wiki.service.WikiService) PortalContainer.getComponent(org.exoplatform.wiki.service.WikiService.class);
     List<WikiPage> wikiPages = new ArrayList<>();
     for (DocumentReference documentReference : documentReferences) {
       WikiPage wikiPage = new WikiPage();
       wikiPage.setReference(entityReferenceConverter.convert(documentReference).getEntityReference());
       String pageId = documentReference.getName();
       String wikiOwner = documentReference.getParent().getName();
       String wikiType = documentReference.getParent().getParent().getName();
       Page page = wservice.getPageByRootPermission(wikiType, wikiOwner, pageId);
       wikiPage.setTitle(page.getTitle());
       wikiPage.setUrl(pageId);
       wikiPages.add(wikiPage);
     }
     return wikiPages;
   }
 
   /**
    * {@inheritDoc}
    *
    * @see WikiService#getEntityConfig(org.xwiki.gwt.wysiwyg.client.wiki.EntityReference,
    *      ResourceReference)
    */
   public EntityConfig getEntityConfig(org.xwiki.gwt.wysiwyg.client.wiki.EntityReference origin, ResourceReference destination) {
     return linkService.getEntityConfig(origin, destination);
   }
 
   /**
    * {@inheritDoc}
    *
    * @see WikiService#getAttachment(AttachmentReference)
    */
   @Override
   public Attachment getAttachment(AttachmentReference attachmentReference) {
     // Clean attachment filename to be synchronized with all attachment operations.
     String cleanedFileName = attachmentReference.getFileName();
     cleanedFileName = Utils.escapeIllegalCharacterInName(cleanedFileName);
     attachmentReference.setFileName(cleanedFileName);
     WikiPageReference pageReference = attachmentReference.getWikiPageReference();
     org.exoplatform.wiki.service.WikiService wservice = (org.exoplatform.wiki.service.WikiService) PortalContainer.getComponent(org.exoplatform.wiki.service.WikiService.class);
     Page page;
     try {
       cleanedFileName = TitleResolver.getId(cleanedFileName, false);
       page = wservice.getExsitedOrNewDraftPageById(pageReference.getWikiName(), pageReference.getSpaceName(), pageReference.getPageName());
       if (page == null) {
         return null;
       }
 
       org.exoplatform.wiki.mow.api.Attachment attachment = wservice.getAttachmentOfPageByName(cleanedFileName, page);
       if (attachment == null) {
         log.warn(String.format("Failed to get attachment: %s not found.", cleanedFileName));
         return null;
       }
 
       Attachment attach = new Attachment();
       attach.setReference(attachmentReference.getEntityReference());
       attach.setUrl(attachment.getDownloadURL());
       return attach;
     } catch (Exception e) {
       log.error("Failed to get attachment: there was a problem with getting the document on the server.", e);
       return null;
     }
   }
 
   /**
    * {@inheritDoc}
    *
    * @see WikiService#getImageAttachments(WikiPageReference)
    */
   public List<Attachment> getImageAttachments(WikiPageReference reference) {
     List<Attachment> imageAttachments = new ArrayList<Attachment>();
     List<Attachment> allAttachments = getAttachments(reference);
     for (Attachment attachment : allAttachments) {
       if (attachment.getMimeType().startsWith("image/")) {
         imageAttachments.add(attachment);
       }
     }
     return imageAttachments;
   }
 
   /**
    * {@inheritDoc}
    *
    * @see WikiService#getAttachments(WikiPageReference)
    */
   @Override
   public List<Attachment> getAttachments(WikiPageReference documentReference) {
     try {
       String wikiName = documentReference.getWikiName();
       String spaceName = documentReference.getSpaceName();
       String pageName = documentReference.getPageName();
       if (log.isTraceEnabled()) {
         log.trace("Getting attachments of page : " + wikiName + "." + spaceName + "." + pageName);
       }
       List<Attachment> attachments = new ArrayList<Attachment>();
       org.exoplatform.wiki.service.WikiService wservice = (org.exoplatform.wiki.service.WikiService) PortalContainer.getComponent(org.exoplatform.wiki.service.WikiService.class);
       Page page = wservice.getExsitedOrNewDraftPageById(wikiName, spaceName, TitleResolver.getId(pageName, false));
       List<org.exoplatform.wiki.mow.api.Attachment> attachs = wservice.getAttachmentsOfPage(page);
       for (org.exoplatform.wiki.mow.api.Attachment attach : attachs) {
         AttachmentReference attachmentReference = new AttachmentReference(attach.getName(), documentReference);
         EntityReference entityReference = attachmentReference.getEntityReference();
         entityReference.setType(org.xwiki.gwt.wysiwyg.client.wiki.EntityReference.EntityType.ATTACHMENT);
         Attachment currentAttach = new Attachment();
         currentAttach.setUrl(attach.getDownloadURL());
         currentAttach.setReference(entityReference);
         currentAttach.setMimeType(attach.getMimeType());
         attachments.add(currentAttach);
       }
       return attachments;
     } catch (Exception e) {
       throw new RuntimeException("Failed to retrieve the list of attachments.", e);
     }
   }
 
   /**
    * {@inheritDoc}
    *
    * @see WikiService#getUploadURL(org.xwiki.gwt.wysiwyg.client.wiki.WikiPageReference)
    */
   @Override
   public String getUploadURL(WikiPageReference documentReference) {
     StringBuilder sb = new StringBuilder();
     sb.append("/").append(PortalContainer.getCurrentPortalContainerName()).append("/");
     sb.append(PortalContainer.getCurrentRestContextName()).append("/wiki/upload/");
     sb.append(documentReference.getWikiName()).append("/").append(documentReference.getSpaceName());
     sb.append("/").append(documentReference.getPageName()).append("/");
     return sb.toString();
   }
 
   /**
    * {@inheritDoc}
    *
    * @see WikiService#parseLinkReference(String,
    *      org.xwiki.gwt.wysiwyg.client.wiki.EntityReference)
    */
   public ResourceReference parseLinkReference(String linkReference, org.xwiki.gwt.wysiwyg.client.wiki.EntityReference baseReference) {
     return linkService.parseLinkReference(linkReference, baseReference);
   }
 
   /**
    * Helper function to prepare a list of {@link WikiPage} (with full name,
    * title, etc) from a list of search results.
    *
    * @param results the list of the search results
    * @return the list of {@link WikiPage}s corresponding to the passed names
    * @throws Exception if anything goes wrong retrieving the documents
    */
   private List<DocumentReference> prepareDocumentReferenceList(PageList<SearchResult> results) throws Exception {
     List<DocumentReference> documentReferences = new ArrayList<DocumentReference>();
     for (SearchResult result : results.getAll()) {
       String nodeName = result.getPageName();
       if (nodeName != null && nodeName.length() > 0 && nodeName.startsWith("/")) {
         nodeName = nodeName.substring(1);
       }
       WikiContext wikiContext = getWikiContext();
       log.info("Prepair DocumentReference : " + wikiContext.getType() + "@" + wikiContext.getOwner() + "@" + nodeName);
       documentReferences.add(new DocumentReference(wikiContext.getType(), wikiContext.getOwner(), nodeName));
     }
     return documentReferences;
   }
 }