game.rap

proc GAME ()
    extern: GAME_START, YOUR_TURN, MY_TURN, WRONG
    intern: RIDDLE, MIN, MAX, YOU_GUESSED, I_GUESSED
    output: "Who'll guess first?"
    GAME_START()
    do
        output: "Your turn:"; YOUR_TURN()
        output: "My turn."; MY_TURN()
        case
            when YOU_GUESSED and I_GUESSED:
                output: "Nobody won!"
            when YOU_GUESSED:
                output: "You won!"
            when I_GUESSED:
                output: "I won!"
        esac
        if YOU_GUESSED or I_GUESSED then
            return
        fi
    until WRONG()

    output: "You've missed somewhere!"
    output: "I don't want to play anymore."
end

proc GAME_START ()
    extern: RIDDLE, MIN, MAX, YOU_GUESSED, I_GUESSED
    output: "Think of a number from 1 to 1000"
    output: "and try to guess mine"
    RIDDLE      := int_rand(1000)
    MIN         := 0
    MAX         := 1001
    YOU_GUESSED := no
    I_GUESSED   := no
end

proc YOUR_TURN ()
    extern: RIDDLE, YOU_GUESSED
    intern: ATTEMPT
    input: ATTEMPT
    case
        when ATTEMPT>RIDDLE:
            output: "My number is less!"
        when ATTEMPT<RIDDLE:
            output: "My number is greater!"
    esac
    YOU_GUESSED:= (ATTEMPT = RIDDLE)
end

proc MY_TURN ()
    extern: MIN, MAX, I_GUESSED
    intern: ATTEMPT, ANSWER, ANSWER_CORRECT
    ATTEMPT:= (MIN+MAX) // 2
    output: "Is it ", ATTEMPT, "?"
    do
        output: "Answers: =, > (riddle>", ATTEMPT, "), < (riddle<", ATTEMPT, ")"
        input text: ANSWER
        ANSWER_CORRECT:= yes
        case ANSWER
            when ">":   MIN         := ATTEMPT
            when "<":   MAX         := ATTEMPT
            when "=":   I_GUESSED   := yes
            else        ANSWER_CORRECT:= no
                        output:"You did a mistake"
        esac
    until ANSWER_CORRECT
end

fun WRONG ()
    extern: MAX, MIN
    return MIN+1=MAX
end

GAME()