// Copyright 2017 Google Inc.
//
// 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
//
// https://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 com.google.devtools.intellij.ijaas.handlers;
import com.google.common.collect.Ordering;
import com.google.common.util.concurrent.SettableFuture;
import com.google.devtools.intellij.ijaas.BaseHandler;
import com.google.devtools.intellij.ijaas.handlers.JavaCompleteHandler.Request;
import com.google.devtools.intellij.ijaas.handlers.JavaCompleteHandler.Response;
import com.intellij.codeInsight.completion.CodeCompletionHandlerBase;
import com.intellij.codeInsight.completion.CompletionPhase;
import com.intellij.codeInsight.completion.CompletionProgressIndicator;
import com.intellij.codeInsight.completion.CompletionType;
import com.intellij.codeInsight.completion.impl.CompletionServiceImpl;
import com.intellij.codeInsight.lookup.LookupElement;
import com.intellij.codeInsight.lookup.LookupElementPresentation;
import com.intellij.codeInsight.lookup.impl.LookupImpl;
import com.intellij.lang.java.JavaLanguage;
import com.intellij.openapi.application.Application;
import com.intellij.openapi.application.ApplicationManager;
import com.intellij.openapi.command.CommandProcessor;
import com.intellij.openapi.editor.Editor;
import com.intellij.openapi.editor.EditorFactory;
import com.intellij.openapi.project.Project;
import com.intellij.openapi.project.ProjectLocator;
import com.intellij.openapi.util.Ref;
import com.intellij.openapi.util.io.FileUtil;
import com.intellij.openapi.vfs.LocalFileSystem;
import com.intellij.openapi.vfs.VirtualFile;
import com.intellij.psi.PsiClass;
import com.intellij.psi.PsiDocumentManager;
import com.intellij.psi.PsiElement;
import com.intellij.psi.PsiFile;
import com.intellij.psi.PsiFileFactory;
import com.intellij.psi.PsiKeyword;
import com.intellij.psi.PsiMethod;
import com.intellij.psi.PsiVariable;
import java.io.File;
import java.util.ArrayList;
import java.util.Collections;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.atomic.AtomicReference;
import javax.annotation.Nullable;
public class JavaCompleteHandler extends BaseHandler<Request, Response> {
@Override
protected Class<Request> requestClass() {
return Request.class;
}
@Override
protected Response handle(Request request) {
Project project = findProject(request.file);
if (project == null) {
throw new RuntimeException("Cannot find the target project");
}
SettableFuture<Response> responseFuture = SettableFuture.create();
Application application = ApplicationManager.getApplication();
Ref<PsiFile> psiFileRef = new Ref<>();
application.runReadAction(
() -> {
psiFileRef.set(
PsiFileFactory.getInstance(project)
.createFileFromText(JavaLanguage.INSTANCE, request.text));
});
PsiFile psiFile = psiFileRef.get();
application.invokeAndWait(
() -> {
Editor editor =
EditorFactory.getInstance()
.createEditor(
PsiDocumentManager.getInstance(project).getDocument(psiFile), project);
editor.getCaretModel().moveToOffset(request.offset);
CommandProcessor.getInstance()
.executeCommand(
project,
() -> {
CodeCompletionHandlerBase handler =
new CodeCompletionHandlerBase(CompletionType.BASIC) {
@Override
protected void completionFinished(
CompletionProgressIndicator indicator, boolean hasModifiers) {
CompletionServiceImpl.setCompletionPhase(
new CompletionPhase.ItemsCalculated(indicator));
Response response = new Response();
LookupImpl lookup = indicator.getLookup();
for (LookupElement item : lookup.getItems()) {
PsiElement psi = item.getPsiElement();
if (psi == null) {
continue;
}
Completion c = new Completion();
LookupElementPresentation presentation =
new LookupElementPresentation();
item.renderElement(presentation);
c.word =
item.getLookupString().substring(lookup.getPrefixLength(item));
if (psi instanceof PsiMethod) {
PsiMethod m = (PsiMethod) psi;
if (m.getParameterList().getParametersCount() == 0) {
c.word += "()";
} else {
c.word += '(';
}
c.menu =
presentation.getTypeText() + " - " + presentation.getTailText();
c.kind = Completion.FUNCTION;
} else if (psi instanceof PsiKeyword) {
c.kind = Completion.KEYWORD;
} else if (psi instanceof PsiClass) {
c.menu = presentation.getTailText();
c.kind = Completion.TYPE;
} else if (psi instanceof PsiVariable) {
c.menu = presentation.getTypeText();
c.kind = Completion.VARIABLE;
} else {
c.menu = psi.getClass().getSimpleName();
c.kind = "";
}
response.completions.add(c);
}
responseFuture.set(response);
}
};
handler.invokeCompletion(project, editor);
},
null,
null);
});
try {
Response response = responseFuture.get();
Collections.sort(response.completions, new CompletionOrdering());
return response;
} catch (ExecutionException e) {
throw new RuntimeException(e);
} catch (InterruptedException e) {
Thread.currentThread().interrupt();
throw new RuntimeException(e);
}
}
@Nullable
private Project findProject(String file) {
LocalFileSystem localFileSystem = LocalFileSystem.getInstance();
ProjectLocator projectLocator = ProjectLocator.getInstance();
AtomicReference<Project> ret = new AtomicReference<>();
FileUtil.processFilesRecursively(
new File(file),
(f) -> {
VirtualFile vf = localFileSystem.findFileByIoFile(f);
if (vf != null) {
ret.set(projectLocator.guessProjectForFile(vf));
return false;
}
return true;
});
return ret.get();
}
public static class Request {
String file;
String text;
int offset;
}
public static class Response {
ArrayList<Completion> completions = new ArrayList<>();
}
public class Completion {
public static final String VARIABLE = "v";
public static final String FUNCTION = "f";
public static final String TYPE = "t";
public static final String KEYWORD = "k";
public String word;
public String menu;
public String kind;
}
private static class CompletionOrdering extends Ordering<Completion> {
@Override
public int compare(Completion arg0, Completion arg1) {
boolean arg0Keyword = arg0.kind.equals(Completion.KEYWORD);
boolean arg1Keyword = arg1.kind.equals(Completion.KEYWORD);
if (arg0Keyword && !arg1Keyword) {
return 1;
} else if (!arg0Keyword && arg1Keyword) {
return -1;
}
return arg0.word.compareTo(arg1.word);
}
}
}
