1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
|
import { h, createContext } from 'preact';
import { useRef, useState, useCallback, useEffect, useContext } from 'preact/hooks';
import { API_PREFIX } from './config';
const fetchJSON = async (url, method='GET', data=undefined) => {
const res = await fetch(API_PREFIX + url, {
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 initialState = { user: null, discussions: [] };
const reducer = async (action, ref) => {
switch (action.type) {
case 'login': {
const { username, password } = action;
await fetchJSON('/discdag/login', 'POST', { username, password });
return await reducer({ type: 'refresh' }, ref);
}
case 'logout': {
await fetchJSON('/discdag/logout', 'POST');
return await reducer({ type: 'refresh' }, ref);
}
case 'refresh': {
const { user, discussions } = await fetchJSON('/discdag/list');
return { ...ref.current, user, discussions };
}
default:
throw new Error('Unexpected action');
}
};
const UserContext = createContext({
state: initialState,
dispatch: () => {
throw new Error("no UserContext Provider!");
},
});
export const UserContainer = ({ children }) => {
const ref = useRef();
const [state, setState] = useState(initialState);
ref.current = state;
const dispatch = useCallback(async (action) => {
const nextState = await reducer(action, ref);
setState(nextState);
}, [ref]);
useEffect(() => dispatch({ type: 'refresh' }), []);
return (
<UserContext.Provider value={{ state, dispatch }}>
{children}
</UserContext.Provider>
);
};
export const useUser = () => useContext(UserContext).state;
export const useDispatch = () => useContext(UserContext).dispatch;
export const useUserCtx = () => useContext(UserContext);
|
