states.ts

import { createAction, getType, ActionType } from "typesafe-actions";
import { runSaga, stdChannel } from "redux-saga";
import { fork, put, takeEvery, select } from "redux-saga/effects";

const setWalletAttribute = createAction("STATE/SET_WALLET_ATTRIBUTE",
    (address: string, attr: string, value: any) => ({ address, attr, value }),
)();

type StateAction = ActionType<typeof setWalletAttribute>;

class State {
    private readonly walletAttributes: Map<string, any>;

    public constructor() {
        this.walletAttributes = new Map<string, any>();
    }

    public handle(action: StateAction) {
        switch (action.type) {
            case getType(setWalletAttribute): {
                const { address, attr, value } = action.payload;
                this.walletAttributes.set(`${address}.${attr}`, value);
                break;
            }
        }
    }

    public getWalletAttribute(address: string, attr: string): any {
        return this.walletAttributes.get(`${address}.${attr}`);
    }
}

const channel = stdChannel();
const state = new State();
const store = {
    channel,

    dispatch(action) {
        state.handle(action);
        channel.put(action);
    },

    getState() {
        return state;
    }
};

const getWalletBalance = (state: State, address: string): number => {
    return state.getWalletAttribute(address, "balance");
};

const addWalletBalance = createAction("WALLET/ADD_BALANCE",
    (address: string, amount: number) => ({ address, amount }),
)();

function * handleAddWalletBalance() {
    yield takeEvery(addWalletBalance, function * (action: ReturnType<typeof addWalletBalance>) {
        const { address, amount } = action.payload;
        const balance = yield select(getWalletBalance, address);
        yield put(setWalletAttribute(address, "balance", amount + (balance || 0)));
    });
}


function * rootSaga() {
    yield fork(handleAddWalletBalance);
    for (let i = 1; i <= 100; i++) {
        yield put(addWalletBalance("wallet1", i));
    }
}

runSaga(store, rootSaga);
console.log("wallet1 balance", getWalletBalance(store.getState(), "wallet1"));