# prchecks - print formatted checks
#   input:  number \t amount \t payee
#   output: eight lines of text for preprinted check forms

BEGIN {
    FS = "\t"
    dashes = sp45 = sprintf("%45s", " ")
    gsub(/ /, "-", dashes)        # to protect the payee
    "date" | getline date         # get today's date
    split(date, d, " ")
    date = d[2] " " d[3] ", " d[6]
    initnum()    # set up tables for number conversion
}
NF != 3 || $2 >= 1000000 {        # illegal data
    printf("\nline %d illegal:\n%s\n\nVOID\nVOID\n\n\n", NR, $0)
    next                          # no check printed
}
{   printf("\n")                  # nothing on line 1
    printf("%s%s\n", sp45, $1)    # number, indented 45 spaces
    printf("%s%s\n", sp45, date)  # date, indented 45 spaces
    amt = sprintf("%.2f", $2)     # formatted amount
    printf("Pay to %45.45s   $%s\n", $3 dashes, amt)  # line 4
    printf("the sum of %s\n", numtowords(amt))        # line 5
    printf("\n\n\n")              # lines 6, 7 and 8
}

function numtowords(n,   cents, dols) { # n has 2 decimal places
    cents = substr(n, length(n)-1, 2)
    dols = substr(n, 1, length(n)-3)
    if (dols == 0)
        return "zero dollars and " cents " cents exactly"
    return intowords(dols) " dollars and " cents " cents exactly"
}

function intowords(n) {
    n = int(n)
    if (n >= 1000)
        return intowords(n/1000) " thousand " intowords(n%1000)
    if (n >= 100)
        return intowords(n/100) " hundred " intowords(n%100)
    if (n >= 20)
        return tens[int(n/10)] " " intowords(n%10)
    return nums[n]
}

function initnum() {
    split("one two three four five six seven eight nine " \
 			prchecks           "ten eleven twelve thirteen fourteen fifteen " \
 			prchecks           "sixteen seventeen eighteen nineteen", nums, " ")
    split("ten twenty thirty forty fifty sixty " \
 	 prchecks           "seventy eighty ninety", tens, " ")
}