Suppose I have a dataframe:

df <- data.frame(
  x = c("Yes","No","Yes","Don't Know"),
  y = c("Male","Female","Refused","Male"),
  z = c("Employed", "Unemployed","Employed","Employed")
)

I want to recode the values in the entire dataframe to numeric values and have the codes stored in a separate dataframe:

codes <- data.frame(
  variable = c(rep("x",3),rep("y",3),rep("z",2)),
  labels = c("Yes","No","Don't Know","Male","Female","Refused","Employed", "Unemployed"),
  codes = c(1,2,98,1,2,99,1,2)
)

I want to output to look like:

> df
   x  y z
1  1  1 1
2  2  2 2
3  1 99 1
4 98  1 1

How can I approach this problem? A tidyverse solution would be very helpful.