Initial Completion support

UpsilonLanguageServer/UpsilonLanguageServer/Services/CompletionItemService.cs

@@ -13,7 +13,7 @@ namespace UpsilonLanguageServer.Services
         {
             var item = RequestContext.Request.Parameters.ToObject<CompletionItem>(Utility.CamelCaseJsonSerializer);
             // Add a pair of square brackets around the inserted text.
-            item.InsertText = $"[{item.Label}]";
+            item.InsertText = item.Label;
             return item;
         }
     }

UpsilonLanguageServer/UpsilonLanguageServer/Services/TextDocumentServer.cs

@@ -1,4 +1,5 @@
 using System.Collections.Generic;
+using System.Linq;
 using System.Text;
 using System.Threading;
 using System.Threading.Tasks;
@@ -108,25 +109,35 @@ namespace UpsilonLanguageServer.Services
             Session.Documents.TryRemove(textDocument.Uri, out _);
         }
 
-        private static readonly CompletionItem[] PredefinedCompletionItems =
-        {
-            new CompletionItem(".NET", CompletionItemKind.Keyword,
-                "Keyword1",
-                "Short for **.NET Framework**, a software framework by Microsoft (possibly its subsets) or later open source .NET Core.",
-                null),
-            new CompletionItem(".NET Standard", CompletionItemKind.Keyword,
-                "Keyword2",
-                "The .NET Standard is a formal specification of .NET APIs that are intended to be available on all .NET runtimes.",
-                null),
-            new CompletionItem(".NET Framework", CompletionItemKind.Keyword,
-                "Keyword3",
-                ".NET Framework (pronounced dot net) is a software framework developed by Microsoft that runs primarily on Microsoft Windows.", null),
-        };
-
         [JsonRpcMethod]
         public async Task<CompletionList> Completion(TextDocumentIdentifier textDocument, Position position, CompletionContext context)
         {
-            return new CompletionList(PredefinedCompletionItems, false);
+            if (Session.Documents.TryGetValue(textDocument.Uri, out var doc) && doc.Bound != null)
+            {
+                if (context.TriggerCharacter == '.')
+                {
+                    var linePos  = doc.SourceText.GetLineStartPos(position.Line);
+                    var findNode = doc.Bound.GetNodeAtPosition(linePos + position.Character - 2);
+                    if (findNode is BoundVariableSymbol variableSymbol)
+                    {
+                        if (variableSymbol.VariableSymbol is TableVariableSymbol tableSymbol)
+                        {
+                            return new CompletionList(
+                                tableSymbol.Variables.Select(x => new CompletionItem(x.Name,
+                                    CompletionItemKind.Variable, x.Type.ToString(),
+                                    $"\n\n{string.Join("  \n", x.CommentValue)}")));
+                        }
+                        return new CompletionList(
+                            new[]
+                            {
+                                new CompletionItem(findNode.Kind.ToString(), CompletionItemKind.Variable,
+                                    variableSymbol.VariableSymbol.Name, ""),
+                            },
+                            false);
+                    }
+                }
+            }
+            return new CompletionList(new CompletionItem[0], false);
         }
 
     }