defmodule Mv.Membership.MemberGroupPoliciesTest do
  @moduledoc """
  Tests for MemberGroup resource authorization policies.

  Verifies own_data can only read linked member's associations;
  read_only can read all, cannot create/destroy;
  normal_user and admin can read, create, destroy.
  """
  use Mv.DataCase, async: false

  alias Mv.Membership
  alias Mv.Accounts
  alias Mv.Authorization

  require Ash.Query

  setup do
    system_actor = Mv.Helpers.SystemActor.get_system_actor()
    %{actor: system_actor}
  end

  defp create_role_with_permission_set(permission_set_name, actor) do
    role_name = "Test Role #{permission_set_name} #{System.unique_integer([:positive])}"

    case Authorization.create_role(
           %{
             name: role_name,
             description: "Test role for #{permission_set_name}",
             permission_set_name: permission_set_name
           },
           actor: actor
         ) do
      {:ok, role} -> role
      {:error, error} -> raise "Failed to create role: #{inspect(error)}"
    end
  end

  defp create_user_with_permission_set(permission_set_name, actor) do
    role = create_role_with_permission_set(permission_set_name, actor)

    {:ok, user} =
      Accounts.User
      |> Ash.Changeset.for_create(:register_with_password, %{
        email: "user#{System.unique_integer([:positive])}@example.com",
        password: "testpassword123"
      })
      |> Ash.create(actor: actor)

    {:ok, user} =
      user
      |> Ash.Changeset.for_update(:update, %{})
      |> Ash.Changeset.manage_relationship(:role, role, type: :append_and_remove)
      |> Ash.update(actor: actor)

    {:ok, user_with_role} = Ash.load(user, :role, domain: Mv.Accounts, actor: actor)
    user_with_role
  end

  defp create_admin_user(actor) do
    create_user_with_permission_set("admin", actor)
  end

  defp create_member_fixture(actor) do
    admin = create_admin_user(actor)

    {:ok, member} =
      Membership.create_member(
        %{
          first_name: "Test",
          last_name: "Member",
          email: "test#{System.unique_integer([:positive])}@example.com"
        },
        actor: admin
      )

    member
  end

  defp create_group_fixture(actor) do
    admin = create_admin_user(actor)

    {:ok, group} =
      Membership.create_group(
        %{name: "Test Group #{System.unique_integer([:positive])}", description: "Test"},
        actor: admin
      )

    group
  end

  defp create_member_group_fixture(member_id, group_id, actor) do
    admin = create_admin_user(actor)

    {:ok, member_group} =
      Membership.create_member_group(%{member_id: member_id, group_id: group_id}, actor: admin)

    member_group
  end

  describe "own_data permission set" do
    setup %{actor: actor} do
      user = create_user_with_permission_set("own_data", actor)
      member = create_member_fixture(actor)
      group = create_group_fixture(actor)
      # Link user to member so actor.member_id is set
      admin = create_admin_user(actor)

      user =
        user
        |> Ash.Changeset.for_update(:update, %{})
        |> Ash.Changeset.force_change_attribute(:member_id, member.id)
        |> Ash.update(actor: admin)

      {:ok, user} = Ash.load(user, :role, domain: Mv.Accounts, actor: actor)
      mg_linked = create_member_group_fixture(member.id, group.id, actor)
      # MemberGroup for another member (not linked to user)
      other_member = create_member_fixture(actor)
      other_group = create_group_fixture(actor)
      mg_other = create_member_group_fixture(other_member.id, other_group.id, actor)
      %{user: user, member: member, group: group, mg_linked: mg_linked, mg_other: mg_other}
    end

    test "can read member_groups for linked member only", %{user: user, mg_linked: mg_linked} do
      {:ok, list} =
        Mv.Membership.MemberGroup
        |> Ash.read(actor: user, domain: Mv.Membership)

      ids = Enum.map(list, & &1.id)
      assert mg_linked.id in ids
      refute Enum.empty?(list)
    end

    test "list returns only member_groups where member_id == actor.member_id", %{
      user: user,
      mg_linked: mg_linked,
      mg_other: mg_other
    } do
      {:ok, list} =
        Mv.Membership.MemberGroup
        |> Ash.read(actor: user, domain: Mv.Membership)

      ids = Enum.map(list, & &1.id)
      assert mg_linked.id in ids
      refute mg_other.id in ids
    end

    test "cannot create member_group (returns forbidden)", %{user: user, actor: actor} do
      # Use fresh member/group so we assert on Forbidden, not on duplicate validation
      other_member = create_member_fixture(actor)
      other_group = create_group_fixture(actor)

      assert {:error, %Ash.Error.Forbidden{}} =
               Membership.create_member_group(
                 %{member_id: other_member.id, group_id: other_group.id},
                 actor: user
               )
    end

    test "cannot destroy member_group (returns forbidden)", %{user: user, mg_linked: mg_linked} do
      assert {:error, %Ash.Error.Forbidden{}} =
               Membership.destroy_member_group(mg_linked, actor: user)
    end
  end

  describe "read_only permission set" do
    setup %{actor: actor} do
      user = create_user_with_permission_set("read_only", actor)
      member = create_member_fixture(actor)
      group = create_group_fixture(actor)
      mg = create_member_group_fixture(member.id, group.id, actor)
      %{actor: actor, user: user, member: member, group: group, mg: mg}
    end

    test "can read all member_groups", %{user: user, mg: mg} do
      {:ok, list} =
        Mv.Membership.MemberGroup
        |> Ash.read(actor: user, domain: Mv.Membership)

      ids = Enum.map(list, & &1.id)
      assert mg.id in ids
    end

    test "cannot create member_group (returns forbidden)", %{user: user, actor: actor} do
      member = create_member_fixture(actor)
      group = create_group_fixture(actor)

      assert {:error, %Ash.Error.Forbidden{}} =
               Membership.create_member_group(%{member_id: member.id, group_id: group.id},
                 actor: user
               )
    end

    test "cannot destroy member_group (returns forbidden)", %{user: user, mg: mg} do
      assert {:error, %Ash.Error.Forbidden{}} =
               Membership.destroy_member_group(mg, actor: user)
    end
  end

  describe "normal_user permission set" do
    setup %{actor: actor} do
      user = create_user_with_permission_set("normal_user", actor)
      member = create_member_fixture(actor)
      group = create_group_fixture(actor)
      mg = create_member_group_fixture(member.id, group.id, actor)
      %{actor: actor, user: user, member: member, group: group, mg: mg}
    end

    test "can read all member_groups", %{user: user, mg: mg} do
      {:ok, list} =
        Mv.Membership.MemberGroup
        |> Ash.read(actor: user, domain: Mv.Membership)

      ids = Enum.map(list, & &1.id)
      assert mg.id in ids
    end

    test "can create member_group", %{user: user, actor: actor} do
      member = create_member_fixture(actor)
      group = create_group_fixture(actor)

      assert {:ok, _mg} =
               Membership.create_member_group(%{member_id: member.id, group_id: group.id},
                 actor: user
               )
    end

    test "can destroy member_group", %{user: user, mg: mg} do
      assert :ok = Membership.destroy_member_group(mg, actor: user)
    end
  end

  describe "admin permission set" do
    setup %{actor: actor} do
      user = create_user_with_permission_set("admin", actor)
      member = create_member_fixture(actor)
      group = create_group_fixture(actor)
      mg = create_member_group_fixture(member.id, group.id, actor)
      %{actor: actor, user: user, member: member, group: group, mg: mg}
    end

    test "can read all member_groups", %{user: user, mg: mg} do
      {:ok, list} =
        Mv.Membership.MemberGroup
        |> Ash.read(actor: user, domain: Mv.Membership)

      ids = Enum.map(list, & &1.id)
      assert mg.id in ids
    end

    test "can create member_group", %{user: user, actor: actor} do
      member = create_member_fixture(actor)
      group = create_group_fixture(actor)

      assert {:ok, _mg} =
               Membership.create_member_group(%{member_id: member.id, group_id: group.id},
                 actor: user
               )
    end

    test "can destroy member_group", %{user: user, mg: mg} do
      assert :ok = Membership.destroy_member_group(mg, actor: user)
    end
  end
end