fix: allow chat history persistence throughout user session (#92)

* Initial plan

* Implement chat history persistence across user sessions and workspaces

Co-authored-by: vedantthapa <43611693+vedantthapa@users.noreply.github.com>

* Fix chat history persistence to use workspace and user scoped cache

Co-authored-by: vedantthapa <43611693+vedantthapa@users.noreply.github.com>

* Address code review feedback - add nil checks and fix callback handling

Co-authored-by: vedantthapa <43611693+vedantthapa@users.noreply.github.com>

* Cache only messages instead of entire LLMChain struct

Co-authored-by: vedantthapa <43611693+vedantthapa@users.noreply.github.com>

* Refactor: Use pattern matching instead of if conditions for cache operations

Co-authored-by: vedantthapa <43611693+vedantthapa@users.noreply.github.com>

* refactor: use original code patterns to reduce diff

* refactor: rm helper function

* fix: rm extra Map.put since it's not required

* fix: fmt file

* chore: rm tool-versions

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>

Author: vedantthapa

valentine/lib/valentine_web/components/layouts/app.html.heex

@@ -118,6 +118,7 @@
               active_module={@active_module}
               active_action={@active_action}
               workspace_id={@workspace_id || nil}
+              current_user={@current_user}
             />
           </div>
         </div>

valentine/lib/valentine_web/live/workspace_live/components/chat_component.ex

@@ -91,7 +91,11 @@ defmodule ValentineWeb.WorkspaceLive.Components.ChatComponent do
       socket.assigns.chain
       |> LLMChain.apply_delta(data)
 
-    Valentine.Cache.put({socket.id, :chatbot_history}, chain, expire: :timer.hours(24))
+    %{workspace_id: workspace_id, current_user: user_id} = socket.assigns
+
+    Valentine.Cache.put({workspace_id, user_id, :chatbot_history}, chain.messages,
+      expire: :timer.hours(24)
+    )
 
     {:ok,
      socket
@@ -119,7 +123,8 @@ defmodule ValentineWeb.WorkspaceLive.Components.ChatComponent do
   end
 
   def update(assigns, socket) do
-    cached_chain = Valentine.Cache.get({socket.id, :chatbot_history}) || %LLMChain{}
+    %{workspace_id: workspace_id, current_user: user_id} = assigns
+    cached_messages = Valentine.Cache.get({workspace_id, user_id, :chatbot_history}) || []
 
     {:ok,
      socket
@@ -137,7 +142,7 @@ defmodule ValentineWeb.WorkspaceLive.Components.ChatComponent do
          callbacks: [llm_handler(self(), socket.assigns.myself)],
          cid: socket.assigns.myself
        })
-       |> LLMChain.add_messages(cached_chain.messages)
+       |> LLMChain.add_messages(cached_messages)
      )
      |> assign(assigns)}
   end
@@ -155,6 +160,8 @@ defmodule ValentineWeb.WorkspaceLive.Components.ChatComponent do
   end
 
   def handle_event("chat_submit", %{"value" => "/clear"}, socket) do
+    %{workspace_id: workspace_id, current_user: user_id} = socket.assigns
+
     chain =
       build_chain(%{
         stream: true,
@@ -169,16 +176,21 @@ defmodule ValentineWeb.WorkspaceLive.Components.ChatComponent do
         cid: socket.assigns.myself
       })
 
-    Valentine.Cache.put({socket.id, :chatbot_history}, chain, expire: :timer.hours(24))
+    # Clear from cache (store empty messages list)
+    Valentine.Cache.put({workspace_id, user_id, :chatbot_history}, [], expire: :timer.hours(24))
 
     {:noreply,
      socket
      |> assign(chain: chain)}
   end
 
   def handle_event("chat_submit", %{"value" => value}, socket) do
-    %{active_module: active_module, active_action: active_action, workspace_id: workspace_id} =
-      socket.assigns
+    %{
+      workspace_id: workspace_id,
+      current_user: user_id,
+      active_module: active_module,
+      active_action: active_action
+    } = socket.assigns
 
     chain =
       socket.assigns.chain
@@ -189,7 +201,9 @@ defmodule ValentineWeb.WorkspaceLive.Components.ChatComponent do
         Message.new_user!(value)
       ])
 
-    Valentine.Cache.put({socket.id, :chatbot_history}, chain, expire: :timer.hours(24))
+    Valentine.Cache.put({workspace_id, user_id, :chatbot_history}, chain.messages,
+      expire: :timer.hours(24)
+    )
 
     {:noreply,
      socket

valentine/test/valentine_web/live/components/chat_component_test.exs

@@ -17,7 +17,8 @@ defmodule ValentineWeb.WorkspaceLive.Components.ChatComponentTest do
       chain: %LangChain.Chains.LLMChain{},
       id: "chat-component",
       skills: [],
-      workspace_id: workspace.id
+      workspace_id: workspace.id,
+      current_user: "test_user@example.com"
     }
 
     socket = %Phoenix.LiveView.Socket{
@@ -158,6 +159,8 @@ defmodule ValentineWeb.WorkspaceLive.Components.ChatComponentTest do
       assigns = %{
         active_module: "some_active_module",
         active_action: "some_active_action",
+        workspace_id: socket.assigns.workspace_id,
+        current_user: socket.assigns.current_user,
         some_key: "some_value"
       }