// Convert between the board's URL query and a NoteFacets object. The URL query IS the
// filter state (so a lens is shareable/bookmarkable and a saved view is just a link).
import type { LocationQuery, LocationQueryRaw } from "vue-router";
import type { NoteFacets } from "../stores/notes";

function one(v: LocationQuery[string]): string | undefined {
  return (Array.isArray(v) ? v[0] : v) ?? undefined;
}

export function facetsFromQuery(q: LocationQuery): NoteFacets {
  const rawLabel = q.label;
  const labels = (Array.isArray(rawLabel) ? rawLabel : [rawLabel]).filter(
    (x): x is string => typeof x === "string" && x.length > 0,
  );
  const f: NoteFacets = {};
  const text = one(q.q);
  if (text) f.q = text;
  const color = one(q.color);
  if (color) f.color = color;
  if (labels.length) f.label = labels;
  if (one(q.has_reminder) === "true") f.has_reminder = true;
  if (one(q.has_attachment) === "true") f.has_attachment = true;
  const after = one(q.created_after);
  if (after) f.created_after = after;
  const before = one(q.created_before);
  if (before) f.created_before = before;
  return f;
}

export function facetsToQuery(f: NoteFacets): LocationQueryRaw {
  const q: LocationQueryRaw = {};
  if (f.q) q.q = f.q;
  if (f.color) q.color = f.color;
  if (f.label?.length) q.label = f.label;
  if (f.has_reminder) q.has_reminder = "true";
  if (f.has_attachment) q.has_attachment = "true";
  if (f.created_after) q.created_after = f.created_after;
  if (f.created_before) q.created_before = f.created_before;
  return q;
}

// How many facets are active (labels counted individually) — drives the "Filters (N)" badge.
export function facetCount(f: NoteFacets): number {
  let n = 0;
  if (f.q) n++;
  if (f.color) n++;
  n += f.label?.length ?? 0;
  if (f.has_reminder) n++;
  if (f.has_attachment) n++;
  if (f.created_after || f.created_before) n++;
  return n;
}