PixeLAW Book

Functions

We need following functions:

• init: initialize application settings.
• interact: interact with PixeLAW field. When we start game, we call this function to set up field.
• reveal: reveal the pixel if bomb or not.
• explode: if a player reveals a bomb, this function is called.
• ownerless_space:

We can write interface like this:

#[starknet::interface]
trait IMinesweeperActions<TContractState> {
    fn init(self: @TContractState);
    fn interact(self: @TContractState, default_params: DefaultParameters, size: u64, mines_amount: u64);
    fn reveal(self: @TContractState, default_params: DefaultParameters);
    fn explode(self: @TContractState, default_params: DefaultParameters);
    fn ownerless_space(self: @TContractState, default_params: DefaultParameters, size: u64) -> bool;
}

Set constants

We set some constants. We added GAME_MAX_DURATION to avoid permanent sessions.

/// APP_KEY must be unique across the entire platform
const APP_KEY: felt252 = 'minesweeper';

/// Core only supports unicode icons for now
const APP_ICON: felt252 = 'U+1F4A3'; // bomb

/// prefixing with BASE means using the server's default manifest.json handler
const APP_MANIFEST: felt252 = 'BASE/manifests/minesweeper';

/// The maximum duration of a game in milliseconds
const GAME_MAX_DURATION: u64 = 20000;

We used this to search the unicode icon.

Create enum and struct

We use State and Game. State represents statement of pixel in minesweeper, and Game struct handle the components for this game.

#[derive(Serde, Copy, Drop, PartialEq, Introspect)]
enum State {
    None: (),
    Open: (),
    Finished: ()
}

#[derive(Model, Copy, Drop, Serde, SerdeLen)]
struct Game {
    #[key]
    x: u64,
    #[key]
    y: u64,
    id: u32,
    creator: ContractAddress,
    state: State,
    size: u64,
    mines_amount: u64,
    started_timestamp: u64
}  

Import them

Don't forget to import them.

use super::{Game, State};
use super::{APP_KEY, APP_ICON, APP_MANIFEST, GAME_MAX_DURATION};

Set up functions

In ActionsImpl, please declare functions.

#[dojo::contract]
mod minesweeper_actions {
    /// ...
    use poseidon::poseidon_hash_span;
    #[derive(Drop, starknet::Event)]
    struct GameOpened {
        game_id: u32,
        creator: ContractAddress
    }

    #[event]
    #[derive(Drop, starknet::Event)]
    enum Event {
        GameOpened: GameOpened
    }
    /// ...
    #[external(v0)]
    impl ActionsImpl of IMinesweeperActions<ContractState> {
        fn init(self: @TContractState) {}
        fn interact(self: @TContractState, default_params: DefaultParameters, size: u64, mines_amount: u64) {}
        fn reveal(self: @TContractState, default_params: DefaultParameters) {}
        fn explode(self: @TContractState, default_params: DefaultParameters) {}
        fn ownerless_space(self: @TContractState, default_params: DefaultParameters, size: u64) -> bool {}
    }
}