Allow navigation to comment on GitHub.

When the date in a comment is clicked, navigate to the comment on GitHub.

Author: grokys

src/GitHub.InlineReviews/GitHub.InlineReviews.csproj

@@ -196,6 +196,10 @@
       <Project>{6AFE2E2D-6DB0-4430-A2EA-F5F5388D2F78}</Project>
       <Name>GitHub.Extensions</Name>
     </ProjectReference>
+    <ProjectReference Include="..\GitHub.UI.Reactive\GitHub.UI.Reactive.csproj">
+      <Project>{158b05e8-fdbc-4d71-b871-c96e28d5adf5}</Project>
+      <Name>GitHub.UI.Reactive</Name>
+    </ProjectReference>
     <ProjectReference Include="..\GitHub.UI\GitHub.UI.csproj">
       <Project>{346384dd-2445-4a28-af22-b45f3957bd89}</Project>
       <Name>GitHub.UI</Name>

src/GitHub.InlineReviews/SampleData/CommentThreadViewModelDesigner.cs

@@ -16,5 +16,10 @@ class CommentThreadViewModelDesigner : ICommentThreadViewModel
             = new AccountDesigner { Login = "shana", IsUser = true };
 
         public ReactiveCommand<ICommentModel> PostComment { get; }
+
+        public Uri GetCommentUrl(int id)
+        {
+            throw new NotImplementedException();
+        }
     }
 }

src/GitHub.InlineReviews/SampleData/CommentViewModelDesigner.cs

@@ -3,27 +3,34 @@
 using GitHub.InlineReviews.ViewModels;
 using GitHub.Models;
 using GitHub.SampleData;
+using GitHub.UI;
 using ReactiveUI;
 
 namespace GitHub.InlineReviews.SampleData
 {
-    class CommentViewModelDesigner : ICommentViewModel
+    class CommentViewModelDesigner : ReactiveObject, ICommentViewModel
     {
         public CommentViewModelDesigner()
         {
             User = new AccountDesigner { Login = "shana", IsUser = true };
         }
 
+        public void Initialize(ViewWithData data)
+        {
+        }
+
         public int Id { get; set; }
         public string Body { get; set; }
         public string ErrorMessage { get; set; }
         public CommentEditState EditState { get; set; }
         public bool IsReadOnly { get; set; }
+        public ICommentThreadViewModel Thread { get; }
         public DateTimeOffset UpdatedAt => DateTime.Now.Subtract(TimeSpan.FromDays(3));
         public IAccount User { get; set; }
 
         public ReactiveCommand<object> BeginEdit { get; }
         public ReactiveCommand<object> CancelEdit { get; }
         public ReactiveCommand<Unit> CommitEdit { get; }
+        public ReactiveCommand<object> OpenOnGitHub { get; }
     }
 }

src/GitHub.InlineReviews/ViewModels/CommentThreadViewModel.cs

@@ -54,6 +54,9 @@ public void Dispose()
             GC.SuppressFinalize(this);
         }
 
+        /// <inheritdoc/>
+        public abstract Uri GetCommentUrl(int id);
+
         protected virtual void Dispose(bool disposing)
         {
             if (disposing)

src/GitHub.InlineReviews/ViewModels/CommentViewModel.cs

@@ -5,6 +5,7 @@
 using System.Threading.Tasks;
 using GitHub.Extensions;
 using GitHub.Models;
+using GitHub.UI;
 using ReactiveUI;
 
 namespace GitHub.InlineReviews.ViewModels
@@ -73,6 +74,8 @@ public CommentViewModel(
             CancelEdit = ReactiveCommand.Create(CommitEdit.IsExecuting.Select(x => !x));
             CancelEdit.Subscribe(DoCancelEdit);
             AddErrorHandler(CancelEdit);
+
+            OpenOnGitHub = ReactiveCommand.Create(this.WhenAnyValue(x => x.Id, x => x != 0));
         }
 
         /// <summary>
@@ -89,6 +92,11 @@ public CommentViewModel(
         {
         }
 
+        public void Initialize(ViewWithData data)
+        {
+            // Nothing to do here: initialized in constructor.
+        }
+
         /// <summary>
         /// Creates a placeholder comment which can be used to add a new comment to a thread.
         /// </summary>
@@ -208,5 +216,8 @@ public DateTimeOffset UpdatedAt
 
         /// <inheritdoc/>
         public ReactiveCommand<Unit> CommitEdit { get; }
+
+        /// <inheritdoc/>
+        public ReactiveCommand<object> OpenOnGitHub { get; }
     }
 }

src/GitHub.InlineReviews/ViewModels/ICommentThreadViewModel.cs

@@ -10,6 +10,13 @@ namespace GitHub.InlineReviews.ViewModels
     /// </summary>
     public interface ICommentThreadViewModel
     {
+        /// <summary>
+        /// Gets the browser URI for a comment in the thread.
+        /// </summary>
+        /// <param name="id">The ID of the comment.</param>
+        /// <returns>The URI.</returns>
+        Uri GetCommentUrl(int id);
+
         /// <summary>
         /// Gets the comments in the thread.
         /// </summary>

src/GitHub.InlineReviews/ViewModels/ICommentViewModel.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Reactive;
 using GitHub.Models;
+using GitHub.ViewModels;
 using ReactiveUI;
 
 namespace GitHub.InlineReviews.ViewModels
@@ -12,7 +13,7 @@ public enum CommentEditState
         Placeholder,
     }
 
-    public interface ICommentViewModel
+    public interface ICommentViewModel : IViewModel
     {
         /// <summary>
         /// Gets the ID of the comment.
@@ -49,6 +50,11 @@ public interface ICommentViewModel
         /// </summary>
         IAccount User { get; }
 
+        /// <summary>
+        /// Gets the thread that the comment is a part of.
+        /// </summary>
+        ICommentThreadViewModel Thread { get; }
+
         /// <summary>
         /// Gets a command which will begin editing of the comment.
         /// </summary>
@@ -63,5 +69,10 @@ public interface ICommentViewModel
         /// Gets a command which will commit edits to the comment.
         /// </summary>
         ReactiveCommand<Unit> CommitEdit { get; }
+
+        /// <summary>
+        /// Gets a command to open the comment in a browser.
+        /// </summary>
+        ReactiveCommand<object> OpenOnGitHub { get; }
     }
 }

src/GitHub.InlineReviews/ViewModels/InlineCommentThreadViewModel.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Globalization;
 using System.Reactive.Linq;
 using System.Threading.Tasks;
 using GitHub.Api;
@@ -34,6 +35,7 @@ public InlineCommentThreadViewModel(
 
             this.apiClient = apiClient;
             Session = session;
+
             PostComment = ReactiveCommand.CreateAsyncTask(
                 Observable.Return(true),
                 DoPostComment);
@@ -51,6 +53,17 @@ public InlineCommentThreadViewModel(
         /// </summary>
         public IPullRequestSession Session { get; }
 
+        /// <inheritdoc/>
+        public override Uri GetCommentUrl(int id)
+        {
+            return new Uri(string.Format(
+                CultureInfo.InvariantCulture,
+                "{0}/pull/{1}#discussion_r{2}",
+                Session.Repository.CloneUrl.ToRepositoryUrl(),
+                Session.PullRequest.Number,
+                id));
+        }
+
         async Task<ICommentModel> DoPostComment(object parameter)
         {
             Guard.ArgumentNotNull(parameter, nameof(parameter));

src/GitHub.InlineReviews/ViewModels/IssueCommentThreadViewModel.cs

@@ -17,6 +17,12 @@ public IssueCommentThreadViewModel(
             Number = number;
         }
 
+        /// <inheritdoc/>
+        public override Uri GetCommentUrl(int id)
+        {
+            throw new NotImplementedException();
+        }
+
         public IRepositoryModel Repository { get; }
         public int Number { get; }
     }

src/GitHub.InlineReviews/ViewModels/NewInlineCommentThreadViewModel.cs

@@ -97,6 +97,12 @@ public bool NeedsPush
             private set { this.RaiseAndSetIfChanged(ref needsPush, value); }
         }
 
+        /// <inheritdoc/>
+        public override Uri GetCommentUrl(int id)
+        {
+            throw new NotSupportedException("Cannot navigate to a non-posted comment.");
+        }
+
         async Task<ICommentModel> DoPostComment(object parameter)
         {
             Guard.ArgumentNotNull(parameter, nameof(parameter));