add dart: and package: import uri suggestions

pkg/analysis_server/lib/src/services/completion/import_uri_contributor.dart

Index: pkg/analysis_server/lib/src/services/completion/import_uri_contributor.dart
diff --git a/pkg/analysis_server/lib/src/services/completion/import_uri_contributor.dart b/pkg/analysis_server/lib/src/services/completion/import_uri_contributor.dart
new file mode 100644
index 0000000000000000000000000000000000000000..1aeaa46fecdf439c85a3cae5cc8d02757d2b36cc
--- /dev/null
+++ b/pkg/analysis_server/lib/src/services/completion/import_uri_contributor.dart
@@ -0,0 +1,134 @@
+// Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+library services.completion.contributor.dart.importuri;
+
+import 'dart:async';
+import 'dart:collection';
+
+import 'package:analysis_server/src/services/completion/dart_completion_manager.dart';
+import 'package:analysis_server/src/services/completion/local_declaration_visitor.dart';
+import 'package:analysis_server/src/services/completion/local_suggestion_builder.dart';
+import 'package:analysis_server/src/services/completion/optype.dart';
+import 'package:analysis_server/src/services/completion/suggestion_builder.dart';
+import 'package:analyzer/file_system/file_system.dart';
+import 'package:analyzer/src/generated/ast.dart';
+import 'package:analyzer/src/generated/element.dart';
+import 'package:analyzer/src/generated/sdk.dart';
+import 'package:analyzer/src/generated/source.dart';
+
+import '../../protocol_server.dart'
+    show CompletionSuggestion, CompletionSuggestionKind;
+import '../../protocol_server.dart' as protocol;
+
+/**
+ * A contributor for calculating uri suggestions for an import directive.
+ */
+class ImportUriContributor extends DartCompletionContributor {
+  _ImportUriSuggestionBuilder builder;
+
+  @override
+  bool computeFast(DartCompletionRequest request) {
+    builder = new _ImportUriSuggestionBuilder(request);
+    return builder.computeFast(request.target.containingNode);
+  }
+
+  @override
+  Future<bool> computeFull(DartCompletionRequest request) {
+    return new Future.value(false);
+  }
+}
+
+class _ImportUriSuggestionBuilder extends SimpleAstVisitor {
+  final DartCompletionRequest request;
+  HashSet<String> _importedUris;
+
+  _ImportUriSuggestionBuilder(this.request);
+
+  bool computeFast(AstNode node) {
+    node.accept(this);
+    return true;
+  }
+
+  @override
+  visitSimpleStringLiteral(SimpleStringLiteral node) {
+    AstNode parent = node.parent;
+    if (parent is ImportDirective && parent.uri == node) {
+      String partial = node.literal.lexeme.substring(
+          node.contentsOffset - node.offset, request.offset - node.offset);
+      _computeImportedUris();
+      request.replacementOffset = node.contentsOffset;
+      request.replacementLength = node.contentsEnd - node.contentsOffset;
+      _addDartSuggestions();
+      _addPackageSuggestions(partial);
+      _addFileSuggestions(partial);
+    }
+  }
+
+  void _addDartSuggestions() {
+    _addSuggestion('dart:');
+    SourceFactory factory = request.context.sourceFactory;
+    for (SdkLibrary lib in factory.dartSdk.sdkLibraries) {
+      if (!lib.isInternal && !lib.isImplementation) {
+        if (!lib.shortName.startsWith('dart:_')) {
+          _addSuggestion(lib.shortName);
+        }
+      }
+    }
+  }
+
+  void _addFileSuggestions(String partial) {
+    // TODO(danrubel) implement
+  }
+
+  void _addFolderSuggestions(String partial, String prefix, Folder folder) {
+    for (Resource child in folder.getChildren()) {
+      if (child is Folder) {
+        String childPrefix = '$prefix${child.shortName}/';
+        _addSuggestion(childPrefix);
+        if (partial.startsWith(childPrefix)) {
+          _addFolderSuggestions(partial, childPrefix, child);
+        }
+      } else {
+        _addSuggestion('$prefix${child.shortName}');
+      }
+    }
+  }
+
+  void _addPackageSuggestions(String partial) {
+    SourceFactory factory = request.context.sourceFactory;
+    Map<String, List<Folder>> packageMap = factory.packageMap;
+    if (packageMap != null) {
+      _addSuggestion('package:');
+      packageMap.forEach((String pkgName, List<Folder> folders) {
+        String prefix = 'package:$pkgName/';
+        _addSuggestion(prefix);
+        for (Folder folder in folders) {
+          _addFolderSuggestions(partial, prefix, folder);
+        }
+      });
+    }
+  }
+
+  void _addSuggestion(String completion) {
+    if (!_importedUris.contains(completion)) {
+      request.addSuggestion(new CompletionSuggestion(
+          CompletionSuggestionKind.IMPORT, DART_RELEVANCE_DEFAULT, completion,
+          completion.length, 0, false, false));
+    }
+  }
+
+  void _computeImportedUris() {
+    _importedUris = new HashSet<String>();
+    _importedUris.add('dart:core');
+    for (Directive directive in request.unit.directives) {
+      if (directive is ImportDirective) {
+        String uri = directive.uriContent;
+        if (uri != null && uri.length > 0) {
+          _importedUris.add(uri);
+        }
+      }
+    }
+  }
+}