What does it mean to have a full moon and reflect the joy of autumn night?

Your heart should be as full of hope as the moon, and you should spend the Mid-Autumn Festival happily. With a full moon, it reflects the joy of autumn night. This sentence comes from a message from Fu Jiying Calligraphy Studio wishing a happy Mid-Autumn Festival. With a full moon, reflecting the joy of autumn night means that the heart should be as full of hope as the moon, and the Mid-Autumn Festival should be spent happily. Sacrificing the moon to admire it and remembering it expressed people's good wishes.