fix - Integrate CLS session persistence and restoration for conversation history

com.microsoft.copilot.eclipse.core/src/com/microsoft/copilot/eclipse/core/Constants.java

@@ -28,6 +28,7 @@ private Constants() {
   public static final String WORKSPACE_CONTEXT_ENABLED = "workspaceContextEnabled";
   public static final String SUB_AGENT_ENABLED = "subAgentEnabled";
   public static final String AGENT_MAX_REQUESTS = "agentMaxRequests";
+  public static final String TRANSCRIPT_SUBDIR = ".copilot/eclipse";
   public static final String MCP = "mcp";
   public static final String MCP_REGISTRY_URL = "mcpRegistryUrl";
   public static final String MCP_REGISTRY_VERSION = "v0.1";

com.microsoft.copilot.eclipse.core/src/com/microsoft/copilot/eclipse/core/lsp/CopilotLanguageServerConnection.java

@@ -278,6 +278,18 @@ public CompletableFuture<ChatCreateResult> createConversation(String workDoneTok
       List<IResource> files, IFile currentFile, Range currentSelection, List<Turn> turns, CopilotModel activeModel,
       String chatModeName, String customChatModeId, List<TodoItem> todos, String agentSlug,
       String agentJobWorkspaceFolder) {
+    return createConversation(workDoneToken, message, files, currentFile, currentSelection, turns, activeModel,
+        chatModeName, customChatModeId, todos, agentSlug, agentJobWorkspaceFolder, null, null);
+  }
+
+  /**
+   * Create a conversation with the given parameters, including optional conversationId and restoreToTurnId for session
+   * restoration.
+   */
+  public CompletableFuture<ChatCreateResult> createConversation(String workDoneToken, String message,
+      List<IResource> files, IFile currentFile, Range currentSelection, List<Turn> turns, CopilotModel activeModel,
+      String chatModeName, String customChatModeId, List<TodoItem> todos, String agentSlug,
+      String agentJobWorkspaceFolder, String conversationId, String restoreToTurnId) {
     boolean supportVision = activeModel.getCapabilities().supports().vision();
     Either<String, List<ChatCompletionContentPart>> messageWithImages = ChatMessageUtils
         .createMessageWithImages(message, FileUtils.filterFilesFrom(files), supportVision);
@@ -308,6 +320,13 @@ public CompletableFuture<ChatCreateResult> createConversation(String workDoneTok
 
       // TODO: remove needToolCallConfirmation when CLS fully supports it across all IDEs.
       param.setNeedToolCallConfirmation(true);
+
+      // Set conversationId and restoreToTurnId for session restoration from history
+      if (conversationId != null) {
+        param.setConversationId(conversationId);
+        param.setRestoreToTurnId(restoreToTurnId);
+      }
+
       if (currentFile != null) {
         param.setTextDocument(new TextDocumentIdentifier(FileUtils.getResourceUri(currentFile)));
         if (currentSelection != null) {

com.microsoft.copilot.eclipse.core/src/com/microsoft/copilot/eclipse/core/lsp/protocol/ConversationCreateParams.java

@@ -39,6 +39,8 @@ public class ConversationCreateParams {
   // TODO: remove needToolCallConfirmation when CLS fully supports it across all IDEs.
   private boolean needToolCallConfirmation;
   private List<TodoItem> todoList;
+  private String conversationId;
+  private String restoreToTurnId;
 
   /**
    * Creates a new ConversationCreateParams.
@@ -198,6 +200,22 @@ public void setModelProviderName(String modelProviderName) {
     this.modelProviderName = modelProviderName;
   }
 
+  public String getConversationId() {
+    return conversationId;
+  }
+
+  public void setConversationId(String conversationId) {
+    this.conversationId = conversationId;
+  }
+
+  public String getRestoreToTurnId() {
+    return restoreToTurnId;
+  }
+
+  public void setRestoreToTurnId(String restoreToTurnId) {
+    this.restoreToTurnId = restoreToTurnId;
+  }
+
   @Override
   public int hashCode() {
     final int prime = 31;
@@ -207,7 +225,7 @@ public int hashCode() {
     result = prime * result
         + Objects.hash(capabilities, chatMode, computeSuggestions, customChatModeId, model, needToolCallConfirmation,
             references, source, textDocument, userLanguage, workDoneToken, workspaceFolder, workspaceFolders,
-            modelProviderName, todoList);
+            modelProviderName, todoList, conversationId, restoreToTurnId);
     return result;
   }
 
@@ -233,7 +251,9 @@ public boolean equals(Object obj) {
         && Objects.equals(workDoneToken, other.workDoneToken) && Objects.equals(workspaceFolder, other.workspaceFolder)
         && Objects.equals(workspaceFolders, other.workspaceFolders)
         && Objects.equals(modelProviderName, other.modelProviderName)
-        && Objects.equals(todoList, other.todoList);
+        && Objects.equals(todoList, other.todoList)
+        && Objects.equals(conversationId, other.conversationId)
+        && Objects.equals(restoreToTurnId, other.restoreToTurnId);
   }
 
   @Override
@@ -256,6 +276,8 @@ public String toString() {
     builder.append("customChatModeId", customChatModeId);
     builder.append("needToolCallConfirmation", needToolCallConfirmation);
     builder.append("todoList", todoList);
+    builder.append("conversationId", conversationId);
+    builder.append("restoreToTurnId", restoreToTurnId);
     return builder.toString();
   }
 }

com.microsoft.copilot.eclipse.core/src/com/microsoft/copilot/eclipse/core/lsp/protocol/CopilotAgentSettings.java

@@ -16,6 +16,8 @@ public class CopilotAgentSettings {
   @SerializedName("maxToolCallingLoop")
   private int agentMaxRequests;
 
+  private String transcriptDirectory;
+
   public int getAgentMaxRequests() {
     return agentMaxRequests;
   }
@@ -24,9 +26,17 @@ public void setAgentMaxRequests(int agentMaxRequests) {
     this.agentMaxRequests = agentMaxRequests;
   }
 
+  public String getTranscriptDirectory() {
+    return transcriptDirectory;
+  }
+
+  public void setTranscriptDirectory(String transcriptDirectory) {
+    this.transcriptDirectory = transcriptDirectory;
+  }
+
   @Override
   public int hashCode() {
-    return Objects.hash(agentMaxRequests);
+    return Objects.hash(agentMaxRequests, transcriptDirectory);
   }
 
   @Override
@@ -38,13 +48,15 @@ public boolean equals(Object obj) {
       return false;
     }
     CopilotAgentSettings other = (CopilotAgentSettings) obj;
-    return agentMaxRequests == other.agentMaxRequests;
+    return agentMaxRequests == other.agentMaxRequests
+        && Objects.equals(transcriptDirectory, other.transcriptDirectory);
   }
 
   @Override
   public String toString() {
     ToStringBuilder builder = new ToStringBuilder(this);
     builder.append("agentMaxRequests", agentMaxRequests);
+    builder.append("transcriptDirectory", transcriptDirectory);
     return builder.toString();
   }
 }

com.microsoft.copilot.eclipse.core/src/com/microsoft/copilot/eclipse/core/lsp/protocol/Turn.java

@@ -18,6 +18,7 @@ public class Turn {
   Either<String, List<ChatCompletionContentPart>> request;
   String response;
   String agentSlug;
+  String turnId;
 
   /**
    * Creates a new Turn.
@@ -28,6 +29,17 @@ public Turn(@NonNull Either<String, List<ChatCompletionContentPart>> request, St
     this.agentSlug = agentSlug;
   }
 
+  /**
+   * Creates a new Turn with turnId.
+   */
+  public Turn(@NonNull Either<String, List<ChatCompletionContentPart>> request, String response, String agentSlug,
+      String turnId) {
+    this.request = request;
+    this.response = response;
+    this.agentSlug = agentSlug;
+    this.turnId = turnId;
+  }
+
   public Either<String, List<ChatCompletionContentPart>> getRequest() {
     return request;
   }
@@ -52,9 +64,17 @@ public void setAgentSlug(String agentSlug) {
     this.agentSlug = agentSlug;
   }
 
+  public String getTurnId() {
+    return turnId;
+  }
+
+  public void setTurnId(String turnId) {
+    this.turnId = turnId;
+  }
+
   @Override
   public int hashCode() {
-    return Objects.hash(request, response, agentSlug);
+    return Objects.hash(request, response, agentSlug, turnId);
   }
 
   @Override
@@ -67,7 +87,7 @@ public boolean equals(Object o) {
     }
     Turn turn = (Turn) o;
     return Objects.equals(request, turn.request) && Objects.equals(response, turn.response)
-        && Objects.equals(agentSlug, turn.agentSlug);
+        && Objects.equals(agentSlug, turn.agentSlug) && Objects.equals(turnId, turn.turnId);
   }
 
   @Override
@@ -76,6 +96,7 @@ public String toString() {
     builder.append("request", request);
     builder.append("response", response);
     builder.append("agentSlug", agentSlug);
+    builder.append("turnId", turnId);
     return builder.toString();
   }
 }

com.microsoft.copilot.eclipse.core/src/com/microsoft/copilot/eclipse/core/persistence/ConversationDataFactory.java

@@ -27,7 +27,6 @@
 import com.microsoft.copilot.eclipse.core.persistence.CopilotTurnData.ToolCallData;
 import com.microsoft.copilot.eclipse.core.persistence.UserTurnData.MessageData;
 
-
 /**
  * Factory for creating and transforming conversation data objects. Responsible only for pure data transformation with
  * no business logic.
@@ -208,6 +207,8 @@ public List<Turn> convertToTurns(List<AbstractTurnData> turnDataList) {
     // Defensive copy to avoid ConcurrentModificationException if another thread mutates the list while iterating.
     List<AbstractTurnData> snapshot = new ArrayList<>(turnDataList);
     List<Turn> result = new ArrayList<>(snapshot.size());
+    Turn unpairedUserTurn = null;
+
     for (AbstractTurnData turnData : snapshot) {
       if (turnData == null) {
         continue;
@@ -218,17 +219,31 @@ public List<Turn> convertToTurns(List<AbstractTurnData> turnDataList) {
         continue;
       }
       if (turnData instanceof UserTurnData userTurnData) {
+        // Flush any unpaired user turn without a response
+        if (unpairedUserTurn != null) {
+          result.add(unpairedUserTurn);
+        }
         String requestText = userTurnData.getMessage() != null ? userTurnData.getMessage().getText() : "";
         Either<String, List<ChatCompletionContentPart>> request = Either
             .forLeft(requestText == null ? "" : requestText);
-        result.add(new Turn(request, null, null));
+        unpairedUserTurn = new Turn(request, null, null, turnData.getTurnId());
       } else if (turnData instanceof CopilotTurnData copilotTurnData) {
-        // Assistant turns only contribute the response text; the request field is intentionally empty.
         String responseText = extractResponseFromCopilotTurnData(copilotTurnData);
-        Either<String, List<ChatCompletionContentPart>> request = Either.forLeft("");
-        result.add(new Turn(request, responseText, null));
+        if (unpairedUserTurn != null) {
+          // Pair the response with the unpaired user turn
+          unpairedUserTurn.setResponse(responseText);
+          result.add(unpairedUserTurn);
+          unpairedUserTurn = null;
+        } else {
+          // Orphaned copilot turn (no preceding user turn), create a standalone turn
+          result.add(new Turn(Either.forLeft(""), responseText, null, turnData.getTurnId()));
+        }
       }
     }
+    // Flush any remaining unpaired user turn (user message without a response)
+    if (unpairedUserTurn != null) {
+      result.add(unpairedUserTurn);
+    }
     return result;
   }
 

com.microsoft.copilot.eclipse.core/src/com/microsoft/copilot/eclipse/core/persistence/ConversationPersistenceManager.java

@@ -299,47 +299,42 @@ private ConversationData updateConversationProgressInternal(String conversationI
     return conversationData;
   }
 
-  private UserTurnData findOrCreateUserTurn(ConversationData conversation, String turnId) {
-    if (turnId != null) {
-      AbstractTurnData existingTurn = findTurn(conversation, turnId);
-      if (existingTurn != null && existingTurn instanceof UserTurnData userTurnData) {
-        return userTurnData;
+  /**
+   * Finds a turn by ID and type in the conversation.
+   */
+  @SuppressWarnings("unchecked")
+  private <T extends AbstractTurnData> T findTurn(ConversationData conversation, String turnId, Class<T> type) {
+    if (turnId == null) {
+      return null;
+    }
+    for (AbstractTurnData t : conversation.getTurns()) {
+      if (turnId.equals(t.getTurnId()) && type.isInstance(t)) {
+        return (T) t;
       }
     }
+    return null;
+  }
 
+  private UserTurnData findOrCreateUserTurn(ConversationData conversation, String turnId) {
+    UserTurnData existing = findTurn(conversation, turnId, UserTurnData.class);
+    if (existing != null) {
+      return existing;
+    }
     UserTurnData turn = dataFactory.createUserTurnData(conversation.getConversationId(), turnId, "", null, null, null);
     conversation.getTurns().add(turn);
     return turn;
   }
 
   private CopilotTurnData findOrCreateCopilotTurn(ConversationData conversation, String turnId) {
-    if (turnId != null) {
-      AbstractTurnData existingTurn = findTurn(conversation, turnId);
-      if (existingTurn != null && existingTurn instanceof CopilotTurnData copilotTurnData) {
-        return copilotTurnData;
-      }
+    CopilotTurnData existing = findTurn(conversation, turnId, CopilotTurnData.class);
+    if (existing != null) {
+      return existing;
     }
-
     CopilotTurnData turn = dataFactory.createCopilotTurnData(turnId);
     conversation.getTurns().add(turn);
     return turn;
   }
 
-  /**
-   * Finds a turn by ID in the conversation.
-   */
-  private AbstractTurnData findTurn(ConversationData conversation, String turnId) {
-    if (conversation == null || turnId == null) {
-      return null;
-    }
-    for (AbstractTurnData t : conversation.getTurns()) {
-      if (turnId.equals(t.getTurnId())) {
-        return t;
-      }
-    }
-    return null;
-  }
-
   private ConversationData getOrCreateNewConversationById(String conversationId) throws IOException {
     try {
       ConversationData existedConversation = getConversationFromCacheOrLoadFromDisk(conversationId);
@@ -549,6 +544,42 @@ public ConversationDataFactory getDataFactory() {
     return dataFactory;
   }
 
+  /**
+   * Sets the CLS-assigned turnId on the last user turn that doesn't have a turnId yet. User turns are initially
+   * persisted without a turnId (null), and the server-assigned turnId is set when the CLS progress begin event arrives.
+   *
+   * @param conversationId the conversation ID
+   * @param turnId the server-assigned turnId from CLS
+   */
+  public void setUserTurnId(String conversationId, String turnId) {
+    if (turnId == null) {
+      return;
+    }
+    CompletableFuture.runAsync(() -> {
+      lock.writeLock().lock();
+      try {
+        ConversationData conversation = getConversationFromCacheOrLoadFromDisk(conversationId);
+        if (conversation == null) {
+          return;
+        }
+        // Find the last UserTurnData with null turnId and set it
+        List<AbstractTurnData> turns = conversation.getTurns();
+        for (int i = turns.size() - 1; i >= 0; i--) {
+          AbstractTurnData t = turns.get(i);
+          if (t instanceof UserTurnData && t.getTurnId() == null) {
+            t.setTurnId(turnId);
+            persistAndCacheConversation(conversation);
+            break;
+          }
+        }
+      } catch (IOException e) {
+        CopilotCore.LOGGER.error("Failed to set user turn ID for conversation: " + conversationId, e);
+      } finally {
+        lock.writeLock().unlock();
+      }
+    });
+  }
+
   /**
    * Sets the subagentToolCallId on a subagent's CopilotTurnData to associate it with the parent turn's run_subagent
    * tool call. This enables precise positioning of subagent content during conversation restoration.
@@ -570,9 +601,9 @@ public CompletableFuture<Void> setSubagentToolCallId(String conversationId, Stri
         if (conversation == null) {
           return;
         }
-        AbstractTurnData turnData = findTurn(conversation, subagentTurnId);
-        if (turnData instanceof CopilotTurnData turn && turn.getSubagentToolCallId() == null) {
-          turn.setSubagentToolCallId(toolCallId);
+        CopilotTurnData turnData = findTurn(conversation, subagentTurnId, CopilotTurnData.class);
+        if (turnData != null && turnData.getSubagentToolCallId() == null) {
+          turnData.setSubagentToolCallId(toolCallId);
         }
       } catch (IOException e) {
         CopilotCore.LOGGER.error("Failed to set subagent tool call ID: " + conversationId, e);