import { Hypermedia, HypermediaAction } from 'first-npm-package-nicule/core';

export function prefixValue(fieldName: string, prefix: string): (hypermediaAction: HypermediaAction, hypermedia: Hypermedia) => HypermediaAction {
    return (hypermediaAction: HypermediaAction) => {
        const { fields: oldFields, ...rest } = hypermediaAction;
        const fields = [];
        oldFields.forEach(({ name, value, ...remainder }) => {
            if (fieldName === name) {
                value = prefix + value;
            }
            fields.push({ name, value, ...remainder });
        });

        return {
            ...rest,
            fields
        };
    };
}