package com.dmarcotte.handlebars.editor.actions;
import com.dmarcotte.handlebars.psi.HbPsiFile;
import com.dmarcotte.handlebars.psi.HbPsiUtil;
import com.intellij.codeInsight.editorActions.enter.EnterHandlerDelegateAdapter;
import com.intellij.openapi.actionSystem.DataContext;
import com.intellij.openapi.editor.Editor;
import com.intellij.openapi.editor.actionSystem.EditorActionHandler;
import com.intellij.openapi.editor.ex.EditorEx;
import com.intellij.openapi.editor.highlighter.EditorHighlighter;
import com.intellij.openapi.editor.highlighter.HighlighterIterator;
import com.intellij.openapi.util.Ref;
import com.intellij.psi.PsiElement;
import com.intellij.psi.PsiFile;
import org.jetbrains.annotations.NotNull;
/**
* Handler for custom plugin actions when {@code Enter} is typed by the user
*/
public class HbEnterHandler extends EnterHandlerDelegateAdapter {
public Result preprocessEnter(@NotNull final PsiFile file,
@NotNull final Editor editor,
@NotNull final Ref<Integer> caretOffset,
@NotNull final Ref<Integer> caretAdvance,
@NotNull final DataContext dataContext,
final EditorActionHandler originalHandler) {
/**
* if we are between open and close tags, we ensure the caret ends up in the "logical" place on Enter.
* i.e. "{{#foo}}<caret>{{/foo}}" becomes the following on Enter:
*
* {{#foo}}
* <caret>
* {{/foo}}
*
* (Note: <caret> may be indented depending on formatter settings.)
*/
if (file instanceof HbPsiFile
&& isBetweenHbTags(editor, file, caretOffset.get())) {
originalHandler.execute(editor, dataContext);
return Result.Default;
}
return Result.Continue;
}
/**
* Checks to see if {@code Enter} has been typed while the caret is between an open and close tag pair.
*
* @return true if between open and close tags, false otherwise
*/
private static boolean isBetweenHbTags(Editor editor, PsiFile file, int offset) {
if (offset == 0) return false;
CharSequence chars = editor.getDocument().getCharsSequence();
if (chars.charAt(offset - 1) != '}') return false;
EditorHighlighter highlighter = ((EditorEx)editor).getHighlighter();
HighlighterIterator iterator = highlighter.createIterator(offset - 1);
final PsiElement openerElement = file.findElementAt(iterator.getStart());
PsiElement openTag = HbPsiUtil.findParentOpenTagElement(openerElement);
if (openTag == null) {
return false;
}
iterator.advance();
if (iterator.atEnd()) {
// no more tokens, so certainly no close tag
return false;
}
final PsiElement closerElement = file.findElementAt(iterator.getStart());
PsiElement closeTag = HbPsiUtil.findParentCloseTagElement(closerElement);
// if we got this far, we're between open and close tags iff this is a close tag
return closeTag != null;
}
}