import { i18n, t, type Key } from './i18n/index.svelte';
import type { Inertia, Proposal, Unit } from './types';

/** « 3 / 5 · moyenne ». */
export function inertiaLevel(k: Inertia): string {
  return t('inertia.level', { k, name: t(`inertia.name.${k}`) });
}

/** « inertie 3 / 5 · moyenne ». */
export function inertiaBadge(k: Inertia): string {
  return t('inertia.badge', { level: inertiaLevel(k) });
}

const SECTIONS = ['introduction', 'fondamental', 'technique', 'conclusion', 'annexe', 'formule', 'inertie', 'ordonnancement'];

/** The name of a section of the seed, or null. */
export function sectionLabel(s: string | null | undefined): string | null {
  return s && SECTIONS.includes(s) ? t(`section.${s}` as Key) : null;
}

/** The name of a module (ADR 0009): « Titre du document », « Ordre des articles · Conclusion ». */
export function moduleName(unit: Unit): string {
  if (unit.kind === 'title') return t('module.title.name');
  const section = sectionLabel(unit.section) ?? unit.section;
  return section ? t('module.order.named', { section }) : t('module.order.name');
}

/** What a proposal is, in words, whatever its kind. */
export function titleOf(p: Proposal, unit: Unit | undefined): string {
  if (p.kind === 'inertia' && p.inertiaTarget) {
    return t('deep.inertia', { level: inertiaLevel(p.inertiaTarget) });
  }
  if (p.kind === 'remove') return t('deep.removal', { title: unit?.inForce?.title ?? p.title });
  if (p.kind === 'order') return unit ? moduleName(unit) : t('module.order.name');
  return p.title;
}

/** Its relation to the text in force. */
export function relationOf(p: Proposal, unit: Unit | undefined): string {
  if (p.kind !== 'text' && p.kind !== 'title') return '';
  if (unit?.inForce && unit.inForce.id !== p.id) return t('deep.rival', { title: unit.inForce.title });
  return '';
}

/** What an order version says of itself: completed at the end, or the order in force already. */
export function orderNote(p: Proposal): string[] {
  const o = p.order;
  if (!o || p.status === 'in_force') return [];
  const notes: string[] = [];
  if (o.added.length) notes.push(i18n.plural('module.order.added', o.added.length));
  if (o.dropped.length) notes.push(i18n.plural('module.order.dropped', o.dropped.length));
  if (o.same) notes.push(t('module.order.same'));
  return notes;
}