fix(tgbot-front): start fixing navigation callback processing function

modules/bot/front/src/handlers.cpp

@@ -85,56 +85,66 @@ void BotHandlers::processCallbackImpl(TgBot::CallbackQuery::Ptr query) {
     }
 }
 
-std::pair<HandlerResult, UserContext> BotHandlers::newStateNavigation(const TgBot::CallbackQuery::Ptr& query, const UserContext& ctx) {
+void BotHandlers::handleNavigation(TgBot::CallbackQuery::Ptr query) {
-    const std::string& data = query->data;
+    int64_t userId = query->from->id;
-    switch (ctx.state) {
+    auto it = userContexts.find(userId);
-        case UserState::MAIN_MENU:
+    if (it == userContexts.end()) {
-            if(data == BotConstants::Callback::MY_TITLES) {
+        // TODO: log
-                UserContext newCtx{.state = UserState::VIEWING_MY_TITLES, .cursor = BotConstants::CURSOR_NOT_INIT};
+        std::cout << "Error: Не нашел пользователя " << userId;
-                HandlerResult result = returnMyTitles(query->from->id);
+        return;
-
-                return {result, newCtx};
-            }
-        case UserState::VIEWING_MY_TITLES:
-            if(data == BotConstants::Callback::LIST_PREV) {
-
-            }
-            else if (data == BotConstants::Callback::LIST_NEXT) {
-
-            }
-        case UserState::AWAITING_TITLE_NAME:
-            if(data == BotConstants::Callback::LIST_PREV) {
-
-            }
-        case UserState::VIEWING_TITLE_PAGE:
-            if(data == BotConstants::Callback::LIST_PREV) {
-
-            }
-        case UserState::AWAITING_REVIEW:
-            if(data == BotConstants::Callback::LIST_PREV) {
-
-            }
-        case UserState::VIEWING_REVIEW_LIST:
-            if(data == BotConstants::Callback::LIST_PREV) {
-
-            }
-            else if (data == BotConstants::Callback::LIST_NEXT) {
-
-            }
-        case UserState::VIEWING_REVIEW:
-            if(data == BotConstants::Callback::LIST_PREV) {
-
-            }
-        case UserState::VIEWING_DESCRIPTION:
-            if(data == BotConstants::Callback::LIST_PREV) {
-
-            }
-        default:
-            UserContext newCtx{.state = UserState::ERROR, .cursor = BotConstants::CURSOR_NOT_INIT};
-            HandlerResult result = {"", nullptr};
-
-            return {result, newCtx};
     }
+
+    UserContext& ctx = it->second;
+    const auto& current = ctx.history.back(); // текущий экран
+    const std::string& data = query->data;
+
+    // Пагинация (в списках)
+    if ((data == BotConstants::Callback::LIST_PREV || data == BotConstants::Callback::LIST_NEXT)
+        && (current.state == UserState::VIEWING_MY_TITLES || current.state == UserState::VIEWING_REVIEW_LIST || 
+            current.state == UserState::VIEWING_FOUND_TITLES)) {
+
+        int64_t newPayload = current.payload;
+        if (data == BotConstants::Callback::LIST_PREV && newPayload > 0) {
+            reducePayload(newPayload, current.state);
+        } else if (data == BotConstants::Callback::LIST_NEXT) {
+            increasePayload(newPayload, current.state);
+        } else {
+            if (data == BotConstants::Callback::LIST_PREV) {
+                std::cout << "Error: navigation:prev callback for 1st page" << std::endl;
+                return;
+            }
+            // TODO: log
+            std::cout << "Error: navigation:prev unknown error" << std::endl;
+        }
+
+        ctx.history.back().payload = newPayload;
+
+        auto result = renderCurrent(ctx);
+        editMessage(query, result);
+        return;
+    }
+
+    // Обработка back по интерфейсу
+    if (data == BotConstants::Callback::NAV_BACK) {
+        if (!popState(ctx)) {
+            botApi.answerCallbackQuery(query->id, "Некуда возвращаться", true);
+            return;
+        }
+        auto result = renderCurrent(ctx);
+        editMessage(query, result);
+        return;
+    }
+
+    // Переходы вперёд (push)
+    auto newStepOpt = computeNextStep(query, current);
+    if (!newStepOpt.has_value()) {
+        sendError(query->message->chat->id);
+        return;
+    }
+
+    ctx.history.push_back(*newStepOpt);
+    auto result = renderCurrent(ctx);
+    editMessage(query, result);
 }
 
 void BotHandlers::pushState(UserContext& ctx, UserState newState, int64_t payload) {
@@ -146,3 +156,29 @@ bool BotHandlers::popState(UserContext& ctx) {
     ctx.history.pop_back();
     return true;
 }
+
+void BotHandlers::reducePayload(int64_t& payload, const UserState curState) {
+    if (curState == UserState::VIEWING_MY_TITLES || 
+        curState == UserState::VIEWING_FOUND_TITLES) {
+        payload -= BotConstants::DISP_TITLES_NUM;
+    } else if (curState == UserState::VIEWING_REVIEW_LIST) {
+        payload -= BotConstants::DISP_REVIEW_NUM;
+    } else {
+        // TODO: log
+        payload = BotConstants::NULL_PAYLOAD;
+        std::cerr << "Error: reducePayload" << std::endl;
+    }
+}
+
+void BotHandlers::increasePayload(int64_t& payload, const UserState curState) {
+    if (curState == UserState::VIEWING_MY_TITLES || 
+        curState == UserState::VIEWING_FOUND_TITLES) {
+        payload += BotConstants::DISP_TITLES_NUM;
+    } else if (curState == UserState::VIEWING_REVIEW_LIST) {
+        payload += BotConstants::DISP_REVIEW_NUM;
+    } else {
+        // TODO: log
+        payload = BotConstants::NULL_PAYLOAD;
+        std::cerr << "Error: increasePayload" << std::endl;
+    }
+}