Re-apply apache#7505 that was reverted by apache#7528 with additional…

… resolved.getDocumentation() can be null

ide/lsp.client/src/org/netbeans/modules/lsp/client/bindings/AbstractCompletionItem.java

@@ -0,0 +1,220 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.netbeans.modules.lsp.client.bindings;
+
+import java.awt.Color;
+import java.awt.Font;
+import java.awt.Graphics;
+import java.awt.event.KeyEvent;
+import java.net.URL;
+import java.util.List;
+import java.util.function.Supplier;
+import javax.swing.Action;
+import javax.swing.ImageIcon;
+import javax.swing.text.BadLocationException;
+import javax.swing.text.Document;
+import javax.swing.text.JTextComponent;
+import javax.swing.text.StyledDocument;
+import org.netbeans.api.editor.completion.Completion;
+import org.netbeans.editor.BaseDocument;
+import org.netbeans.editor.Utilities;
+import org.netbeans.spi.editor.completion.CompletionDocumentation;
+import org.netbeans.spi.editor.completion.CompletionItem;
+import org.netbeans.spi.editor.completion.CompletionResultSet;
+import org.netbeans.spi.editor.completion.CompletionTask;
+import org.netbeans.spi.editor.completion.support.AsyncCompletionQuery;
+import org.netbeans.spi.editor.completion.support.AsyncCompletionTask;
+import org.netbeans.spi.editor.completion.support.CompletionUtilities;
+import org.openide.text.NbDocument;
+import org.openide.util.Exceptions;
+
+abstract class AbstractCompletionItem<Edit> implements CompletionItem {
+    private final Document doc;
+    private final int caretOffset;
+    private final String leftLabel;
+    private final String rightLabel;
+    private final ImageIcon icon;
+    private final String sortText;
+    private final String insert;
+
+    AbstractCompletionItem(
+        Document doc, int caretOffset, String leftLabel, String rightLabel,
+        ImageIcon icon, String sortText, String insert
+    ) {
+        this.doc = doc;
+        this.caretOffset = caretOffset;
+        this.leftLabel = leftLabel;
+        this.rightLabel = rightLabel;
+        this.icon = icon;
+        this.sortText = sortText;
+        this.insert = insert;
+    }
+
+    abstract Edit findEdit(boolean[] hideImmediately);
+    abstract int findStart(Document doc, Edit te);
+    abstract int findEnd(Document doc, Edit te);
+    abstract String findNewText(Edit te);
+
+    abstract boolean isTextEdit(Edit te);
+
+    abstract List<String> getCommitCharacters();
+    abstract boolean isTriggerCharacter(String ch);
+    abstract Supplier<String[]> resolveDocumentation(Document doc, int caretOffset);
+
+    @Override
+    public void defaultAction(JTextComponent jtc) {
+        commit("");
+    }
+
+    private void commit(String appendText) {
+        boolean[] hideNow = { false };
+        Edit te = findEdit(hideNow);
+        if (hideNow[0]) {
+            Completion.get().hideDocumentation();
+            Completion.get().hideCompletion();
+            return;
+        }
+        NbDocument.runAtomic((StyledDocument) doc, () -> {
+            try {
+                int endPos;
+                if (isTextEdit(te)) {
+                    int start = findStart(doc, te);
+                    int end = findEnd(doc, te);
+                    doc.remove(start, end - start);
+                    String newText = findNewText(te);
+                    doc.insertString(start, newText, null);
+                    endPos = start + newText.length();
+                } else {
+                    String toAdd = insert;
+                    int[] identSpan = Utilities.getIdentifierBlock((BaseDocument) doc, caretOffset);
+                    if (identSpan != null) {
+                        doc.remove(identSpan[0], identSpan[1] - identSpan[0]);
+                        doc.insertString(identSpan[0], toAdd, null);
+                        endPos = identSpan[0] + toAdd.length();
+                    } else {
+                        doc.insertString(caretOffset, toAdd, null);
+                        endPos = caretOffset + toAdd.length();
+                    }
+                }
+                doc.insertString(endPos, appendText, null);
+            } catch (BadLocationException ex) {
+                Exceptions.printStackTrace(ex);
+            }
+        });
+        Completion.get().hideDocumentation();
+        Completion.get().hideCompletion();
+    }
+
+    @Override
+    public void processKeyEvent(KeyEvent ke) {
+        if (ke.getID() == KeyEvent.KEY_TYPED) {
+            String commitText = String.valueOf(ke.getKeyChar());
+            List<String> commitCharacters = getCommitCharacters();
+            if (commitCharacters != null && commitCharacters.contains(commitText)) {
+                commit(commitText);
+                ke.consume();
+                if (isTriggerCharacter(commitText)) {
+                    Completion.get().showCompletion();
+                }
+            }
+        }
+    }
+
+    @Override
+    public int getPreferredWidth(Graphics grphcs, Font font) {
+        return CompletionUtilities.getPreferredWidth(leftLabel, rightLabel, grphcs, font);
+    }
+
+    @Override
+    public void render(Graphics grphcs, Font font, Color color, Color color1, int i, int i1, boolean bln) {
+        CompletionUtilities.renderHtml(icon, leftLabel, rightLabel, grphcs, font, color, i, i1, bln);
+    }
+
+    @Override
+    public CompletionTask createDocumentationTask() {
+        return new AsyncCompletionTask(new AsyncCompletionQuery() {
+            @Override
+            protected void query(CompletionResultSet resultSet, Document doc, int caretOffset) {
+                Supplier<String[]> resolved = resolveDocumentation(doc, caretOffset);
+                if (resolved != null) {
+                    resultSet.setDocumentation(new CompletionDocumentation() {
+                        @Override
+                        public String getText() {
+                            String[] both = resolved.get();
+                            String detail = both[0];
+                            String content = both[1];
+
+                            StringBuilder documentation = new StringBuilder();
+                            documentation.append("<html>\n");
+                            if (detail != null) {
+                                documentation.append("<b>").append(CompletionProviderImpl.escape(detail)).append("</b>");
+                                documentation.append("\n<p>");
+                            }
+                            if (content != null) {
+                                documentation.append(content);
+                            }
+                            return documentation.toString();
+                        }
+
+                        @Override
+                        public URL getURL() {
+                            return null;
+                        }
+
+                        @Override
+                        public CompletionDocumentation resolveLink(String link) {
+                            return null;
+                        }
+
+                        @Override
+                        public Action getGotoSourceAction() {
+                            return null;
+                        }
+                    });
+                }
+                resultSet.finish();
+            }
+        });
+    }
+
+    @Override
+    public CompletionTask createToolTipTask() {
+        return null;
+    }
+
+    @Override
+    public boolean instantSubstitution(JTextComponent jtc) {
+        return false;
+    }
+
+    @Override
+    public int getSortPriority() {
+        return 100;
+    }
+
+    @Override
+    public CharSequence getSortText() {
+        return sortText;
+    }
+
+    @Override
+    public CharSequence getInsertPrefix() {
+        return insert;
+    }
+}