feat(rates): record hourly rate history

apps/workspaces/services/rates.py

@@ -1,6 +1,34 @@
 from django.utils import timezone
 
-from apps.workspaces.models import WorkspaceUserRate
+from apps.workspaces.models import HourlyRateHistory, WorkspaceUserRate
+
+
+def record_workspace_rate_history(*, workspace, user_id, hourly_rate, currency, effective_from=None):
+    currency = currency.upper()
+    effective_from = effective_from or timezone.now()
+    latest = (
+        HourlyRateHistory.objects.filter(
+            workspace=workspace,
+            user_id=user_id,
+            scope=HourlyRateHistory.Scope.WORKSPACE,
+            project__isnull=True,
+            is_deleted=False,
+        )
+        .order_by("-effective_from", "-created_at")
+        .first()
+    )
+    if latest and latest.hourly_rate == hourly_rate and latest.currency == currency:
+        return latest
+    return HourlyRateHistory.objects.create(
+        workspace=workspace,
+        user_id=user_id,
+        project=None,
+        scope=HourlyRateHistory.Scope.WORKSPACE,
+        hourly_rate=hourly_rate,
+        currency=currency,
+        effective_from=effective_from,
+        is_active=True,
+    )
 
 
 def upsert_workspace_user_rate(workspace, user_id, hourly_rate, currency="USD"):
@@ -11,6 +39,7 @@ def upsert_workspace_user_rate(workspace, user_id, hourly_rate, currency="USD"):
         is_deleted=False,
     ).first()
 
+    effective_from = timezone.now()
     if rate:
         update_fields = []
         if rate.hourly_rate != hourly_rate:
@@ -25,16 +54,31 @@ def upsert_workspace_user_rate(workspace, user_id, hourly_rate, currency="USD"):
         if update_fields:
             update_fields.append("updated_at")
             rate.save(update_fields=update_fields)
+            record_workspace_rate_history(
+                workspace=workspace,
+                user_id=user_id,
+                hourly_rate=rate.hourly_rate,
+                currency=rate.currency,
+                effective_from=effective_from,
+            )
         return rate
 
-    return WorkspaceUserRate.objects.create(
+    rate = WorkspaceUserRate.objects.create(
         workspace=workspace,
         user_id=user_id,
         hourly_rate=hourly_rate,
         currency=currency,
-        effective_from=timezone.now(),
+        effective_from=effective_from,
         is_active=True,
     )
+    record_workspace_rate_history(
+        workspace=workspace,
+        user_id=user_id,
+        hourly_rate=rate.hourly_rate,
+        currency=rate.currency,
+        effective_from=rate.effective_from,
+    )
+    return rate
 
 
 def update_workspace_user_rate(rate_instance, **kwargs):
@@ -50,5 +94,12 @@ def update_workspace_user_rate(rate_instance, **kwargs):
     if update_fields:
         update_fields.append("updated_at")
         rate_instance.save(update_fields=update_fields)
+        if {"hourly_rate", "currency", "is_active"} & set(update_fields):
+            record_workspace_rate_history(
+                workspace=rate_instance.workspace,
+                user_id=rate_instance.user_id,
+                hourly_rate=rate_instance.hourly_rate,
+                currency=rate_instance.currency,
+            )
 
     return rate_instance