case-whenのインデントは無し
case plan when :plan_a ...do something when :plan_b ...do something end
ではなく
case plan when :plan_a ...do something when :plan_b ...do something end
case plan when :plan_a ...do something when :plan_b ...do something end
ではなく
case plan when :plan_a ...do something when :plan_b ...do something end