// API client — replaces the sql.js database layer.
// Swap these fetch() calls for any other transport when needed.

const BASE = '/api';

async function api(path, options = {}) {
  const res = await fetch(BASE + path, options);
  if (res.status === 204) return null;
  return res.json().then(data => ({ ok: res.ok, status: res.status, data }));
}

// ── Queries ───────────────────────────────────────────────────────────────────

async function getInstances(filters = {}) {
  const params = new URLSearchParams(
    Object.entries(filters).filter(([, v]) => v)
  );
  const res = await fetch(`${BASE}/instances?${params}`);
  return res.json();
}

async function getInstance(vmid) {
  const res = await fetch(`${BASE}/instances/${vmid}`);
  if (res.status === 404) return null;
  return res.json();
}

async function getDistinctStacks() {
  const res = await fetch(`${BASE}/instances/stacks`);
  return res.json();
}

// ── Mutations ─────────────────────────────────────────────────────────────────

async function createInstance(data) {
  const { ok, data: body } = await api('/instances', {
    method: 'POST',
    headers: { 'Content-Type': 'application/json' },
    body: JSON.stringify(data),
  });
  if (!ok) return { ok: false, error: body.error ?? body.errors?.[0] ?? 'error creating instance' };
  return { ok: true };
}

async function updateInstance(vmid, data) {
  const { ok, data: body } = await api(`/instances/${vmid}`, {
    method: 'PUT',
    headers: { 'Content-Type': 'application/json' },
    body: JSON.stringify(data),
  });
  if (!ok) return { ok: false, error: body.error ?? body.errors?.[0] ?? 'error updating instance' };
  return { ok: true };
}

async function deleteInstance(vmid) {
  await api(`/instances/${vmid}`, { method: 'DELETE' });
}

async function getInstanceHistory(vmid) {
  const res = await fetch(`${BASE}/instances/${vmid}/history`);
  return res.json();
}