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

/** What an unnamed custom task is called, on create and on edit alike. */
export const customTaskCodeText = (title?: string): string => title?.trim() || 'Custom task';

export interface CustomTaskEdit {
    title?: string;
    instructions: string;
    priority?: Task['priority'];
    extension: Task['extension'];
    basedOn?: Task['basedOn'];
    restriction?: Task['restriction'];
    lastModified: string;
}

// The stored task with the edit applied; its identity, patient and codings stay as they were.
export const applyCustomTaskEdit = (task: Task, edit: CustomTaskEdit): Task => ({
    ...task,
    code: { ...task.code, text: customTaskCodeText(edit.title) },
    description: edit.instructions.trim(),
    priority: edit.priority ?? task.priority,
    extension: edit.extension,
    basedOn: edit.basedOn,
    focus: task.focus?.reference?.startsWith('Appointment/') ? undefined : task.focus,
    restriction: edit.restriction,
    lastModified: edit.lastModified,
});