package net.sourceforge.phpeclipse.wiki.actions.mediawiki;
//Parts of this sources are copied and modified from the jEdit Wikipedia plugin:
//http://www.djini.de/software/wikipedia/index.html
//
//The modified sources are available under the "Common Public License"
//with permission from the original author: Daniel Wunsch

import java.io.ByteArrayInputStream;

import net.sourceforge.phpeclipse.wiki.actions.mediawiki.connect.MediaWikiConnector;
import net.sourceforge.phpeclipse.wiki.editor.WikiEditor;
import net.sourceforge.phpeclipse.wiki.editor.WikiEditorPlugin;
import net.sourceforge.phpeclipse.wiki.preferences.Util;

import org.eclipse.core.resources.IContainer;
import org.eclipse.core.resources.IFile;
import org.eclipse.core.resources.IFolder;
import org.eclipse.core.resources.IResource;
import org.eclipse.core.resources.IResourceStatus;
import org.eclipse.core.resources.ResourcesPlugin;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IPath;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.core.runtime.Path;
import org.eclipse.core.runtime.SubProgressMonitor;
import org.eclipse.jface.action.IAction;
import org.eclipse.jface.text.BadLocationException;
import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.ITextSelection;
import org.eclipse.jface.text.TextSelection;
import org.eclipse.jface.viewers.ISelection;
import org.eclipse.ui.IEditorActionDelegate;
import org.eclipse.ui.IEditorPart;
import org.eclipse.ui.IFileEditorInput;
import org.eclipse.ui.IWorkbenchWindow;
import org.eclipse.ui.ide.IDE;
import org.eclipse.ui.internal.ide.IDEWorkbenchPlugin;
import org.eclipse.ui.texteditor.AbstractTextEditor;

public final class DownloadWikiLinkEditorAction implements IEditorActionDelegate {

  private IWorkbenchWindow window; 

  private AbstractTextEditor fEditor;

  public void dispose() {
  }

  public void init(IWorkbenchWindow window) {
    this.window = window;
  }

  public void selectionChanged(IAction action, ISelection selection) {
    if (selection.isEmpty()) {
      return;
    }
    if (selection instanceof TextSelection) {
      action.setEnabled(true);
      return;
    }
    if (window.getActivePage() != null && window.getActivePage().getActivePart() != null) {
      action.setEnabled(window.getActivePage().getActivePart().getClass().equals(WikiEditor.class));
    }
  }

  public void run(IAction action) {
    if (fEditor == null) {
      IEditorPart targetEditor = window.getActivePage().getActiveEditor();
      if (targetEditor != null && (targetEditor instanceof AbstractTextEditor)) {
        fEditor = (AbstractTextEditor) targetEditor;
      }
    }
    if (fEditor != null) {
      openWikiLinkOnSelection();
    }
  }

  public void setActiveEditor(IAction action, IEditorPart targetEditor) {
    if (targetEditor != null && (targetEditor instanceof AbstractTextEditor)) {
      fEditor = (AbstractTextEditor) targetEditor;
    }
  }

  public static String getWikiString(AbstractTextEditor editor, IDocument document, int initialPos) {
    try {
      int pos = initialPos;
      int line = document.getLineOfOffset(pos);
      int start = document.getLineOffset(line);
      int end = start + document.getLineInformation(line).getLength();

      /*
       * The line does not include \n or \r so pos can be > end. Making pos = end in this case is safe for the purposes of
       * determining the TextRegion at the cursor position
       */
      if (pos > end) {
        pos = end;
      }

      int offsetInLine = pos - start;
      String word = document.get(start, end - start);
      int wordlen = word.length();
      int wikiLinkStart = -1;
      int wikiLinkEnd = -1;

      for (int i = offsetInLine; i < wordlen; i++) {
        if (word.charAt(i) == ']' && i < wordlen - 1 && word.charAt(i + 1) == ']') {
          wikiLinkEnd = i;
          break;
        }
        if (word.charAt(i) == '|') {
          wikiLinkEnd = i;
          break;
        }
        if (word.charAt(i) == '#') {
          wikiLinkEnd = i;
          break;
        }
      }
      for (int i = offsetInLine; i >= 0; i--) {
        if (word.charAt(i) == '[' && i > 0 && word.charAt(i - 1) == '[') {
          wikiLinkStart = i + 1;
          break;
        }
        if (word.charAt(i) == '|') { // links wih different description
          wikiLinkEnd = i;
        }
        if (word.charAt(i) == '#') { // for links with anchors
          wikiLinkEnd = i;
        }
      }
      if (wikiLinkStart != (-1) && wikiLinkEnd != (-1) && wikiLinkStart < wikiLinkEnd) {
        return new String(word.toCharArray(), wikiLinkStart, wikiLinkEnd - wikiLinkStart);
      }
    } catch (BadLocationException e) {

    }
    return "";
  }

  public IDocument getDocument() {
    IDocument doc = fEditor.getDocumentProvider().getDocument(fEditor.getEditorInput());
    return doc;
  }

  public void openWikiLinkOnSelection() {
    IDocument doc = getDocument();
    ITextSelection selection = (ITextSelection) fEditor.getSelectionProvider().getSelection();
    int pos = selection.getOffset();
    String textRegion = getWikiString(fEditor, doc, pos);
    IFileEditorInput ei = (IFileEditorInput) fEditor.getEditorInput();
    openWikiFile(ei.getFile(), textRegion);
  }

  void openWikiFile(IFile cfile, String word) {
    if (word != null && !word.equals("")) {
      IFile file = getWikiFile(cfile, word);
      try {
        createNewFileIfNeeded(file, word);
        
        //				if (WikiEditorPlugin.getDefault().getPreferenceStore().getBoolean(WikiConstants.REUSE_EDITOR)) {
        //					saveIfNeeded();
        //					getActivePage().reuseEditor(reusableEditor, new FileEditorInput(file));
        //				} else {
        IEditorPart part = IDE.openEditor(WikiEditorPlugin.getDefault().getActivePage(), file, true);
        if (part != null && (part instanceof AbstractTextEditor)) {
          AbstractTextEditor newEditor = (AbstractTextEditor) part;
          word = Util.titleToDB(word);
          MediaWikiConnector mc = new MediaWikiConnector();
          String wikiText = mc.getWikiRawText(word, "http://en.wikibooks.org/w/wiki.phtml");
          if (wikiText!=null) {
            IDocument doc = newEditor.getDocumentProvider().getDocument(newEditor.getEditorInput());
            doc.set(wikiText);
          }
        }
        
        
        //					redrawText();
        //				}
      } catch (Exception e) {
        //			  WikiEditorPlugin.getDefault().logAndReport(WikiEditorPlugin.getResourceString(WikiConstants.RESOURCE_WIKI_ERROR_DIALOGUE_OPEN_WIKI_FILE_TITLE),
        // WikiPlugin.getResourceString(WikiConstants.RESOURCE_WIKI_ERROR_DIALOGUE_OPEN_WIKI_FILE_TEXT), e);
      }
    } 
  }

  private void createNewFileIfNeeded(IFile file, String word) throws CoreException {
    if (!file.exists()) {
      createWikiFile(file, word);
    }
  }

  private IFile getWikiFile(IFile file, String word) {
    String wikiFileName = Util.getWikiFileName(word, file, WikiEditorPlugin.HTML_OUTPUT_PATH);
    IPath path = new Path(wikiFileName);
    return ResourcesPlugin.getWorkspace().getRoot().getFileForLocation(path);
  }

  /**
   * Creates a folder resource handle for the folder with the given workspace path. This method does not create the folder resource;
   * this is the responsibility of <code>createFolder</code>.
   * 
   * @param folderPath
   *          the path of the folder resource to create a handle for
   * @return the new folder resource handle
   * @see #createFolder
   */
  private IFolder createFolderHandle(IPath folderPath) {
    return IDEWorkbenchPlugin.getPluginWorkspace().getRoot().getFolder(folderPath);
  }

  private void createFolder(IFolder folderHandle, IProgressMonitor monitor) throws CoreException {
    try {
      // Create the folder resource in the workspace
      // Recursive to create any folders which do not exist already
      if (!folderHandle.exists()) {
        IContainer parent = folderHandle.getParent();
        if (parent instanceof IFolder && (!((IFolder) parent).exists())) {
          createFolder((IFolder) parent, monitor);
        }
        //	            if (linkTargetPath != null)
        //        	            	folderHandle.createLink(linkTargetPath, IResource.ALLOW_MISSING_LOCAL, monitor);
        //	            else
        folderHandle.create(false, true, monitor);
      }
    } catch (CoreException e) {
      // If the folder already existed locally, just refresh to get contents
      if (e.getStatus().getCode() == IResourceStatus.PATH_OCCUPIED)
        folderHandle.refreshLocal(IResource.DEPTH_INFINITE, new SubProgressMonitor(monitor, 500));
      else
        throw e;
    }
  }

  private void createWikiFile(IFile file, String word) throws CoreException {
    IContainer parent = file.getParent();
    if (parent instanceof IFolder && (!((IFolder) parent).exists())) {
      createFolder((IFolder) parent, null);
    }
    String newText = "<!--" + word + "-->";
    byte[] buffer = newText.getBytes();
    ByteArrayInputStream source = new ByteArrayInputStream(buffer);
    file.create(source, true, null);
  }

}