
_A wrong guess ('henry') triggers the 'Wrong input' message, set against the app's glyph background, which changes color and glyphs on each reload_

A while back, I created a little game with vanilla `JavaScript` revolving around
the `keypress` event that might end up being reused one day in a bigger project.
There was a lot more going on under the hood than met the eye, and I learned a
new thing or two in the process. So I thought it was time to write another post!

The game's code lives across `index.mjs` and eight small modules in a
`modules` folder, some of which handle `CSS` in `JS` and the rest of which
handle the `keypress` and `input` validation. There are two parts to the
`game`.

The first part is to guess the keys you should press in order that a phrase from
a song appears in a colored box with a dashed border above the text "Answer".
This can be achieved two ways. You can either press keys over the text document
(browser window) to make the colored box with phrases from songs appear, or you
can type directly into the input field.

The second part consists of rendering "Your input is correct!" above the text
"Answer", and replacing "Answer" with "You guessed correctly. It is ...!" There
are only a certain number of song phrases, and each corresponds to a certain
keypress. Those keypresses are equivalent to a string that makes up a name or
word. If you correctly type that sequence into the input field and press return,
you will receive a message letting you know that you guessed correctly followed
by the answer. In addition, after you press "return", the input field is
disabled, and you can no longer type into it. You can keep on typing into the
input with incorrect characters after inputting the correct string, but nothing
happens. When you think you have the right answer, make sure to press the
"return" key.

If you type the correct keypresses or sequence of keypresses to the document,
you will render the song phrases to the page. However, when you press the
"return" key, you will receive the error message "Wrong input. Try again!" in
the colored box, and "Answer" will be replaced with the error message "You
guessed incorrectly. Try again!".

How I achieved this game via `JavaScript` code can be broken down into five
important highlights.

- Adding an `input.value` condition not equal to the "Answer".

- Adding an `else statement/condition` not equal to the "Answer".

- Adding an `input.value condition` not equal to the "Answer" to the `input`
  change event.

- Adding `input.disabled` equal to `true` to the `else` statement for
  `input.value condition` equal to "Answer" in the `input` change event.

- Adding page refresh code to the "click event" for the button.

At first I didn't add an `input` value condition to the `keypress listener`. I
had all these conditions for the keypresses and then an `else` statement which
simply returned the error message "Wrong input. Try again!", but no condition
against the correct answer which is supposed to be typed into the `input`. I
added another `else if` condition after the first `if` and subsequent `else if`
conditions for the individual keypresses associated with the songs that checked
against an incorrect `input` value. This would result in the error message
"Wrong input. Try again!" rendered to the colored box, and the error message
"You guessed incorrectly. Try again!" that replaces the text "Answer". This
`else if` statement is then followed by the final `else` statement which returns
the confirmation messages "Your input is correct!" and `You guessed correctly.
It is ...!"

I added a `disabled.true` property to the `input` if the "Answer" is correct and
the user presses `return` after inputting it. This is so that no incorrect
characters can be rendered to the colored box after the correct answer has been
inputted and the `return` key has been pressed.

Lastly, I had to add a way to refresh the page so that `disabled.true` is erased
and the user can type in the input field again.

Since first writing this post, I went back and updated the project. The build
now runs on `Vite` instead of `Webpack`, which also replaced the manual `SCSS`
setup that was there before. I added a test suite for the game logic using
`Vitest`, with coverage tracked through `Istanbul`. The suite covers eight
modules across 17 tests, and coverage currently sits at 100% across
statements, branches, functions, and lines.

The background styling from this project turned out to be reusable elsewhere.
I pulled the same background-related modules into this site, where they now
power the animated backgrounds on the About, Resume, and Contact pages.

I didn't share code here on purpose because that would spoil the game for you!
Please do check it out on `Github`, and give it a whirl! And let me know what
you think!


A fun little game made with JavaScript, SCSS/CSS3, and HTML.

projects tag: istanbul

Guess the Keys App