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
|
import { AbsoluteTime, TranslatedString } from "@gnu-taler/taler-util";
import { ComponentChildren, VNode, createContext, h } from "preact";
import { MutableRef, StateUpdater, useEffect, useRef } from "preact/hooks";
export interface FormType<T> {
value: MutableRef<Partial<T>>;
initialValue?: Partial<T>;
onUpdate?: StateUpdater<T>;
computeFormState?: (v: T) => FormState<T>;
}
//@ts-ignore
export const FormContext = createContext<FormType<any>>({});
export type FormState<T> = {
[field in keyof T]?: T[field] extends AbsoluteTime
? Partial<InputFieldState>
: T[field] extends Array<infer P>
? Partial<InputArrayFieldState<P>>
: T[field] extends object
? FormState<T[field]>
: Partial<InputFieldState>;
};
export interface InputFieldState {
/* should show the error */
error?: TranslatedString;
/* should not allow to edit */
readonly: boolean;
/* should show as disable */
disabled: boolean;
/* should not show */
hidden: boolean;
}
export interface InputArrayFieldState<T> extends InputFieldState {
elements: FormState<T>[];
}
export function FormProvider<T>({
children,
initialValue,
onUpdate,
computeFormState,
}: {
initialValue?: Partial<T>;
onUpdate?: (v: Partial<T>) => void;
computeFormState?: (v: T) => FormState<T>;
children: ComponentChildren;
}): VNode {
const value = useRef(initialValue ?? {});
useEffect(() => {
return function onUnload() {
value.current = initialValue ?? {};
};
});
return (
<FormContext.Provider
value={{ initialValue, value, onUpdate, computeFormState }}
>
<form>{children}</form>
</FormContext.Provider>
);
}
|
