/*
* Copyright 2011-2014 Gregory Shrago
*
* Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
*
* 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 org.intellij.jflex.editor;
import com.intellij.codeInsight.TailType;
import com.intellij.codeInsight.completion.*;
import com.intellij.codeInsight.lookup.LookupElement;
import com.intellij.codeInsight.lookup.LookupElementBuilder;
import com.intellij.codeInsight.lookup.TailTypeDecorator;
import com.intellij.lang.Language;
import com.intellij.openapi.editor.Document;
import com.intellij.openapi.util.text.StringUtil;
import com.intellij.patterns.StandardPatterns;
import com.intellij.psi.PsiElement;
import com.intellij.psi.PsiFile;
import com.intellij.psi.PsiFileFactory;
import com.intellij.psi.codeStyle.CodeStyleSettingsManager;
import com.intellij.psi.impl.source.tree.LeafPsiElement;
import com.intellij.psi.impl.source.tree.TreeUtil;
import com.intellij.psi.tree.IElementType;
import com.intellij.psi.util.PsiTreeUtil;
import com.intellij.util.ProcessingContext;
import org.intellij.grammar.parser.GeneratedParserUtilBase;
import org.intellij.jflex.parser.JFlexFileType;
import org.intellij.jflex.psi.JFlexDeclarationsSection;
import org.intellij.jflex.psi.JFlexExpression;
import org.intellij.jflex.psi.JFlexUserCodeSection;
import org.intellij.jflex.psi.impl.JFlexFileImpl;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;
import java.util.Collection;
import java.util.Collections;
import static com.intellij.patterns.PlatformPatterns.psiElement;
import static org.intellij.jflex.psi.JFlexTypes.*;
/**
* @author gregsh
*/
public class JFlexCompletionContributor extends CompletionContributor {
public JFlexCompletionContributor() {
extend(CompletionType.BASIC, psiElement().inFile(StandardPatterns.instanceOf(JFlexFileImpl.class)), new CompletionProvider<CompletionParameters>() {
@Override
protected void addCompletions(@NotNull CompletionParameters parameters,
ProcessingContext context,
@NotNull CompletionResultSet result) {
for (String keyword : suggestKeywords(parameters.getPosition())) {
result.addElement(createKeywordLookupItem(keyword));
}
}
});
}
@Override
public void beforeCompletion(@NotNull CompletionInitializationContext context) {
context.setDummyIdentifier(CompletionUtil.DUMMY_IDENTIFIER_TRIMMED);
}
private static Collection<String> suggestKeywords(PsiElement position) {
if (position instanceof LeafPsiElement && ((LeafPsiElement)position).getElementType() == FLEX_STRING) return Collections.emptySet();
if (PsiTreeUtil.getParentOfType(position, JFlexUserCodeSection.class) != null) return Collections.emptySet();
boolean inDeclare = PsiTreeUtil.getParentOfType(position, JFlexDeclarationsSection.class) != null;
PsiFile flexFile = position.getContainingFile();
Language language = flexFile.getLanguage();
String flexFileText = flexFile.getText();
int positionOffset = position.getTextRange().getEndOffset();
JFlexExpression expr = PsiTreeUtil.getParentOfType(position, JFlexExpression.class);
final boolean inMacro =
expr != null && expr.getText().substring(0, positionOffset - expr.getTextRange().getStartOffset()).indexOf('\n') == -1;
String fragment = (inDeclare ? "%%\n" : "%%\n%%\n") + flexFileText.substring(flexFileText.lastIndexOf("%%", positionOffset-1) + 2, positionOffset);
boolean empty = StringUtil.isEmptyOrSpaces(fragment);
final String text = empty ? CompletionInitializationContext.DUMMY_IDENTIFIER : fragment;
int completionOffset = empty ? 0 : fragment.length();
PsiFile file = PsiFileFactory.getInstance(flexFile.getProject()).createFileFromText("a.flex", language, text, true, false);
GeneratedParserUtilBase.CompletionState state = new GeneratedParserUtilBase.CompletionState(completionOffset) {
@Nullable
@Override
public String convertItem(Object o) {
if (o == null) return null;
if (o instanceof IElementType[]) return super.convertItem(o);
if (o == FLEX_ID || o == FLEX_CHAR || o == FLEX_ESCAPED_CHAR || o == FLEX_STRING || o == FLEX_NUMBER || o == FLEX_JAVA) return null;
String text = o.toString();
return text.length() == 1 || inMacro && text.startsWith("%") || !inMacro && text.startsWith("[")? null : text;
}
};
file.putUserData(GeneratedParserUtilBase.COMPLETION_STATE_KEY, state);
TreeUtil.ensureParsed(file.getNode());
return state.items;
}
private static LookupElement createKeywordLookupItem(String keyword) {
LookupElementBuilder builder = LookupElementBuilder.create(keyword.toLowerCase()).withCaseSensitivity(false).bold();
boolean braces = keyword.endsWith("{") || keyword.endsWith("}");
if (!braces) {
return keyword.startsWith("%") ? TailTypeDecorator.withTail(builder, TailType.SPACE) : builder;
}
else {
final String closing = keyword.endsWith("{") ? keyword.substring(0, keyword.length()-1) + "}" : null;
return PrioritizedLookupElement.withPriority(builder.withInsertHandler(new InsertHandler<LookupElement>() {
@Override
public void handleInsert(InsertionContext context, LookupElement item) {
int caret = context.getTailOffset();
Document document = context.getDocument();
StringBuilder sb = new StringBuilder("\n");
caret += sb.length();
if (closing != null) {
int indentSize = CodeStyleSettingsManager.getInstance(context.getProject()).
getCurrentSettings().getIndentSize(JFlexFileType.INSTANCE);
sb.append(StringUtil.repeat(" ", indentSize));
caret += indentSize;
sb.append("\n").append(closing).append("\n");
}
document.insertString(context.getTailOffset(), sb);
context.getEditor().getCaretModel().moveToOffset(caret);
}
}), 1.d / keyword.length());
}
}
}