import type { CarePlan } from 'fhir/r4';

/** The parts of a care plan its edit form writes; a field it leaves out was cleared there. */
const FORM_FIELDS = [
    'status', 'intent', 'text', 'category', 'encounter', 'basedOn', 'replaces', 'partOf', 'title', 'description',
    'created', 'note', 'contributor', 'careTeam', 'addresses', 'goal', 'activity', 'period',
] as const;

/**
 * A form's save written onto the plan it opened: the form's own fields as edited (cleared ones removed), and every
 * other field - author, identifier, instantiation, supporting information, extensions - kept as stored.
 */
export const onTheOpenedPlan = (opened: CarePlan | undefined, edited: CarePlan): CarePlan => {
    if (!opened) return edited;
    const kept: CarePlan = { ...opened };
    FORM_FIELDS.forEach((field) => { delete kept[field]; });
    return {
        ...kept,
        ...edited,
        meta: { ...opened.meta, ...edited.meta },
        ...(edited.author ? {} : opened.author ? { author: opened.author } : {}),
        ...(edited.subject ? {} : opened.subject ? { subject: opened.subject } : {}),
    };
};