Refactor resolving chat log to a separate service to allow reusability across CLI and GUI

DiscordChatExporter.Cli/Container.cs

@@ -12,6 +12,7 @@ namespace DiscordChatExporter.Cli
             SimpleIoc.Default.Reset();
 
             // Services
+            SimpleIoc.Default.Register<IChatLogService, ChatLogService>();
             SimpleIoc.Default.Register<IDataService, DataService>();
             SimpleIoc.Default.Register<IExportService, ExportService>();
             SimpleIoc.Default.Register<IMessageGroupService, MessageGroupService>();

DiscordChatExporter.Cli/Verbs/ExportChatVerb.cs

@@ -20,8 +20,7 @@ namespace DiscordChatExporter.Cli.Verbs
             // Get services
             var container = new Container();
             var settingsService = container.Resolve<ISettingsService>();
-            var dataService = container.Resolve<IDataService>();
-            var messageGroupService = container.Resolve<IMessageGroupService>();
+            var chatLogService = container.Resolve<IChatLogService>();
             var exportService = container.Resolve<IExportService>();
 
             // Configure settings
@@ -30,37 +29,20 @@ namespace DiscordChatExporter.Cli.Verbs
             if (Options.MessageGroupLimit > 0)
                 settingsService.MessageGroupLimit = Options.MessageGroupLimit;
 
-            // Get channel and guild
-            var channel = await dataService.GetChannelAsync(Options.GetToken(), Options.ChannelId);
-            var guild = channel.GuildId == Guild.DirectMessages.Id
-                ? Guild.DirectMessages
-                : await dataService.GetGuildAsync(Options.GetToken(), channel.GuildId);
+            // Get chat log
+            var chatLog = await chatLogService.GetChatLogAsync(Options.GetToken(), Options.ChannelId, 
+                Options.After, Options.Before);
 
             // Generate file path if not set
             var filePath = Options.FilePath;
             if (filePath == null || filePath.EndsWith("/") || filePath.EndsWith("\\"))
             {
-                filePath += $"{guild.Name} - {channel.Name}.{Options.ExportFormat.GetFileExtension()}"
+                filePath += $"{chatLog.Guild.Name} - {chatLog.Channel.Name}.{Options.ExportFormat.GetFileExtension()}"
                     .Replace(Path.GetInvalidFileNameChars(), '_');
             }
 
-            // TODO: extract this to make it reusable across implementations
-            // Get messages
-            var messages =
-                await dataService.GetChannelMessagesAsync(Options.GetToken(), channel.Id,
-                    Options.After, Options.Before);
-
-            // Group messages
-            var messageGroups = messageGroupService.GroupMessages(messages);
-
-            // Get mentionables
-            var mentionables = await dataService.GetMentionablesAsync(Options.GetToken(), guild.Id, messages);
-
-            // Create log
-            var log = new ChatLog(guild, channel, Options.After, Options.Before, messageGroups, mentionables);
-
             // Export
-            exportService.Export(Options.ExportFormat, filePath, log);
+            exportService.Export(Options.ExportFormat, filePath, chatLog);
 
             // Print result
             Console.WriteLine($"Exported chat to [{filePath}]");

DiscordChatExporter.Core/Services/ChatLogService.cs

@@ -0,0 +1,48 @@
+using System;
+using System.Threading.Tasks;
+using DiscordChatExporter.Core.Models;
+
+namespace DiscordChatExporter.Core.Services
+{
+    public class ChatLogService : IChatLogService
+    {
+        private readonly IDataService _dataService;
+        private readonly IMessageGroupService _messageGroupService;
+
+        public ChatLogService(IDataService dataService, IMessageGroupService messageGroupService)
+        {
+            _dataService = dataService;
+            _messageGroupService = messageGroupService;
+        }
+
+        public async Task<ChatLog> GetChatLogAsync(AuthToken token, Guild guild, Channel channel,
+            DateTime? from = null, DateTime? to = null, IProgress<double> progress = null)
+        {
+            // Get messages
+            var messages = await _dataService.GetChannelMessagesAsync(token, channel.Id, from, to, progress);
+
+            // Group messages
+            var messageGroups = _messageGroupService.GroupMessages(messages);
+
+            // Get mentionables
+            var mentionables = await _dataService.GetMentionablesAsync(token, guild.Id, messages);
+
+            return new ChatLog(guild, channel, from, to, messageGroups, mentionables);
+        }
+
+        public async Task<ChatLog> GetChatLogAsync(AuthToken token, string channelId,
+            DateTime? from = null, DateTime? to = null, IProgress<double> progress = null)
+        {
+            // Get channel
+            var channel = await _dataService.GetChannelAsync(token, channelId);
+
+            // Get guild
+            var guild = channel.GuildId == Guild.DirectMessages.Id
+                ? Guild.DirectMessages
+                : await _dataService.GetGuildAsync(token, channel.GuildId);
+
+            // Get the chat log
+            return await GetChatLogAsync(token, guild, channel, from, to, progress);
+        }
+    }
+}

DiscordChatExporter.Core/Services/DataService.cs

@@ -65,6 +65,10 @@ namespace DiscordChatExporter.Core.Services
 
         public async Task<Guild> GetGuildAsync(AuthToken token, string guildId)
         {
+            // Special case for direct messages pseudo-guild
+            if (guildId == Guild.DirectMessages.Id)
+                return Guild.DirectMessages;
+
             var response = await GetApiResponseAsync(token, "guilds", guildId);
             var guild = ParseGuild(response);
 

DiscordChatExporter.Core/Services/IChatLogService.cs

@@ -0,0 +1,15 @@
+using System;
+using System.Threading.Tasks;
+using DiscordChatExporter.Core.Models;
+
+namespace DiscordChatExporter.Core.Services
+{
+    public interface IChatLogService
+    {
+        Task<ChatLog> GetChatLogAsync(AuthToken token, Guild guild, Channel channel, 
+            DateTime? from = null, DateTime? to = null, IProgress<double> progress = null);
+
+        Task<ChatLog> GetChatLogAsync(AuthToken token, string channelId,
+            DateTime? from = null, DateTime? to = null, IProgress<double> progress = null);
+    }
+}

DiscordChatExporter.Gui/Container.cs

@@ -17,6 +17,7 @@ namespace DiscordChatExporter.Gui
             SimpleIoc.Default.Reset();
 
             // Services
+            SimpleIoc.Default.Register<IChatLogService, ChatLogService>();
             SimpleIoc.Default.Register<IDataService, DataService>();
             SimpleIoc.Default.Register<IExportService, ExportService>();
             SimpleIoc.Default.Register<IMessageGroupService, MessageGroupService>();

DiscordChatExporter.Gui/ViewModels/MainViewModel.cs

@@ -19,7 +19,7 @@ namespace DiscordChatExporter.Gui.ViewModels
         private readonly ISettingsService _settingsService;
         private readonly IUpdateService _updateService;
         private readonly IDataService _dataService;
-        private readonly IMessageGroupService _messageGroupService;
+        private readonly IChatLogService _chatLogService;
         private readonly IExportService _exportService;
 
         private readonly Dictionary<Guild, IReadOnlyList<Channel>> _guildChannelsMap;
@@ -111,12 +111,12 @@ namespace DiscordChatExporter.Gui.ViewModels
         public RelayCommand<Channel> ShowExportSetupCommand { get; }
 
         public MainViewModel(ISettingsService settingsService, IUpdateService updateService, IDataService dataService,
-            IMessageGroupService messageGroupService, IExportService exportService)
+            IChatLogService chatLogService, IExportService exportService)
         {
             _settingsService = settingsService;
             _updateService = updateService;
             _dataService = dataService;
-            _messageGroupService = messageGroupService;
+            _chatLogService = chatLogService;
             _exportService = exportService;
 
             _guildChannelsMap = new Dictionary<Guild, IReadOnlyList<Channel>>();
@@ -256,21 +256,11 @@ namespace DiscordChatExporter.Gui.ViewModels
 
             try
             {
-                // TODO: extract this to make it reusable across implementations
-                // Get messages
-                var messages = await _dataService.GetChannelMessagesAsync(token, channel.Id, from, to, progressHandler);
-
-                // Group messages
-                var messageGroups = _messageGroupService.GroupMessages(messages);
-
-                // Get mentionables
-                var mentionables = await _dataService.GetMentionablesAsync(token, guild.Id, messages);
-
-                // Create log
-                var log = new ChatLog(guild, channel, from, to, messageGroups, mentionables);
+                // Get chat log
+                var chatLog = await _chatLogService.GetChatLogAsync(token, guild, channel, from, to, progressHandler);
 
                 // Export
-                _exportService.Export(format, filePath, log);
+                _exportService.Export(format, filePath, chatLog);
 
                 // Open
                 Process.Start(filePath);