// Kinds of food: a library of user-named labels a meal can carry. The rules
// worth holding still are the ones that decide what happens to people who
// never use the feature, and what happens to history when a kind is deleted.
import { load } from "./extract.mjs";
import { suite, eq, ok, report } from "./assert.mjs";

let store = [];
let synced = 0, rendered = 0;
let nextId = 0;

const app = load({
  names: [
    "NO_KIND", "FOOD_COLORS",
    "loadFoodKinds", "saveFoodKinds", "liveFoodKinds",
    "addFoodKind", "updateFoodKind", "deleteFoodKind",
    "setDefaultFoodKind", "defaultFoodKindId", "foodKindNames",
  ],
  stubs: {
    foodKindsKey: () => "k",
    localStorage: {
      getItem: () => JSON.stringify(store),
      setItem: (_, v) => { store = JSON.parse(v); },
    },
    uuid: () => `id${++nextId}`,
    scheduleSync: () => { synced++; },
    render: () => { rendered++; },
  },
});

const reset = () => { store = []; nextId = 0; };
const names = () => app.liveFoodKinds().map(k => k.name);

suite("an account with no kinds behaves as it always did");
{
  reset();
  eq(app.liveFoodKinds(), [], "no kinds to begin with");
  eq(app.defaultFoodKindId(), app.NO_KIND, "…so a new meal starts with no kind");
  eq(app.NO_KIND, "", "and 'no kind' is the empty string, which is what old meals carry");
}

suite("creating kinds");
{
  reset();
  const dry = app.addFoodKind("Dry");
  const fresh = app.addFoodKind("Fresh");
  eq(names(), ["Dry", "Fresh"], "listed in creation order, not alphabetical");
  eq([dry.colorIndex, fresh.colorIndex], [0, 1], "each takes the next palette slot");
  ok(synced > 0, "a new kind is queued for sync");
}

suite("the default");
{
  reset();
  const dry = app.addFoodKind("Dry");
  const fresh = app.addFoodKind("Fresh");
  eq(app.defaultFoodKindId(), app.NO_KIND, "nothing is default until you say so");

  app.setDefaultFoodKind(dry.id);
  eq(app.defaultFoodKindId(), dry.id, "the chosen kind becomes the default");

  app.setDefaultFoodKind(fresh.id);
  eq(app.defaultFoodKindId(), fresh.id, "choosing another moves it");
  eq(app.liveFoodKinds().filter(k => k.isDefault).length, 1,
     "…and unflags the old one, so there is never more than one");

  app.setDefaultFoodKind(app.NO_KIND);
  eq(app.defaultFoodKindId(), app.NO_KIND, "and it can be cleared back to no kind");
}

suite("two devices that each set a default");
{
  // What a sync race leaves behind: both rows flagged, different timestamps.
  // Resolving to the newer beats showing two defaults or picking at random.
  reset();
  store = [
    { id: "a", name: "Dry", colorIndex: 0, isDefault: true, updatedAt: 1000 },
    { id: "b", name: "Fresh", colorIndex: 1, isDefault: true, updatedAt: 2000 },
  ];
  eq(app.defaultFoodKindId(), "b", "the more recent flag wins");
}

suite("renaming and deleting keep history readable");
{
  reset();
  const dry = app.addFoodKind("Dry");
  app.updateFoodKind(dry.id, { name: "Dry kibble" });
  eq(names(), ["Dry kibble"], "renaming changes the name in place");
  eq(app.foodKindNames().get(dry.id), "Dry kibble",
     "…and meals pointing at the id follow it, since they resolve by id");

  app.deleteFoodKind(dry.id);
  eq(names(), [], "a deleted kind leaves the picker");
  eq(app.foodKindNames().get(dry.id), "Dry kibble",
     "…but its name still resolves, so meals logged as it stay readable");
}

suite("colours survive a deletion");
{
  // Deriving colour from position in the live list would repaint every past
  // chart the moment a kind was removed. The index is fixed at creation.
  reset();
  app.addFoodKind("Dry");
  const fresh = app.addFoodKind("Fresh");
  const raw = app.addFoodKind("Raw");
  eq(raw.colorIndex, 2, "the third kind takes the third slot");

  app.deleteFoodKind(fresh.id);
  const live = app.liveFoodKinds();
  eq(live.map(k => k.colorIndex), [0, 2],
     "deleting the middle kind leaves the others' colours alone");
  eq(app.addFoodKind("Treats").colorIndex, 3,
     "and the next kind does not reuse the freed slot");
}

suite("the palette wraps rather than running out");
{
  reset();
  for (let i = 0; i < app.FOOD_COLORS + 2; i++) app.addFoodKind(`K${i}`);
  const live = app.liveFoodKinds();
  eq(live.length, app.FOOD_COLORS + 2, "you can have more kinds than colours");
  eq(live[app.FOOD_COLORS].colorIndex % app.FOOD_COLORS, 0,
     "…and the palette wraps, so two share rather than one having none");
}

// ---------------------------------------------- the day's split in the Meals tile
// The tile holds the day's total; this puts the per-kind figures under it, so
// the parts and the sum they make are read in one place. The case that matters
// is the one where none of it should appear.
{
  let kinds = [];
  let kindsEl, gramsEl;
  const view = load({
    names: ["NO_KIND", "renderDayFoodKinds"],
    stubs: {
      document: {
        getElementById: () => kindsEl,
        createElement: () => ({ textContent: "", appendChild() {} }),
      },
      liveFoodKinds: () => kinds,
      foodKindNames: () => new Map(kinds.map(k => [k.id, k.name])),
    },
  });
  const meal = (grams, foodKindId = "") => ({ type: "eat", grams, foodKindId });
  const show = (evs) => {
    const lines = [];
    kindsEl = {
      hidden: false, textContent: "",
      appendChild: (n) => lines.push(n.textContent),
    };
    gramsEl = { textContent: "" };
    const total = evs.filter(e => e.type === "eat" && e.grams > 0)
      .reduce((s, e) => s + e.grams, 0);
    view.renderDayFoodKinds(evs, gramsEl, total);
    return { lines, grams: gramsEl.textContent, hidden: kindsEl.hidden };
  };

  suite("the day's food in the Meals tile");
  {
    kinds = [];
    const plain = show([meal(180), meal(120)]);
    eq(plain.hidden, true, "meals with no kind add nothing under the total");
    eq(plain.grams, "", "…and leave the tile's own total line alone");
    eq(show([]).hidden, true, "a day with no meals adds nothing");

    kinds = [{ id: "d", name: "Dry" }];
    const one = show([meal(300, "d"), meal(240, "d")]);
    eq(one.hidden, true, "one kind adds no lines — it would only repeat the total");
    eq(one.grams, "540 g · Dry", "…the total carries its name instead");

    kinds = [{ id: "d", name: "Dry" }, { id: "f", name: "Fresh" }];
    const two = show([meal(200, "d"), meal(100, "f"), meal(60, "d")]);
    eq(two.hidden, false, "two kinds do get their own lines");
    eq(two.lines, ["Dry 260 g", "Fresh 100 g"], "…summed per kind, in the chart's order");

    eq(show([meal(200, "d"), meal(50)]).lines, ["Dry 200 g", "No kind 50 g"],
       "unlabelled food alongside a kind is named, not dropped");

    kinds = [];
    eq(show([meal(90, "gone")]).grams, "90 g · Deleted kind",
       "a kind deleted since still labels its food rather than vanishing");

    kinds = [{ id: "d", name: "Dry" }];
    eq(show([meal(0, "d"), meal(120, "d")]).grams, "120 g · Dry",
       "a meal logged without an amount adds nothing to the split");
  }
}

export default report("food-kinds");