pseudo code

# firebase pseudo code 

# create a users object

# every object within will be named with the user.id 

# search page 
# only render the favourites button for logged in users 

# we need to pull user's booklist and match the id with the array of books returned from search 
# if the ids match, disable the fav button 

# fav button - use set hook from firebase to update user's fav booklist 


# favourites page 

# use localstorage userid and make a fetch call from database for user's booklist

# useEffect: 
# using a loop, we'll make an axios call for each book.id in user's list 
# use DisplayBooks to render data from firebase

# if favbutton is active and clicked on, remove the book using book.id from user's booklist, using remove()

# if favbutton is not active and clicked on, add the book's id to the user's booklist, using set 

# We can save the completion number in state, and set it equal to the length of the booklist array from firebase

# whenever we check off a book as "read", we take 1 away from the completion number and add a class somewhere "read"

# if user clicks on delete book, and there's a class of "read" on the book, do not take 1 away from completion number


# details page 

# only render the favourites button for logged in users 
# useEffect() => {
#     check if book.id exists in user's booklist 

#     if it is, disable the favourites button 
# }

# we'll replace delete and read buttons with a fav button