Randomly choose next text

src/FillInTheTextBot.Messengers.Yandex/YandexService.cs

@@ -1,8 +1,10 @@
 using System;
 using System.Collections.Generic;
 using System.Diagnostics;
+using System.Linq;
 using System.Threading.Tasks;
 using FillInTheTextBot.Services;
+using FillInTheTextBot.Services.Extensions;
 using Microsoft.Extensions.Logging;
 using Yandex.Dialogs.Models;
 using Yandex.Dialogs.Models.Input;
@@ -30,26 +32,22 @@ protected override Models.Request Before(InputModel input)
             var request = input.ToRequest();
 
             input.TryGetFromUserState(Models.Request.IsOldUserKey, out bool isOldUser);
-
             request.IsOldUser = isOldUser;
 
-            if (input.TryGetFromUserState(Models.Response.NextTextIndexStorageKey, out object nextTextIndex) != true)
-            {
-                input.TryGetFromApplicationState(Models.Response.NextTextIndexStorageKey, out nextTextIndex);
-            }
-
-            request.NextTextIndex = Convert.ToInt32(nextTextIndex);
-
             input.TryGetFromSessionState(Models.Response.ScopeStorageKey, out string scopeKey);
-
             request.ScopeKey = scopeKey;
 
-            if (request.NewSession == true)
-            {
-                var contexts = GetContexts(input);
+            input.TryGetFromSessionState(Models.Response.CurrentTextKey, out string currentText);
+            request.CurrentText = currentText;
 
-                request.RequiredContexts.AddRange(contexts);
-            }
+            input.TryGetFromUserState(Models.Response.PassedTextsKey, out object passedTexts);
+            request.PassedTexts = passedTexts.ToString().Deserialize<string[]>()
+                .Where(s => !string.IsNullOrEmpty(s)).ToList();
+
+            if (request.NewSession != true) return request;
+
+            var contexts = GetContexts(input);
+            request.RequiredContexts.AddRange(contexts);
 
             return request;
         }
@@ -74,8 +72,9 @@ protected override Task<OutputModel> AfterAsync(InputModel input, Models.Respons
 
             output.AddToUserState(Models.Request.IsOldUserKey, true);
 
-            output.AddToUserState(Models.Response.NextTextIndexStorageKey, response.NextTextIndex);
-            output.AddToApplicationState(Models.Response.NextTextIndexStorageKey, response.NextTextIndex);
+            output.AddToSessionState(Models.Response.CurrentTextKey, response.CurrentText);
+
+            output.AddToUserState(Models.Response.PassedTextsKey, response.PassedTexts);
 
             output.AddToSessionState(Models.Response.ScopeStorageKey, response.ScopeKey);
 

src/FillInTheTextBot.Models/Request.cs

@@ -35,6 +35,10 @@ public Request()
 
         public int NextTextIndex { get; set; }
 
+        public string CurrentText { get; set; }
+
+        public ICollection<string> PassedTexts { get; set; }
+
         public string ScopeKey { get; set; }
 
         public Appeal Appeal { get; set; }

src/FillInTheTextBot.Models/Response.cs

@@ -6,6 +6,8 @@ public class Response
     {
         public static string NextTextIndexStorageKey => nameof(NextTextIndex).ToUpper();
         public static string ScopeStorageKey => nameof(ScopeKey).ToUpper();
+        public static string PassedTextsKey => nameof(PassedTexts).ToUpper();
+        public static string CurrentTextKey => nameof(CurrentText).ToUpper();
 
         public Response()
         {
@@ -26,8 +28,12 @@ public Response()
 
         public int NextTextIndex { get; set; }
 
+        public string CurrentText { get; set; }
+
+        public IList<string> PassedTexts { get; set; }
+
         public string ScopeKey { get; set; }
-        
+
         public IDictionary<string, string> Emotions { get; set; }
     }
 }

src/FillInTheTextBot.Models/TextsOverException.cs

@@ -0,0 +1,9 @@
+using System;
+
+namespace FillInTheTextBot.Models
+{
+    public class TextsOverException : Exception
+    {
+
+    }
+}

src/FillInTheTextBot.Services/ConversationService.cs

@@ -15,11 +15,13 @@ public class ConversationService : IConversationService
 
         private readonly IDialogflowService _dialogflowService;
         private readonly IRedisCacheService _cache;
+        private readonly Random _random;
 
         public ConversationService(IDialogflowService dialogflowService, IRedisCacheService cache)
         {
             _dialogflowService = dialogflowService;
             _cache = cache;
+            _random = Random.Shared;
         }
 
         public async Task<Response> GetResponseAsync(Request request)
@@ -31,8 +33,9 @@ public async Task<Response> GetResponseAsync(Request request)
                 Text = dialog?.Response,
                 Finished = dialog?.EndConversation ?? false,
                 Buttons = dialog?.Buttons,
-                ScopeKey = dialog?.ScopeKey
-
+                ScopeKey = dialog?.ScopeKey,
+                CurrentText = request.CurrentText,
+                PassedTexts = request.PassedTexts.ToList()
             };
 
             var resetTextIndex = string.Empty;
@@ -41,7 +44,7 @@ public async Task<Response> GetResponseAsync(Request request)
 
             if (isGotResetParameter && string.Equals(resetTextIndex, bool.TrueString, StringComparison.InvariantCultureIgnoreCase))
             {
-                request.NextTextIndex = 0;
+                request.PassedTexts.Clear();
             }
 
             if (string.Equals(dialog?.Action, "GetText"))
@@ -58,16 +61,14 @@ public async Task<Response> GetResponseAsync(Request request)
 
             response.Emotions = GetEmotions(dialog);
 
-            response.NextTextIndex = request.NextTextIndex;
-
             response.Text = GetResponseText(request.Appeal, response.Text);
             response.Buttons = GetButtonsFromPayload(response.Buttons, dialog?.Payload, request.Source);
 
             var texts = TryAddReplacementsFromPayload(dialog?.Payload, request.Source, response.Text);
             response.Text = texts.Text;
             response.AlternativeText = texts.AlternativeText;
 
-            TrySetSavedText(request.SessionId, dialog, texts);
+            TrySetSavedText(request.SessionId, dialog, texts, response);
 
             return response;
         }
@@ -109,7 +110,10 @@ private async Task<Response> GetText(Request request, string startText, string t
         {
             using (Tracing.Trace())
             {
-                var response = new Response();
+                var response = new Response
+                {
+                    PassedTexts = request.PassedTexts.ToList()
+                };
 
                 if (string.IsNullOrEmpty(textKey))
                 {
@@ -124,7 +128,21 @@ private async Task<Response> GetText(Request request, string startText, string t
                             return response;
                         }
 
-                        textKey = GetTextKey(request, texts);
+                        try
+                        {
+                            textKey = GetTextKey(request.PassedTexts, texts);
+
+                            response.CurrentText = textKey;
+                        }
+                        catch (TextsOverException e)
+                        {
+                            if (!string.IsNullOrEmpty(request.CurrentText))
+                            {
+                                textKey = "texts-over";
+                            }
+
+                            response.PassedTexts.Clear();
+                        }
                     }
                 }
 
@@ -146,21 +164,24 @@ private async Task<Response> GetText(Request request, string startText, string t
             }
         }
 
-        private string GetTextKey(Request request, string[] texts)
+        private string GetTextKey(ICollection<string> passedTexts, string[] texts)
         {
-            string textKey;
-
-            var index = request.NextTextIndex++;
-
-            if (index >= texts.Length)
+            if (passedTexts.Count >= texts.Length)
             {
-                textKey = "texts-over";
+                throw new TextsOverException();
             }
-            else
+
+            if (passedTexts.Count == 0)
             {
-                textKey = texts[index];
+                return texts.FirstOrDefault();
             }
 
+            var candidateTexts = texts.Except(passedTexts).ToList();
+
+            var candidateIndex = _random.Next(candidateTexts.Count);
+
+            var textKey = candidateTexts[candidateIndex];
+
             return textKey;
         }
 
@@ -272,7 +293,7 @@ private ICollection<Button> GetButtonsFromPayload(ICollection<Button> responseBu
             }
         }
 
-        private void TrySetSavedText(string sessionId, Dialog dialog, Texts texts)
+        private void TrySetSavedText(string sessionId, Dialog dialog, Texts texts, Response response)
         {
             if (dialog?.ParametersIncomplete != true && string.Equals(dialog?.Action ?? string.Empty, "saveToRepeat", StringComparison.InvariantCultureIgnoreCase))
             {
@@ -283,6 +304,8 @@ private void TrySetSavedText(string sessionId, Dialog dialog, Texts texts)
                 };
 
                 _dialogflowService.SetContextAsync(sessionId, "savedText", 5, parameters).Forget();
+
+                response.PassedTexts.Add(response.CurrentText);
             }
         }
     }

src/FillInTheTextBot.Services/DialogflowService.cs

@@ -52,7 +52,7 @@ public DialogflowService(
                 {InternalModels.Source.Marusia, DefaultWelcomeEventResolve}
             };
         }
-
+        //TODO: remove requiredContext
         public async Task<InternalModels.Dialog> GetResponseAsync(string text, string sessionId, string requiredContext = null)
         {
             var request = new InternalModels.Request