feat(assistant): add conversations list, infinite history scroll, and archived tab

backend/src/api/routes/__tests__/test_assistant_api.py

@@ -9,6 +9,7 @@
 import os
 import asyncio
 from types import SimpleNamespace
+from datetime import datetime, timedelta
 
 # Force isolated sqlite databases for test module before dependencies import.
 os.environ.setdefault("DATABASE_URL", "sqlite:////tmp/ss_tools_assistant_api.db")
@@ -391,4 +392,144 @@ def test_llm_validation_missing_dashboard_returns_needs_clarification():
 
 
 # [/DEF:test_llm_validation_missing_dashboard_returns_needs_clarification:Function]
+
+
+# [DEF:test_list_conversations_groups_by_conversation_and_marks_archived:Function]
+# @PURPOSE: Conversations endpoint must group messages and compute archived marker by inactivity threshold.
+# @PRE: Fake DB contains two conversations with different update timestamps.
+# @POST: Response includes both conversations with archived flag set for stale one.
+def test_list_conversations_groups_by_conversation_and_marks_archived():
+    _clear_assistant_state()
+    db = _FakeDb()
+    now = datetime.utcnow()
+
+    db.add(
+        AssistantMessageRecord(
+            id="m-1",
+            user_id="u-admin",
+            conversation_id="conv-active",
+            role="user",
+            text="active chat",
+            created_at=now,
+        )
+    )
+    db.add(
+        AssistantMessageRecord(
+            id="m-2",
+            user_id="u-admin",
+            conversation_id="conv-old",
+            role="user",
+            text="old chat",
+            created_at=now - timedelta(days=assistant_module.ASSISTANT_ARCHIVE_AFTER_DAYS + 2),
+        )
+    )
+
+    result = _run_async(
+        assistant_module.list_conversations(
+            page=1,
+            page_size=20,
+            include_archived=True,
+            search=None,
+            current_user=_admin_user(),
+            db=db,
+        )
+    )
+
+    assert result["total"] == 2
+    by_id = {item["conversation_id"]: item for item in result["items"]}
+    assert by_id["conv-active"]["archived"] is False
+    assert by_id["conv-old"]["archived"] is True
+
+
+# [/DEF:test_list_conversations_groups_by_conversation_and_marks_archived:Function]
+
+
+# [DEF:test_history_from_latest_returns_recent_page_first:Function]
+# @PURPOSE: History endpoint from_latest mode must return newest page while preserving chronological order in chunk.
+# @PRE: Conversation has more messages than single page size.
+# @POST: First page returns latest messages and has_next indicates older pages exist.
+def test_history_from_latest_returns_recent_page_first():
+    _clear_assistant_state()
+    db = _FakeDb()
+    base_time = datetime.utcnow() - timedelta(minutes=10)
+    conv_id = "conv-paginated"
+    for i in range(4, -1, -1):
+        db.add(
+            AssistantMessageRecord(
+                id=f"msg-{i}",
+                user_id="u-admin",
+                conversation_id=conv_id,
+                role="user" if i % 2 == 0 else "assistant",
+                text=f"message-{i}",
+                created_at=base_time + timedelta(minutes=i),
+            )
+        )
+
+    result = _run_async(
+        assistant_module.get_history(
+            page=1,
+            page_size=2,
+            conversation_id=conv_id,
+            from_latest=True,
+            current_user=_admin_user(),
+            db=db,
+        )
+    )
+
+    assert result["from_latest"] is True
+    assert result["has_next"] is True
+    # Chunk is chronological while representing latest page.
+    assert [item["text"] for item in result["items"]] == ["message-3", "message-4"]
+
+
+# [/DEF:test_history_from_latest_returns_recent_page_first:Function]
+
+
+# [DEF:test_list_conversations_archived_only_filters_active:Function]
+# @PURPOSE: archived_only mode must return only archived conversations.
+# @PRE: Dataset includes one active and one archived conversation.
+# @POST: Only archived conversation remains in response payload.
+def test_list_conversations_archived_only_filters_active():
+    _clear_assistant_state()
+    db = _FakeDb()
+    now = datetime.utcnow()
+    db.add(
+        AssistantMessageRecord(
+            id="m-active",
+            user_id="u-admin",
+            conversation_id="conv-active-2",
+            role="user",
+            text="active",
+            created_at=now,
+        )
+    )
+    db.add(
+        AssistantMessageRecord(
+            id="m-archived",
+            user_id="u-admin",
+            conversation_id="conv-archived-2",
+            role="user",
+            text="archived",
+            created_at=now - timedelta(days=assistant_module.ASSISTANT_ARCHIVE_AFTER_DAYS + 3),
+        )
+    )
+
+    result = _run_async(
+        assistant_module.list_conversations(
+            page=1,
+            page_size=20,
+            include_archived=True,
+            archived_only=True,
+            search=None,
+            current_user=_admin_user(),
+            db=db,
+        )
+    )
+
+    assert result["total"] == 1
+    assert result["items"][0]["conversation_id"] == "conv-archived-2"
+    assert result["items"][0]["archived"] is True
+
+
+# [/DEF:test_list_conversations_archived_only_filters_active:Function]
 # [/DEF:backend.src.api.routes.__tests__.test_assistant_api:Module]