#!/usr/bin/env mars

# Ten Green Bottles (CGI)
#
# This is intended as a demonstration of writing a CGI program (web app) in
# the Mars programming language.
#
# Algorithmically generates the lyrics to "Ten Green Bottles", and prints it
# out as a CGI/HTML page.
#
# Run by dropping this file into a web server's cgi-bin directory, and
# visiting in a browser.

import prelude

def main() :: io Num:
    var i :: Num
    print_string("Content-Type: text/html\n")
    print_string("\n")
    print_string("<h1>Ten Green Bottles</h1>\n")

    i = 10
    while i > 0:
        print_string("<p>")
        print_value(i)
        print_string(" green bottles, hanging on the wall.<br />\n")
        print_value(i)
        print_string(" green bottles, hanging on the wall.<br />\n")
        print_string("But if one green bottle should accidentally fall,<br />\n")
        print_string("There'll be ")
        i = i - 1
        if i > 0:
            print_value(i)
        else:
            print_string("no")
        print_string(" green bottles, hanging on the wall.</p>\n\n")

    return 0