race_api/
engine.rs

1use borsh::{BorshDeserialize, BorshSerialize};
2
3use crate::{
4    effect::Effect,
5    error::{HandleError, HandleResult},
6    event::Event,
7    prelude::ServerJoin,
8    types::PlayerJoin,
9};
10
11/// A subset of on-chain account, used for game handler
12/// initialization.  The `access_version` may refer to an old state
13/// when the game is started by transactor.
14#[derive(Debug, Clone, BorshSerialize, BorshDeserialize)]
15pub struct InitAccount {
16    pub addr: String,
17    pub players: Vec<PlayerJoin>,
18    pub servers: Vec<ServerJoin>,
19    pub data: Vec<u8>,
20    pub access_version: u64,
21    pub settle_version: u64,
22    pub max_players: u16,
23    pub checkpoint: Vec<u8>,
24}
25
26impl InitAccount {
27    pub fn data<S: BorshDeserialize>(&self) -> Result<S, HandleError> {
28        S::try_from_slice(&self.data).or(Err(HandleError::MalformedGameAccountData))
29    }
30
31    pub fn checkpoint<S: BorshDeserialize>(&self) -> Result<Option<S>, HandleError> {
32        if self.checkpoint.is_empty() {
33            Ok(None)
34        } else {
35            S::try_from_slice(&self.checkpoint).or(Err(HandleError::MalformedCheckpointData)).map(Some)
36        }
37    }
38
39    /// Add a new player.  This function is only available in tests.
40    /// This function will panic when a duplicated position is
41    /// specified.
42    pub fn add_player<S: Into<String>>(
43        &mut self,
44        addr: S,
45        position: usize,
46        balance: u64,
47        verify_key: String,
48    ) {
49        self.access_version += 1;
50        let access_version = self.access_version;
51        if self.players.iter().any(|p| p.position as usize == position) {
52            panic!("Failed to add player, duplicated position");
53        }
54        self.players.push(PlayerJoin {
55            position: position as _,
56            balance,
57            addr: addr.into(),
58            access_version,
59            verify_key,
60        })
61    }
62}
63
64impl Default for InitAccount {
65    fn default() -> Self {
66        Self {
67            addr: "".into(),
68            players: Vec::new(),
69            servers: Vec::new(),
70            data: Vec::new(),
71            access_version: 0,
72            settle_version: 0,
73            max_players: 10,
74            checkpoint: Vec::new(),
75        }
76    }
77}
78
79pub trait GameHandler: Sized + BorshSerialize + BorshDeserialize {
80    type Checkpoint: BorshSerialize + BorshDeserialize;
81
82    /// Initialize handler state with on-chain game account data.
83    fn init_state(effect: &mut Effect, init_account: InitAccount) -> HandleResult<Self>;
84
85    /// Handle event.
86    fn handle_event(&mut self, effect: &mut Effect, event: Event) -> HandleResult<()>;
87
88    /// Create checkpoint from current state.
89    fn into_checkpoint(self) -> HandleResult<Self::Checkpoint>;
90}
race_api/engine.rs

race_api/
engine.rs
