high-low.php

<?php

# Colours
function green($text) {
    return "\e[0;32m$text\e[0m";
}

function yellow($text) {
    return "\e[0;33m$text\e[0m";
}

function red($text) {
    return "\e[0;31m$text\e[0m";
}

function white_bold($text) {
    return "\e[1;37m$text\e[0m";
}

$limit = 10;

# Assign the script's choices to an array
$choices = [];
for ($i = 1; $i < $limit ; $i++) {
    $choices[] = $i;
}

# Unset the first and last number
unset($choices[0]);
unset($choices[$limit-2]);

$streak = true;

# While the user has a streak
while ($streak == true) {
    # Pick a random number from the choices
    $new = $choices[array_rand($choices)];
    $old = $new;
    # Ensure the new and old numbers don't match
    while ($new == $old) {
        $old = $choices[array_rand($choices)];
    }

    # If the new number is higher than the old
    if ($old < $new) {
        $correct = 'high';
    } else {
        $correct = 'low';
    }

    # Colour the user's streak depending on how high it is
    if ($streak < 4) {
        echo "Streak is: " . red($streak-1) . "\n";
    } elseif ($streak >= 4 && $streak < 6) {
        echo "Streak is: " . yellow($streak-1) . "\n";
    } else {
        echo "Streak is: " . green($streak-1) . "\n";
    }

    echo "Number is: " . white_bold($old) . " (/" . ($limit-1) . ").\nHigher or lower?\n";
    $input = readline('> ');

    $sanitised = false;

    while (!$sanitised) {
        # If there are numbers
        if (preg_match('/[0-9]/', $input)) {
            echo "No numbers.\n";
            $input = readline('> ');
        # If there are symbols
        } elseif (preg_match('/[^\p{L}\d\s@#]/u', $input)) {
            echo "No symbols.\n";
            $input = readline('> ');
        # If there is no input
        } elseif ($input == null) {
            echo "Enter 'high' or 'low'.\n";
            $input = readline('> ');
        } else {
            # If there are just letters (if logic makes this so)
            if (preg_match('/[a-z]/', $input)) {
                # If the input is high or low
                if ($input == 'high' || $input == 'low') {
                    # End the loop
                    $sanitised = true;
                } else {
                    echo "Enter 'high' or 'low'.\n";
                    $input = readline('> ');
                }
            }
        }
    }

    if ($input == $correct) {
        echo "Correct!\n";
        $streak += 1;
    } else {
        echo "Incorrect.\n";
        $streak = 0;
    }
}