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import { h, createContext } from 'preact';
import { useRef, useState, useCallback, useContext } from 'preact/hooks';
import { API_PREFIX } from './config';
export const fetchJSON = async (url, method='GET', data=undefined) => {
const res = await fetch(new URL(url, API_PREFIX).href, {
method,
credentials: 'include',
headers: { 'content-type': data && 'application/json' },
body: data && JSON.stringify(data),
});
if (res.status !== 200)
throw new Error("wrong status");
return res.json();
};
const DispatchContext = createContext((action) => {
throw new Error(`Unhandled action: ${action.type}`);
});
export const useDispatcher = ({ reducer, initialState }) => {
const parentDispatch = useDispatch();
const ref = useRef();
const [state, setState] = useState(initialState);
ref.current = state;
const dispatch = useCallback((action) => {
const update = reducer(action);
if (!update) return parentDispatch(action);
return update.then(f => setState(f(ref.current)));
}, [ref, reducer]);
return {
state,
dispatch,
DispatchProvider: ({ children }) => <DispatchContext.Provider value={dispatch} children={children} />,
};
};
export const useDispatch = () => useContext(DispatchContext);
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