Next.js getStaticProps Function: Fetching Data for Dynamic Pages

This function implements the Next.js 'getStaticProps' API, used to fetch data and pass it as props to a React component during the build time.

It first checks if the 'params' object and the 'slug' parameter exist. If not, it returns a 'notFound' property with a value of 'true', telling Next.js to return a 404 page.

If they exist, the function converts the slug from a comma-separated string to a forward-slash-separated string and removes the '.html' extension.

Then, it fetches all the posts and finds the current post based on the slug. It also retrieves the previous and next posts based on their index in the 'posts' array.

After that, it fetches the data for the current post using two functions: 'getPostData' and 'chatGPTData'.

Finally, it retrieves the total number of posts and the total word count using the 'total' function and passes all the data as props to the component.