// ===============================
// state.js — Stato condiviso + API
// ===============================

let localPhotos = [];
let photoDB = [];

// ---- LAST SYNC ----
function getLastSync() {
  return localStorage.getItem("lastSync");
}

function setLastSync(ts) {
  if (!ts) return;
  localStorage.setItem("lastSync", ts);
}

// ---- STATO FOTO ----
function getLocalPhotos() {
  return localPhotos;
}

function setLocalPhotos(photos) {
  localPhotos = Array.isArray(photos) ? photos : [];
  photoDB = [...localPhotos];
}

function addPhotoLocal(photo) {
  if (!photo || !photo.id) return;
  const idx = localPhotos.findIndex(p => p.id === photo.id);
  if (idx >= 0) localPhotos[idx] = photo;
  else localPhotos.push(photo);
}

function removePhotoLocal(id) {
  const before = localPhotos.length;
  localPhotos = localPhotos.filter(p => p.id !== id);
  const after = localPhotos.length;
  console.log("[removePhotoLocal] id:", id, "prima:", before, "dopo:", after);
}

function saveLocalState() {
  try {
    localStorage.setItem("photosCache", JSON.stringify(localPhotos));
  } catch (e) {
    console.warn("saveLocalState error:", e);
  }
}

// ---- API ----

async function getAllPhotos() {
  const token = localStorage.getItem("token");

  console.log("[getAllPhotos] Fetch /photos...");
  const res = await fetch("/photos", {
    headers: {
      "Authorization": "Bearer " + token
    }
  });

  if (!res.ok) throw new Error("Errore getAllPhotos");

  const data = await res.json();
  const photos = data.photos || data || [];
  console.log("[getAllPhotos] numero foto:", photos.length);

  setLocalPhotos(photos);
  return photos;
}

async function getPhotoById(id) {
  const token = localStorage.getItem("token");

  const q = `id=${encodeURIComponent(id)}`;
  const res = await fetch(`/photos/byIds?${q}`, {
    headers: {
      "Authorization": "Bearer " + token
    }
  });

  if (!res.ok) throw new Error("Errore getPhotoById");

  const data = await res.json();
  return data.photos || [];
}


async function getChanges(since, user) {
  const token = localStorage.getItem("token");

  const url = `/photos/changes?since=${encodeURIComponent(since)}&user=${encodeURIComponent(user)}`;
  console.log("[getChanges] URL:", url);

  const res = await fetch(url, {
    headers: {
      "Authorization": "Bearer " + token
    }
  });

  if (!res.ok) throw new Error("Errore getChanges");
  return await res.json();
}


// ---- EXPORT ----
window.getLastSync = getLastSync;
window.setLastSync = setLastSync;
window.getLocalPhotos = getLocalPhotos;
window.setLocalPhotos = setLocalPhotos;
window.addPhotoLocal = addPhotoLocal;
window.removePhotoLocal = removePhotoLocal;
window.saveLocalState = saveLocalState;
window.getAllPhotos = getAllPhotos;
window.getPhotoById = getPhotoById;
window.getChanges = getChanges;