waveterm/frontend/app/shadcn/form.tsx

// Copyright 2025, Command Line Inc.
// SPDX-License-Identifier: Apache-2.0
//
// This file is based on components from shadcn/ui, which is licensed under the MIT License.
// Original source: https://github.com/shadcn/ui
// Modifications made by Command Line Inc.

"use client";

import * as LabelPrimitive from "@radix-ui/react-label";
import { Slot } from "@radix-ui/react-slot";
import { Controller, ControllerProps, FieldPath, FieldValues, FormProvider, useFormContext } from "react-hook-form";

import { Label } from "@/shadcn/label";
import * as React from "react";

import { cn } from "@/shadcn/lib/utils";

const Form = FormProvider;

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

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;
};

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>
>(({ className, ...props }, ref) => {
    const { error, formItemId } = useFormField();

    return <Label ref={ref} className={cn(error && "text-destructive", className)} 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-[0.8rem] text-muted-foreground", className)}
                {...props}
            />
        );
    }
);
FormDescription.displayName = "FormDescription";

const FormMessage = React.forwardRef<HTMLParagraphElement, React.HTMLAttributes<HTMLParagraphElement>>(
    ({ className, children, ...props }, ref) => {
        const { error, formMessageId } = useFormField();
        const body = error ? String(error?.message) : children;

        if (!body) {
            return null;
        }

        return (
            <p
                ref={ref}
                id={formMessageId}
                className={cn("text-[0.8rem] font-medium text-destructive", className)}
                {...props}
            >
                {body}
            </p>
        );
    }
);
FormMessage.displayName = "FormMessage";

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