From 50257dbe68d56452dd30d512ff29ea5e4906a8c2 Mon Sep 17 00:00:00 2001
From: Graham McIntire <graham@mcintire.me>
Date: Tue, 3 Feb 2026 13:20:33 -0600
Subject: [PATCH] more tests

---
 lib/towerops/result.ex                        |   6 +-
 test/towerops/result_test.exs                 | 172 ++++++++++++++++++
 .../plugs/remote_ip_logger_test.exs           |  83 +++++++++
 .../plugs/update_session_activity_test.exs    | 111 +++++++++++
 4 files changed, 369 insertions(+), 3 deletions(-)
 create mode 100644 test/towerops/result_test.exs
 create mode 100644 test/towerops_web/plugs/remote_ip_logger_test.exs
 create mode 100644 test/towerops_web/plugs/update_session_activity_test.exs

diff --git a/lib/towerops/result.ex b/lib/towerops/result.ex
index d53fa588..7cd07abf 100644
--- a/lib/towerops/result.ex
+++ b/lib/towerops/result.ex
@@ -72,10 +72,10 @@ defmodule Towerops.Result do
 
   ## Examples
 
-      iex> Result.and_then({:ok, user}, fn u -> {:ok, u.email} end)
-      {:ok, "user@example.com"}
+      iex> Result.and_then({:ok, 10}, fn x -> {:ok, x * 2} end)
+      {:ok, 20}
 
-      iex> Result.and_then({:error, :not_found}, fn u -> {:ok, u.email} end)
+      iex> Result.and_then({:error, :not_found}, fn x -> {:ok, x * 2} end)
       {:error, :not_found}
   """
   @spec and_then(t(a, e), (a -> t(b, e))) :: t(b, e) when a: var, b: var, e: var
diff --git a/test/towerops/result_test.exs b/test/towerops/result_test.exs
new file mode 100644
index 00000000..a6674f9f
--- /dev/null
+++ b/test/towerops/result_test.exs
@@ -0,0 +1,172 @@
+defmodule Towerops.ResultTest do
+  use ExUnit.Case, async: true
+
+  alias Towerops.Result
+
+  doctest Result
+
+  describe "map/2" do
+    test "applies function to success value" do
+      assert Result.map({:ok, 5}, fn x -> x * 2 end) == {:ok, 10}
+      assert Result.map({:ok, "hello"}, &String.upcase/1) == {:ok, "HELLO"}
+    end
+
+    test "passes through error unchanged" do
+      assert Result.map({:error, :not_found}, fn x -> x * 2 end) == {:error, :not_found}
+      assert Result.map({:error, "failure"}, &String.upcase/1) == {:error, "failure"}
+    end
+
+    test "works with complex transformations" do
+      result = {:ok, %{name: "John", age: 30}}
+      assert Result.map(result, fn user -> user.name end) == {:ok, "John"}
+    end
+  end
+
+  describe "map_error/2" do
+    test "applies function to error value" do
+      assert Result.map_error({:error, :timeout}, fn _ -> :network_error end) ==
+               {:error, :network_error}
+
+      assert Result.map_error({:error, "db_error"}, &String.upcase/1) == {:error, "DB_ERROR"}
+    end
+
+    test "passes through success unchanged" do
+      assert Result.map_error({:ok, 42}, fn _ -> :network_error end) == {:ok, 42}
+      assert Result.map_error({:ok, "success"}, &String.upcase/1) == {:ok, "success"}
+    end
+
+    test "works with complex error transformations" do
+      result = {:error, %{code: 500, message: "Internal Error"}}
+
+      assert Result.map_error(result, fn err -> err.code end) == {:error, 500}
+    end
+  end
+
+  describe "and_then/2" do
+    test "chains successful operations" do
+      result = {:ok, 5}
+
+      assert Result.and_then(result, fn x -> {:ok, x * 2} end) == {:ok, 10}
+    end
+
+    test "stops on first error" do
+      result = {:error, :not_found}
+
+      assert Result.and_then(result, fn x -> {:ok, x * 2} end) == {:error, :not_found}
+    end
+
+    test "propagates error from chained function" do
+      result = {:ok, 5}
+
+      assert Result.and_then(result, fn _ -> {:error, :invalid} end) == {:error, :invalid}
+    end
+
+    test "works with nested operations" do
+      result = {:ok, 10}
+
+      final_result =
+        result
+        |> Result.and_then(fn x -> {:ok, x + 5} end)
+        |> Result.and_then(fn x -> {:ok, x * 2} end)
+        |> Result.and_then(fn x -> {:ok, "Result: #{x}"} end)
+
+      assert final_result == {:ok, "Result: 30"}
+    end
+
+    test "short-circuits on error in chain" do
+      result = {:ok, 10}
+
+      final_result =
+        result
+        |> Result.and_then(fn x -> {:ok, x + 5} end)
+        |> Result.and_then(fn _ -> {:error, :failed} end)
+        |> Result.and_then(fn x -> {:ok, x * 2} end)
+
+      assert final_result == {:error, :failed}
+    end
+  end
+
+  describe "unwrap_or/2" do
+    test "returns success value when ok" do
+      assert Result.unwrap_or({:ok, 42}, 0) == 42
+      assert Result.unwrap_or({:ok, "hello"}, "default") == "hello"
+    end
+
+    test "returns default value on error" do
+      assert Result.unwrap_or({:error, :not_found}, 0) == 0
+      assert Result.unwrap_or({:error, "failure"}, "default") == "default"
+    end
+
+    test "works with nil values" do
+      assert Result.unwrap_or({:ok, nil}, "default") == nil
+      assert Result.unwrap_or({:error, :not_found}, nil) == nil
+    end
+
+    test "works with complex default values" do
+      default = %{name: "Unknown", age: 0}
+      assert Result.unwrap_or({:error, :not_found}, default) == default
+    end
+  end
+
+  describe "ok?/1" do
+    test "returns true for success" do
+      assert Result.ok?({:ok, 42}) == true
+      assert Result.ok?({:ok, nil}) == true
+      assert Result.ok?({:ok, []}) == true
+    end
+
+    test "returns false for error" do
+      assert Result.ok?({:error, :not_found}) == false
+      assert Result.ok?({:error, "failure"}) == false
+      assert Result.ok?({:error, nil}) == false
+    end
+  end
+
+  describe "error?/1" do
+    test "returns true for error" do
+      assert Result.error?({:error, :not_found}) == true
+      assert Result.error?({:error, "failure"}) == true
+      assert Result.error?({:error, nil}) == true
+    end
+
+    test "returns false for success" do
+      assert Result.error?({:ok, 42}) == false
+      assert Result.error?({:ok, nil}) == false
+      assert Result.error?({:ok, []}) == false
+    end
+  end
+
+  describe "combined operations" do
+    test "map and and_then together" do
+      result = {:ok, "5"}
+
+      final_result =
+        result
+        |> Result.map(&String.to_integer/1)
+        |> Result.and_then(fn x -> {:ok, x * 2} end)
+        |> Result.map(fn x -> x + 3 end)
+
+      assert final_result == {:ok, 13}
+    end
+
+    test "map_error after failed operation" do
+      result = {:error, :db_timeout}
+
+      final_result =
+        result
+        |> Result.map(fn x -> x * 2 end)
+        |> Result.map_error(fn _ -> :service_unavailable end)
+
+      assert final_result == {:error, :service_unavailable}
+    end
+
+    test "conditional unwrap based on ok?" do
+      success = {:ok, 42}
+      error = {:error, :not_found}
+
+      assert Result.ok?(success) && Result.unwrap_or(success, 0) == 42
+      refute Result.ok?(error)
+      assert Result.unwrap_or(error, 0) == 0
+    end
+  end
+end
diff --git a/test/towerops_web/plugs/remote_ip_logger_test.exs b/test/towerops_web/plugs/remote_ip_logger_test.exs
new file mode 100644
index 00000000..659e0143
--- /dev/null
+++ b/test/towerops_web/plugs/remote_ip_logger_test.exs
@@ -0,0 +1,83 @@
+defmodule ToweropsWeb.Plugs.RemoteIpLoggerTest do
+  use ToweropsWeb.ConnCase, async: true
+
+  alias ToweropsWeb.Plugs.RemoteIpLogger
+
+  require Logger
+
+  describe "init/1" do
+    test "returns options unchanged" do
+      assert RemoteIpLogger.init([]) == []
+      assert RemoteIpLogger.init(some: :option) == [some: :option]
+    end
+  end
+
+  describe "call/2" do
+    test "extracts IP from X-Forwarded-For header" do
+      build_conn()
+      |> put_req_header("x-forwarded-for", "203.0.113.195")
+      |> RemoteIpLogger.call([])
+
+      assert Logger.metadata()[:remote_ip] == "203.0.113.195"
+    end
+
+    test "extracts first IP from comma-separated X-Forwarded-For" do
+      build_conn()
+      |> put_req_header("x-forwarded-for", "203.0.113.195, 10.0.0.1, 192.168.1.1")
+      |> RemoteIpLogger.call([])
+
+      assert Logger.metadata()[:remote_ip] == "203.0.113.195"
+    end
+
+    test "trims whitespace from X-Forwarded-For IP" do
+      build_conn()
+      |> put_req_header("x-forwarded-for", "  203.0.113.195  , 10.0.0.1")
+      |> RemoteIpLogger.call([])
+
+      assert Logger.metadata()[:remote_ip] == "203.0.113.195"
+    end
+
+    test "falls back to X-Real-IP when X-Forwarded-For is not present" do
+      build_conn()
+      |> put_req_header("x-real-ip", "198.51.100.42")
+      |> RemoteIpLogger.call([])
+
+      assert Logger.metadata()[:remote_ip] == "198.51.100.42"
+    end
+
+    test "formats IPv4 from conn.remote_ip when no proxy headers present" do
+      # ConnCase builds a conn with remote_ip {127, 0, 0, 1}
+      RemoteIpLogger.call(build_conn(), [])
+
+      assert Logger.metadata()[:remote_ip] == "127.0.0.1"
+    end
+
+    test "formats IPv6 from conn.remote_ip" do
+      build_conn()
+      |> Map.put(:remote_ip, {8193, 3512, 0, 0, 0, 0, 0, 1})
+      |> RemoteIpLogger.call([])
+
+      # IPv6 formatted as hex segments separated by colons (uppercase)
+      assert Logger.metadata()[:remote_ip] == "2001:DB8:0:0:0:0:0:1"
+    end
+
+    test "prefers X-Forwarded-For over X-Real-IP" do
+      build_conn()
+      |> put_req_header("x-forwarded-for", "203.0.113.195")
+      |> put_req_header("x-real-ip", "198.51.100.42")
+      |> RemoteIpLogger.call([])
+
+      assert Logger.metadata()[:remote_ip] == "203.0.113.195"
+    end
+
+    test "returns conn unchanged" do
+      original_conn = build_conn()
+      result_conn = RemoteIpLogger.call(original_conn, [])
+
+      # Conn should pass through unchanged (only metadata is modified)
+      assert result_conn.adapter == original_conn.adapter
+      assert result_conn.method == original_conn.method
+      assert result_conn.path_info == original_conn.path_info
+    end
+  end
+end
diff --git a/test/towerops_web/plugs/update_session_activity_test.exs b/test/towerops_web/plugs/update_session_activity_test.exs
new file mode 100644
index 00000000..c6d1b4a3
--- /dev/null
+++ b/test/towerops_web/plugs/update_session_activity_test.exs
@@ -0,0 +1,111 @@
+defmodule ToweropsWeb.Plugs.UpdateSessionActivityTest do
+  use ToweropsWeb.ConnCase, async: true
+
+  import Towerops.AccountsFixtures
+
+  alias Towerops.Accounts
+  alias ToweropsWeb.Plugs.UpdateSessionActivity
+
+  describe "init/1" do
+    test "returns options unchanged" do
+      assert UpdateSessionActivity.init([]) == []
+      assert UpdateSessionActivity.init(some: :option) == [some: :option]
+    end
+  end
+
+  describe "call/2" do
+    test "returns conn unchanged" do
+      conn = Plug.Test.init_test_session(build_conn(), %{})
+
+      result = UpdateSessionActivity.call(conn, [])
+
+      assert result == conn
+    end
+
+    test "spawns background task to update session activity" do
+      user = user_fixture()
+      {token, user_token} = Accounts.generate_user_session_token_with_record(user)
+
+      now = DateTime.utc_now()
+
+      # Create browser session
+      {:ok, _session} =
+        Accounts.create_browser_session(%{
+          user_id: user.id,
+          user_token_id: user_token.id,
+          device_name: "Test Browser",
+          ip_address: "127.0.0.1",
+          user_agent: "Mozilla/5.0 Test",
+          last_activity_at: now,
+          expires_at: DateTime.add(now, 30, :day)
+        })
+
+      # Call plug with session token - should spawn background task without blocking
+      result =
+        build_conn()
+        |> Plug.Test.init_test_session(%{user_token: token})
+        |> UpdateSessionActivity.call([])
+
+      # Should return immediately (not block on background task)
+      assert result
+    end
+
+    test "handles missing session token gracefully" do
+      build_conn()
+      |> Plug.Test.init_test_session(%{})
+      |> UpdateSessionActivity.call([])
+
+      # Should not raise an error - test passes if no exception
+    end
+
+    test "handles invalid session token gracefully" do
+      build_conn()
+      |> Plug.Test.init_test_session(%{user_token: "invalid-token-does-not-exist"})
+      |> UpdateSessionActivity.call([])
+
+      # Wait for background task to complete
+      Process.sleep(100)
+
+      # Should not raise an error - test passes if no exception
+    end
+
+    test "does not block the request while updating" do
+      user = user_fixture()
+      {token, user_token} = Accounts.generate_user_session_token_with_record(user)
+
+      now = DateTime.utc_now()
+
+      {:ok, _session} =
+        Accounts.create_browser_session(%{
+          user_id: user.id,
+          user_token_id: user_token.id,
+          device_name: "Test Browser",
+          ip_address: "127.0.0.1",
+          user_agent: "Mozilla/5.0 Test",
+          last_activity_at: now,
+          expires_at: DateTime.add(now, 30, :day)
+        })
+
+      # Time the request - should be fast even though update happens in background
+      start_time = System.monotonic_time(:millisecond)
+
+      build_conn()
+      |> Plug.Test.init_test_session(%{user_token: token})
+      |> UpdateSessionActivity.call([])
+
+      end_time = System.monotonic_time(:millisecond)
+      duration = end_time - start_time
+
+      # Should complete very quickly (under 50ms) since update is async
+      assert duration < 50
+    end
+
+    test "handles nil token gracefully" do
+      build_conn()
+      |> Plug.Test.init_test_session(%{user_token: nil})
+      |> UpdateSessionActivity.call([])
+
+      # Should not raise an error - test passes if no exception
+    end
+  end
+end