What are the origins, customs, legends, poems and two-part allegorical sayings of Mid-Autumn Festival? Simple, but comprehensive.

The origin of Mid-Autumn Festival was explained by Ouyang Zhan in Tang Dynasty: Autumn is between the two seasons in Xia Dong, August is in the middle of autumn, and 15th is the half month of August, hence the name. Folk commonly known as August Festival. Custom: China has the custom of eating moon cakes, enjoying the moon and visiting Yue Bai during the Mid-Autumn Festival. But the most popular thing is to enjoy the moon. On the Mid-Autumn Festival, Jiangsu people entertain their relatives who come home with moon cakes. This custom has a long history and later spread to the whole country. Moon cakes are also called reunion cakes. Family reunion in Mid-Autumn Festival is a long-standing custom, so it is commonly known as Reunion Festival. In addition, there is a custom legend of watching the tide in the Mid-Autumn Festival: regarding the origin of moon cakes, there is a legend that Emperor Qianlong went down to the south of the Yangtze River and swam to Hangzhou during the Mid-Autumn Festival. Someone offered cookies, and while enjoying the moon, Ganlong repeatedly praised: good moon cakes are good nights in the Mid-Autumn Festival. Since then, cookies have become moon cakes. According to "Dragon City Story", in the sixth year of Tang Kaiyuan, Emperor Xuanzong of Tang Dynasty sleepwalked in Guanghan Palace and saw ten immortals wearing gorgeous clothes singing and dancing under the laurel tree. Xuanzongsu interprets the melody, then remembers its sound and composes it into sound, which is the origin of the famous music score of Nishang Yuyi Dance. Poem: Su Shi's famous sentence, others have not been found, and there are no two-part allegorical sayings.