//
// Copyright (c) Microsoft. All rights reserved.
// Licensed under the MIT license. See LICENSE file in the project root for full license information.
//

using System.Threading.Tasks;
using Microsoft.SqlServer.Management.SqlParser.Parser;
using Microsoft.SqlTools.ServiceLayer.Connection;
using Microsoft.SqlTools.ServiceLayer.LanguageServices;
using Microsoft.SqlTools.ServiceLayer.LanguageServices.Completion;
using Microsoft.SqlTools.ServiceLayer.LanguageServices.Contracts;
using Microsoft.SqlTools.ServiceLayer.Test.Common;
using Microsoft.SqlTools.ServiceLayer.Workspace.Contracts;
using Microsoft.SqlTools.Test.Utility;
using Xunit;

namespace Microsoft.SqlTools.ServiceLayer.IntegrationTests.LanguageServer
{
    /// <summary>
    /// Tests for the ServiceHost Language Service tests
    /// </summary>
    public class LanguageServiceTests
    {
        private async static Task<TestConnectionResult> GetLiveAutoCompleteTestObjects()
        {
            var textDocument = new TextDocumentPosition
            {
                TextDocument = new TextDocumentIdentifier { Uri = TestObjects.ScriptUri },
                Position = new Position
                {
                    Line = 0,
                    Character = 0
                }
            };

            var result = await TestObjects.InitLiveConnectionInfo();
            result.TextDocumentPosition = textDocument;
            return result;
        }

        /// <summary>
        /// Test the service initialization code path and verify nothing throws
        /// </summary>
        [Fact]
        public void ServiceInitialization()
        {
            try
            {
                TestServiceProvider.InitializeTestServices();
            }
            catch (System.ArgumentException)
            {

            }
            Assert.True(LanguageService.Instance.Context != null);
            Assert.True(LanguageService.ConnectionServiceInstance != null);
            Assert.True(LanguageService.Instance.CurrentSettings != null);
            Assert.True(LanguageService.Instance.CurrentWorkspace != null);
        }

        /// <summary>
        /// Test the service initialization code path and verify nothing throws
        /// </summary>
        [Fact]
        public async Task PrepopulateCommonMetadata()
        {
            var result = await TestObjects.InitLiveConnectionInfo();
            var connInfo = result.ConnectionInfo;

            ScriptParseInfo scriptInfo = new ScriptParseInfo { IsConnected = true };

            AutoCompleteHelper.PrepopulateCommonMetadata(connInfo, scriptInfo, null);
        }

        // This test currently requires a live database connection to initialize 
        // SMO connected metadata provider.  Since we don't want a live DB dependency
        // in the CI unit tests this scenario is currently disabled.
        [Fact]
        public async Task AutoCompleteFindCompletions()
        {
            var result = await GetLiveAutoCompleteTestObjects();

            result.TextDocumentPosition.Position.Character = 7;
            result.ScriptFile.Contents = "select ";

            var autoCompleteService = LanguageService.Instance;
            var completions = autoCompleteService.GetCompletionItems(
                result.TextDocumentPosition,
                result.ScriptFile,
                result.ConnectionInfo);

            Assert.True(completions.Length > 0);
        }

        /// <summary>
        /// Verify that GetSignatureHelp returns not null when the provided TextDocumentPosition
        /// has an associated ScriptParseInfo and the provided query has a function that should
        /// provide signature help.
        /// </summary>
        [Fact]
        public async Task GetSignatureHelpReturnsNotNullIfParseInfoInitialized()
        {
            // When we make a connection to a live database
            Hosting.ServiceHost.SendEventIgnoreExceptions = true;
            var result = await TestObjects.InitLiveConnectionInfo();

            // And we place the cursor after a function that should prompt for signature help
            string queryWithFunction = "EXEC sys.fn_isrolemember ";
            result.ScriptFile.Contents = queryWithFunction;
            TextDocumentPosition textDocument = new TextDocumentPosition
            {
                TextDocument = new TextDocumentIdentifier
                {
                    Uri = result.ScriptFile.ClientFilePath
                },
                Position = new Position
                {
                    Line = 0,
                    Character = queryWithFunction.Length
                }
            };

            // If the SQL has already been parsed
            var service = LanguageService.Instance;
            await service.UpdateLanguageServiceOnConnection(result.ConnectionInfo);

            // We should get back a non-null ScriptParseInfo
            ScriptParseInfo parseInfo = service.GetScriptParseInfo(result.ScriptFile.ClientFilePath);
            Assert.NotNull(parseInfo);

            // And we should get back a non-null SignatureHelp
            SignatureHelp signatureHelp = service.GetSignatureHelp(textDocument, result.ScriptFile);
            Assert.NotNull(signatureHelp);
        }
    }
}