There are a lot of possible permutations of just one possible time reference, not to mention all other possibilities.zero to nine in seconds, one to six in minutes and one to twelve for hours.
Twenty,thirty,forty etc
That's just for standard time. Military goes past twelve hundred hours, thirteen hundred hours, ...etc..
Don't forget to include the word zero and the letter O as it's often pronounced "O six forty five" instead of "zero six forty five" Some might include dashes as saparators.
I'm just saying it's going to be a huge task to include all possibilities for a very niche group that might actually put it to use.
By all means, I'm not trying to discourage you...just throwing more wood on the fire.