Bejeweled

In this project, you will create a command-line Bejeweled game. Unlike previous projects, you will be start by implementing test specs in bejeweled-spec.js for the game logic. Once these specs are in place, you can implement the game logic in bejeweled.js.

To render the game, you have been given a Screen API that handles command-line rendering. You do not need to understand how the code in Screen works but you will need to make use of the commands provided. The API is documented below. Try out the commands to see how they work.

To process keypresses, you will need to load Command objects into the Screen API using Screen.addCommand. This function takes a key which triggers the command, a string description, and an action callback which is executed when key is pressed.

In order to swap items, you will need to add extra cursor controls: one to select an item and one to execute the swap. You can only swap adjacent items.

Bejeweled rules

Bejeweled is a game that requires you to match three of the same item in a row either horizontally or vertically by swapping items. When you do this, the matched items disappear and new items above it fall to fill the gaps.

Example:

 🥝 🍓 🥥 🍇 🍊 🍇 🥝 🍇 🍊

Swapping the middle 🍊 with the 🍇 below it will match three 🍇 in a row.

 🥝 🍓 🥥
         
 🥝 🍊 🍊

The 🍇s disappear new items fall in from the top to fill in the blank spots.

 🥝 🍋 🍊 🥝 🍓 🥥 🥝 🍊 🍊

In this case, a new 🥝 fell down, triggering a combo.

    🍋 🍊 🍓 🥥 🍊 🍊

Again, new items fall in to replace the completed 🥝s.

 🍓 🍋 🍊 🍇 🍓 🥥 🍋 🍊 🍊

There are no more matches, so the player can take their next turn.

Running the game

1. Type npm install to install all packages
2. Run node game.js to run the game
3. Run mocha to run tests

Tasks

1. Implement tests in test/bejeweled-spec.js matching the bejeweled game logic
2. Update tests in test/cursor-spec.js to handle selecting and swapping gems
3. Fill out game logic in class/bejeweled.js until mocha test/bejeweled-spec.js passes all tests
4. Update cursor logic in class/cursor.js until mocha test/cursor-spec.js passes all tests
5. Use setBackgroundColor and resetBackgroundColor in cursor.js to highlight the cursor's current position on the grid, with a visual signifier when the cursor is in a "swap" state
6. Create commands in bejeweled.js to select gems and execute swaps
7. Fill out the game state in bejeweled.js that checks for match-3s.
8. Chain the game state to check and alert the player for match combos.
9. Implement a score for the player based on matches and combos.

Screen API

Screen is a static class with the following methods. You do not need to modify this class at all. The functionality you will need is documented below.

Initialize

• Screen.initialize(numRows, numCols) will initialize a grid with the given dimensions.

Initialize

• Screen.setGridlines(gridLines) will insert lines between each grid element is gridLines is true, or hide them if gridLines is false.

Commands

• Screen.addCommand(key, description, action) will add a command that calls the action callback anytime key is typed on the keyboard. description will be displayed in the help message.
• Screen.printCommands() will show a list of all loaded commands and their descriptions.

Updating the grid

• Screen.setGrid(row, col, char) sets the character at row and col to the given char.
• Screen.setTextColor(row, col, color) sets the text color at row and col to the given color.
• Screen.setBackgroundColor(row, col, color) sets the background color at row and col to the given color.

Valid colors are:

• black
• red
• green
• yellow
• blue
• cyan
• white
• magenta

Quitting

• Screen.setQuitMessage(quitMessage) sets a message to be printed when the user quits.
• Screen.quit(showMessage=true) quits the game and prints the message if showMessage is true.

Rendering

• Screen.render() will update the display. This must be called anytime the grid or messages change.

Displaying a message

• Screen.setMessage(msg) takes in a string to be printed below the grid each time it is rendered.