From ee918c2eda3e0570a3fb882a62c40fec83f16f32 Mon Sep 17 00:00:00 2001
From: Graham McIntire <graham@mcintire.me>
Date: Fri, 6 Mar 2026 13:52:28 -0600
Subject: [PATCH] feat: add best-effort subscription migration to new price

---
 lib/towerops/billing.ex        | 43 +++++++++++++++
 test/towerops/billing_test.exs | 95 ++++++++++++++++++++++++++++++++++
 2 files changed, 138 insertions(+)

diff --git a/lib/towerops/billing.ex b/lib/towerops/billing.ex
index 1b181cad..9aeff595 100644
--- a/lib/towerops/billing.ex
+++ b/lib/towerops/billing.ex
@@ -227,6 +227,49 @@ defmodule Towerops.Billing do
     end
   end
 
+  @doc """
+  Migrate all active subscriptions to new price.
+
+  Best-effort migration: continues on individual failures, returns detailed report.
+
+  Returns map with:
+  - total: number of subscriptions attempted
+  - succeeded: number successfully migrated
+  - failed: number of failures
+  - failures: list of {:error, org, reason} tuples
+  """
+  def migrate_all_subscriptions_to_price(new_price_id) do
+    import Ecto.Query
+
+    orgs =
+      Repo.all(
+        from o in Organization,
+          where: o.subscription_status == "active" and not is_nil(o.stripe_subscription_id)
+      )
+
+    results =
+      Enum.map(orgs, fn org ->
+        case StripeClient.update_subscription_price(org.stripe_subscription_id, new_price_id) do
+          {:ok, _} ->
+            {:ok, org}
+
+          {:error, reason} ->
+            Logger.warning("Failed to migrate subscription for org #{org.id}: #{inspect(reason)}")
+            {:error, org, reason}
+        end
+      end)
+
+    successes = Enum.count(results, &match?({:ok, _}, &1))
+    failures = Enum.filter(results, &match?({:error, _, _}, &1))
+
+    %{
+      total: length(orgs),
+      succeeded: successes,
+      failed: length(failures),
+      failures: failures
+    }
+  end
+
   defp update_billing_sync(organization, device_count) do
     organization
     |> Organization.changeset(%{
diff --git a/test/towerops/billing_test.exs b/test/towerops/billing_test.exs
index 7d5c1507..335dced7 100644
--- a/test/towerops/billing_test.exs
+++ b/test/towerops/billing_test.exs
@@ -451,4 +451,99 @@ defmodule Towerops.BillingTest do
       assert Billing.stripe_price_id() == "price_test_fake"
     end
   end
+
+  describe "migrate_all_subscriptions_to_price/1" do
+    test "migrates all active subscriptions and reports results" do
+      # Create test orgs with active subscriptions
+      user = user_fixture()
+      _org1 = organization_fixture(user.id, %{subscription_status: "active", stripe_subscription_id: "sub_1"})
+      _org2 = organization_fixture(user.id, %{subscription_status: "active", stripe_subscription_id: "sub_2"})
+      org3 = organization_fixture(user.id, %{subscription_status: "active", stripe_subscription_id: "sub_3"})
+      _org4 = organization_fixture(user.id, %{subscription_status: "canceled", stripe_subscription_id: "sub_4"})
+
+      # Mock Stripe responses
+      Req.Test.stub(StripeClient, fn conn ->
+        cond do
+          conn.method == "GET" and String.contains?(conn.request_path, "sub_1") ->
+            # GET subscription - success
+            conn
+            |> Plug.Conn.put_resp_content_type("application/json")
+            |> Plug.Conn.send_resp(
+              200,
+              Jason.encode!(%{
+                "id" => "sub_1",
+                "items" => %{"data" => [%{"id" => "si_1", "price" => %{"id" => "price_old"}}]}
+              })
+            )
+
+          conn.method == "POST" and String.contains?(conn.request_path, "sub_1") ->
+            # POST update - success
+            conn
+            |> Plug.Conn.put_resp_content_type("application/json")
+            |> Plug.Conn.send_resp(200, Jason.encode!(%{"id" => "sub_1"}))
+
+          conn.method == "GET" and String.contains?(conn.request_path, "sub_2") ->
+            # GET subscription - success
+            conn
+            |> Plug.Conn.put_resp_content_type("application/json")
+            |> Plug.Conn.send_resp(
+              200,
+              Jason.encode!(%{
+                "id" => "sub_2",
+                "items" => %{"data" => [%{"id" => "si_2", "price" => %{"id" => "price_old"}}]}
+              })
+            )
+
+          conn.method == "POST" and String.contains?(conn.request_path, "sub_2") ->
+            # POST update - success
+            conn
+            |> Plug.Conn.put_resp_content_type("application/json")
+            |> Plug.Conn.send_resp(200, Jason.encode!(%{"id" => "sub_2"}))
+
+          conn.method == "GET" and String.contains?(conn.request_path, "sub_3") ->
+            # GET subscription - success (but update will fail)
+            conn
+            |> Plug.Conn.put_resp_content_type("application/json")
+            |> Plug.Conn.send_resp(
+              200,
+              Jason.encode!(%{
+                "id" => "sub_3",
+                "items" => %{"data" => [%{"id" => "si_3", "price" => %{"id" => "price_old"}}]}
+              })
+            )
+
+          conn.method == "POST" and String.contains?(conn.request_path, "sub_3") ->
+            # POST update - failure
+            conn
+            |> Plug.Conn.put_resp_content_type("application/json")
+            |> Plug.Conn.send_resp(
+              400,
+              Jason.encode!(%{"error" => %{"message" => "Subscription cannot be modified"}})
+            )
+
+          true ->
+            conn
+            |> Plug.Conn.put_resp_content_type("application/json")
+            |> Plug.Conn.send_resp(404, Jason.encode!(%{}))
+        end
+      end)
+
+      result = Billing.migrate_all_subscriptions_to_price("price_new123")
+
+      assert result.total == 3
+      assert result.succeeded == 2
+      assert result.failed == 1
+      assert length(result.failures) == 1
+      assert [{:error, ^org3, _reason}] = result.failures
+    end
+
+    test "returns empty results when no active subscriptions" do
+      result = Billing.migrate_all_subscriptions_to_price("price_new123")
+
+      assert result.total == 0
+      assert result.succeeded == 0
+      assert result.failed == 0
+      assert result.failures == []
+    end
+  end
 end