documenso/packages/ui/primitives/form/form.tsx

import * as React from 'react';

import { useLingui } from '@lingui/react';
import type * as LabelPrimitive from '@radix-ui/react-label';
import { Slot } from '@radix-ui/react-slot';
import { AnimatePresence, motion } from 'framer-motion';
import type { ControllerProps, FieldPath, FieldValues } from 'react-hook-form';
import { Controller, FormProvider, useFormContext } from 'react-hook-form';

import { cn } from '../../lib/utils';
import { Label } from '../label';

const Form = FormProvider;

type FormFieldContextValue<
  TFieldValues extends FieldValues = FieldValues,
  TName extends FieldPath<TFieldValues> = FieldPath<TFieldValues>,
> = {
  name: TName;
};

// eslint-disable-next-line @typescript-eslint/consistent-type-assertions
const FormFieldContext = React.createContext<FormFieldContextValue>({} as FormFieldContextValue);

const FormField = <
  TFieldValues extends FieldValues = FieldValues,
  TName extends FieldPath<TFieldValues> = FieldPath<TFieldValues>,
>({
  ...props
}: ControllerProps<TFieldValues, TName>) => {
  return (
    <FormFieldContext.Provider value={{ name: props.name }}>
      <Controller {...props} />
    </FormFieldContext.Provider>
  );
};

const useFormField = () => {
  const fieldContext = React.useContext(FormFieldContext);
  const itemContext = React.useContext(FormItemContext);
  const { getFieldState, formState } = useFormContext();

  const fieldState = getFieldState(fieldContext.name, formState);

  if (!fieldContext) {
    throw new Error('useFormField should be used within <FormField>');
  }

  const { id } = itemContext;

  return {
    id,
    name: fieldContext.name,
    formItemId: `${id}-form-item`,
    formDescriptionId: `${id}-form-item-description`,
    formMessageId: `${id}-form-item-message`,
    ...fieldState,
  };
};

type FormItemContextValue = {
  id: string;
};

// eslint-disable-next-line @typescript-eslint/consistent-type-assertions
const FormItemContext = React.createContext<FormItemContextValue>({} as FormItemContextValue);

const FormItem = React.forwardRef<HTMLDivElement, React.HTMLAttributes<HTMLDivElement>>(
  ({ className, ...props }, ref) => {
    const id = React.useId();

    return (
      <FormItemContext.Provider value={{ id }}>
        <div ref={ref} className={cn('space-y-2', className)} {...props} />
      </FormItemContext.Provider>
    );
  },
);
FormItem.displayName = 'FormItem';

const FormLabel = React.forwardRef<
  React.ElementRef<typeof LabelPrimitive.Root>,
  React.ComponentPropsWithoutRef<typeof LabelPrimitive.Root> & { required?: boolean }
>(({ className, ...props }, ref) => {
  const { formItemId } = useFormField();

  return (
    <Label
      ref={ref}
      className={cn(
        className,
        // error && 'text-destructive', // Uncomment to apply styling on error.
      )}
      htmlFor={formItemId}
      {...props}
    />
  );
});
FormLabel.displayName = 'FormLabel';

const FormControl = React.forwardRef<
  React.ElementRef<typeof Slot>,
  React.ComponentPropsWithoutRef<typeof Slot>
>(({ ...props }, ref) => {
  const { error, formItemId, formDescriptionId, formMessageId } = useFormField();

  return (
    <Slot
      ref={ref}
      id={formItemId}
      aria-describedby={!error ? `${formDescriptionId}` : `${formDescriptionId} ${formMessageId}`}
      aria-invalid={!!error}
      {...props}
    />
  );
});
FormControl.displayName = 'FormControl';

const FormDescription = React.forwardRef<
  HTMLParagraphElement,
  React.HTMLAttributes<HTMLParagraphElement>
>(({ className, ...props }, ref) => {
  const { formDescriptionId } = useFormField();

  return (
    <p
      ref={ref}
      id={formDescriptionId}
      className={cn('text-muted-foreground text-sm', className)}
      {...props}
    />
  );
});
FormDescription.displayName = 'FormDescription';

const FormMessage = React.forwardRef<
  HTMLParagraphElement,
  React.HTMLAttributes<HTMLParagraphElement>
>(({ className, children, ...props }, ref) => {
  const { i18n } = useLingui();

  const { error, formMessageId } = useFormField();

  let body = error ? String(error?.message) : children;

  if (!body) {
    return null;
  }

  // Checks to see if there's a translation for the string, since we're passing IDs for Zod errors.
  if (typeof body === 'string' && i18n.t(body)) {
    body = i18n.t(body);
  }

  return (
    <AnimatePresence>
      <motion.div
        initial={{
          opacity: 0,
          y: -10,
        }}
        animate={{
          opacity: 1,
          y: 0,
        }}
        exit={{
          opacity: 0,
          y: 10,
        }}
      >
        <p
          ref={ref}
          id={formMessageId}
          className={cn('text-xs text-red-500', className)}
          {...props}
        >
          {body}
        </p>
      </motion.div>
    </AnimatePresence>
  );
});
FormMessage.displayName = 'FormMessage';

export {
  useFormField,
  Form,
  FormItem,
  FormLabel,
  FormControl,
  FormDescription,
  FormMessage,
  FormField,
};