Merge pull request #1507 from eclipse/cd_xtext_issue1777

[eclipse/xtext#1777] ported more xtend code to java

org.eclipse.xtext.ide/src/org/eclipse/xtext/ide/server/contentassist/ContentAssistService.java

@@ -0,0 +1,201 @@
+/**
+ * Copyright (c) 2016, 2020 TypeFox GmbH (http://www.typefox.io) and others.
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0.
+ * 
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package org.eclipse.xtext.ide.server.contentassist;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.concurrent.ExecutorService;
+
+import org.eclipse.lsp4j.CompletionItem;
+import org.eclipse.lsp4j.CompletionItemKind;
+import org.eclipse.lsp4j.CompletionList;
+import org.eclipse.lsp4j.CompletionParams;
+import org.eclipse.lsp4j.InsertTextFormat;
+import org.eclipse.lsp4j.Position;
+import org.eclipse.lsp4j.Range;
+import org.eclipse.lsp4j.TextEdit;
+import org.eclipse.xtext.ide.editor.contentassist.ContentAssistContext;
+import org.eclipse.xtext.ide.editor.contentassist.ContentAssistEntry;
+import org.eclipse.xtext.ide.editor.contentassist.IIdeContentProposalAcceptor;
+import org.eclipse.xtext.ide.editor.contentassist.IdeContentProposalAcceptor;
+import org.eclipse.xtext.ide.editor.contentassist.IdeContentProposalProvider;
+import org.eclipse.xtext.ide.editor.contentassist.antlr.ContentAssistContextFactory;
+import org.eclipse.xtext.ide.server.Document;
+import org.eclipse.xtext.resource.XtextResource;
+import org.eclipse.xtext.service.OperationCanceledManager;
+import org.eclipse.xtext.util.CancelIndicator;
+import org.eclipse.xtext.util.ReplaceRegion;
+import org.eclipse.xtext.util.TextRegion;
+import org.eclipse.xtext.xbase.lib.Exceptions;
+
+import com.google.common.base.Strings;
+import com.google.inject.Inject;
+import com.google.inject.Provider;
+import com.google.inject.Singleton;
+
+/**
+ * @author kosyakov - Initial contribution and API
+ * @author Dennis Huebner - additionalTextEdits support
+ * 
+ * @since 2.11
+ */
+@Singleton
+public class ContentAssistService {
+	public final static int DEFAULT_PROPOSALS_LIMIT = 1000;
+
+	@Inject
+	private Provider<ContentAssistContextFactory> contextFactoryProvider;
+
+	@Inject
+	private ExecutorService executorService;
+
+	@Inject
+	private IdeContentProposalProvider proposalProvider;
+
+	@Inject
+	private Provider<IdeContentProposalAcceptor> proposalAcceptorProvider;
+
+	@Inject
+	private OperationCanceledManager operationCanceledManager;
+
+	public CompletionList createCompletionList(Document document, XtextResource resource, CompletionParams params,
+			CancelIndicator cancelIndicator) {
+		try {
+			CompletionList result = new CompletionList();
+			result.setIsIncomplete(true);
+			IdeContentProposalAcceptor acceptor = proposalAcceptorProvider.get();
+			int caretOffset = document.getOffSet(params.getPosition());
+			Position caretPosition = params.getPosition();
+			TextRegion position = new TextRegion(caretOffset, 0);
+			try {
+				createProposals(document.getContents(), position, caretOffset, resource, acceptor);
+			} catch (Throwable t) {
+				if (!operationCanceledManager.isOperationCanceledException(t)) {
+					throw t;
+				}
+			}
+			int idx = 0;
+			for (ContentAssistEntry it : acceptor.getEntries()) {
+				CompletionItem item = toCompletionItem(it, caretOffset, caretPosition, document);
+				item.setSortText(Strings.padStart(Integer.toString(idx), 5, '0'));
+				result.getItems().add(item);
+				idx++;
+			}
+			return result;
+		} catch (Throwable e) {
+			throw Exceptions.sneakyThrow(e);
+		}
+	}
+
+	protected void createProposals(String document, TextRegion selection, int caretOffset, XtextResource resource,
+			IIdeContentProposalAcceptor acceptor) {
+		if (caretOffset > document.length()) {
+			return;
+		}
+		ContentAssistContextFactory contextFactory = contextFactoryProvider.get();
+		contextFactory.setPool(executorService);
+		ContentAssistContext[] contexts = contextFactory.create(document, selection, caretOffset, resource);
+		proposalProvider.createProposals(Arrays.asList(contexts), acceptor);
+	}
+
+	protected CompletionItem toCompletionItem(ContentAssistEntry entry, int caretOffset, Position caretPosition,
+			Document document) {
+		CompletionItem completionItem = new CompletionItem();
+		String label = entry.getLabel();
+		if (label == null) {
+			label = entry.getProposal();
+		}
+		completionItem.setLabel(label);
+		completionItem.setDetail(entry.getDescription());
+		completionItem.setDocumentation(entry.getDocumentation());
+		String prefix = entry.getPrefix();
+		if (prefix == null) {
+			prefix = "";
+		}
+		int prefixOffset = caretOffset - prefix.length();
+		Position prefixPosition = document.getPosition(prefixOffset);
+		completionItem.setTextEdit(new TextEdit(new Range(prefixPosition, caretPosition), entry.getProposal()));
+		completionItem.setKind(translateKind(entry));
+		if (!entry.getTextReplacements().isEmpty()) {
+			if (completionItem.getAdditionalTextEdits() == null) {
+				completionItem.setAdditionalTextEdits(new ArrayList<>(entry.getTextReplacements().size()));
+			}
+			entry.getTextReplacements().forEach(
+					(ReplaceRegion it) -> completionItem.getAdditionalTextEdits().add(toTextEdit(it, document)));
+		}
+		if (ContentAssistEntry.KIND_SNIPPET.equals(entry.getKind())) {
+			completionItem.setInsertTextFormat(InsertTextFormat.Snippet);
+		}
+		return completionItem;
+	}
+
+	protected CompletionItemKind translateKind(ContentAssistEntry entry) {
+		if (entry.getKind() != null) {
+			switch (entry.getKind()) {
+			case ContentAssistEntry.KIND_CLASS:
+				return CompletionItemKind.Class;
+			case ContentAssistEntry.KIND_COLOR:
+				return CompletionItemKind.Color;
+			case ContentAssistEntry.KIND_CONSTRUCTOR:
+				return CompletionItemKind.Constructor;
+			case ContentAssistEntry.KIND_ENUM:
+				return CompletionItemKind.Enum;
+			case ContentAssistEntry.KIND_FIELD:
+				return CompletionItemKind.Field;
+			case ContentAssistEntry.KIND_FILE:
+				return CompletionItemKind.File;
+			case ContentAssistEntry.KIND_FUNCTION:
+				return CompletionItemKind.Function;
+			case ContentAssistEntry.KIND_INTERFACE:
+				return CompletionItemKind.Interface;
+			case ContentAssistEntry.KIND_KEYWORD:
+				return CompletionItemKind.Keyword;
+			case ContentAssistEntry.KIND_METHOD:
+				return CompletionItemKind.Method;
+			case ContentAssistEntry.KIND_MODULE:
+				return CompletionItemKind.Module;
+			case ContentAssistEntry.KIND_PROPERTY:
+				return CompletionItemKind.Property;
+			case ContentAssistEntry.KIND_REFERENCE:
+				return CompletionItemKind.Reference;
+			case ContentAssistEntry.KIND_SNIPPET:
+				return CompletionItemKind.Snippet;
+			case ContentAssistEntry.KIND_TEXT:
+				return CompletionItemKind.Text;
+			case ContentAssistEntry.KIND_UNIT:
+				return CompletionItemKind.Unit;
+			case ContentAssistEntry.KIND_VALUE:
+				return CompletionItemKind.Value;
+			case ContentAssistEntry.KIND_VARIABLE:
+				return CompletionItemKind.Variable;
+			default:
+				return CompletionItemKind.Value;
+			}
+		} else {
+			return CompletionItemKind.Value;
+		}
+	}
+
+	protected TextEdit toTextEdit(ReplaceRegion region, Document doc) {
+		Position start = null;
+		if (region.getOffset() > doc.getContents().length()) {
+			Position docEnd = doc.getPosition(doc.getContents().length());
+			start = new Position(docEnd.getLine(), docEnd.getCharacter() + region.getLength());
+		} else {
+			start = doc.getPosition(region.getOffset());
+		}
+		Position end = null;
+		if (region.getEndOffset() > doc.getContents().length()) {
+			end = new Position(start.getLine(), start.getCharacter() + region.getLength());
+		} else {
+			end = doc.getPosition(region.getEndOffset());
+		}
+		return new TextEdit(new Range(start, end), region.getText());
+	}
+}