try catch all the things

Reviewed-on: #4

BLL/CommitDetail.cs

@@ -93,12 +93,20 @@ public class CommitDetail
         {
             var branchResult = repo.Branches[branchName];
 
+            try
+            {
                 if (branchResult == null)
                 {
                     branchResult = repo.Branches[$"origin/{branchName}"];
                     var remoteBranch = repo.CreateBranch(branchName, branchResult.Tip);
                     repo.Branches.Update(remoteBranch, b => b.UpstreamBranch = $"refs/heads/{branchName}");
                 }   
+            }
+            catch (System.Exception)
+            {
+                Console.WriteLine($"Cannot fetch {branchName} branch.");
+                Environment.Exit(1);
+            }
 
             foreach (var c in branchResult.Commits)
             {
@@ -120,8 +128,36 @@ public class CommitDetail
     {
         using (var repo = new Repository(Directory.GetCurrentDirectory()))
         {
-            var tagResult = repo.Tags[tagName];
+            try
-            System.Console.WriteLine(tagResult);
+            {
+                var tagResult = repo.Tags[tagName].Target.Sha;
+                
+                var commitFilter = new CommitFilter
+                {
+                    IncludeReachableFrom = tagResult,
+                };
+
+                var query = repo.Commits.QueryBy(commitFilter);
+
+                foreach (var c in query)
+                {
+                    if (!_authors.Contains(c.Author.Name))
+                    {
+                        _authors.Add(c.Author.Name);
+                    }
+                }
+
+                foreach (var a in _authors)
+                {
+                    int commitCount = query.Where(r => r.Author.Name == a).Count();
+                    _commitDetails.Add(a, commitCount);
+                }
+            }
+            catch (System.Exception)
+            {
+                Console.WriteLine($"Cannot find the tag {tagName}");
+                Environment.Exit(3);
+            }
         }
     }
 }

Program.cs

@@ -16,13 +16,20 @@ static class Program
                 );
         branchOption.AddAlias("-b");
 
+        var tagOption = new Option<string>(
+                "--tag",
+                "Specify the tag to filter by"
+                );
+        tagOption.AddAlias("-t");
+
         var rootCommand = new RootCommand("Get a tally of contributors' commits")
         {
             outputOption,
             branchOption,
+            tagOption,
         };
 
-        rootCommand.SetHandler((outputOptionValue, branchOptionValue) => {
+        rootCommand.SetHandler((outputOptionValue, branchOptionValue, tagOptionValue) => {
                     CommitDetail commits = new CommitDetail();
                     
                     switch (outputOptionValue) 
@@ -31,6 +38,10 @@ static class Program
                             StdOutDataService outDataService = new StdOutDataService();
                             DataAccess dataAccess = new DataAccess(outDataService);
 
+                            if (branchOptionValue != null && tagOptionValue != null) {
+                                Console.WriteLine("Please specify either a branch or a tag");
+                                Environment.Exit(2);
+                            } else if (branchOptionValue != null && tagOptionValue == null) {
                                 switch (branchOptionValue)
                                 {
                                     case null:
@@ -43,10 +54,19 @@ static class Program
                                         break;
                                 }
                                 break;
+                            } else if (branchOptionValue == null && tagOptionValue != null) {
+                                commits.GetCommitsByTag(tagOptionValue);
+                                dataAccess.WriteData(commits.CommitDetails);
+                            }
+                            break;
                         case "xlsx":
                             ExcelDataService excelDataService = new ExcelDataService();
                             DataAccess dataAccessExcelCase = new DataAccess(excelDataService);
 
+                            if (branchOptionValue != null && tagOptionValue != null) {
+                                Console.WriteLine("Please specify either a branch or a tag.");
+                                Environment.Exit(2);
+                            } else if (branchOptionValue != null && tagOptionValue == null) {
                                 switch (branchOptionValue)
                                 {
                                     case null:
@@ -59,6 +79,11 @@ static class Program
                                         break;
                                 }
                                 break;
+                            } else if (branchOptionValue == null && tagOptionValue != null) {
+                                commits.GetCommitsByTag(tagOptionValue);
+                                dataAccessExcelCase.WriteData(commits.CommitDetails);
+                            }
+                            break;
                         case "pdf":
                             PdfDataService pdfDataService = new PdfDataService();
                             DataAccess dataAccessPdfCase = new DataAccess(pdfDataService);
@@ -79,6 +104,10 @@ static class Program
                             StdOutDataService stdOutDataService = new StdOutDataService();
                             DataAccess dataAccessNullCase = new DataAccess(stdOutDataService);
 
+                            if (branchOptionValue != null && tagOptionValue != null) {
+                                Console.WriteLine("Please specify either a branch or a tag.");
+                                Environment.Exit(2);
+                            } else if (branchOptionValue != null && tagOptionValue == null) {
                                 switch (branchOptionValue)
                                 {
                                     case null:
@@ -91,13 +120,21 @@ static class Program
                                         break;
                                 }
                                 break;
+                            } else if (branchOptionValue == null && tagOptionValue != null) {
+                                commits.GetCommitsByTag(tagOptionValue);
+                                dataAccessNullCase.WriteData(commits.CommitDetails);
+                            } else {
+                                commits.GetCurrentCommitsByName();
+                                dataAccessNullCase.WriteData(commits.CommitDetails);
+                            }
+                            break;
                         default:
                             System.Console.WriteLine("This should not happen...");
-                            Environment.Exit(90);
+                            Environment.Exit(4);
                             break;
                     }
                 },
-                outputOption, branchOption);
+                outputOption, branchOption, tagOption);
 
         rootCommand.Invoke(args);
     }