// db/dbWs.js
console.log(">>> dbWs.js CARICATO:", __filename);
const knex = require("./knex");

// ===============================
// SESSIONI
// ===============================

async function upsertSession(session_id, user, device_id) {
  const now = Date.now();
  const existing = await knex("ws_sessions")
    .where({ session_id, device_id })
    .first();

  if (!existing) {
    await knex("ws_sessions").insert({
      session_id,
      user,
      device_id,
      connected_at: now,
      last_ack: now,
      last_sync: null,
      need_full_sync: false
    });
  } else {
    await knex("ws_sessions")
      .where({ session_id, device_id })
      .update({
        user,
        connected_at: now,
        last_ack: now
      });
  }
}

async function getDevicesForSession(session_id) {
  const rows = await knex('ws_sessions')
    .where({ session_id })
    .select('device_id');

  return rows.map(r => r.device_id);
}

async function getSession(session_id, device_id) {
  return knex("ws_sessions")
    .where({ session_id, device_id })
    .first();
}

async function updateSessionAck(session_id, device_id) {
  return knex("ws_sessions")
    .where({ session_id, device_id })
    .update({ last_ack: Date.now() });
}

async function setSessionNeedFullSync(session_id, device_id, value) {
  return knex("ws_sessions")
    .where({ session_id, device_id })
    .update({ need_full_sync: value });
}

async function clearNeedFullSync(session_id, device_id) {
  return knex("ws_sessions")
    .where({ session_id, device_id })
    .update({ need_full_sync: false });
}

async function getSessionsByUser(user) {
  return knex("ws_sessions").where({ user });
}

async function deleteSession(session_id, device_id) {
  await knex("ws_sessions").where({ session_id, device_id }).del();
  await knex("pending_events").where({ session_id, device_id }).del();
}

// ===============================
// PENDING EVENTS (nuovo modello)
// ===============================

async function insertPendingEvent({ user_id, session_id, device_id, event_id, payload, created_at }) {
  return knex("pending_events").insert({
    user_id,
    session_id,
    device_id,
    event_id,
    payload,
    created_at
  });
}

async function deletePendingEvent({ user_id, session_id, device_id, event_id }) {
  return knex("pending_events")
    .where({ user_id, session_id, device_id, event_id })
    .delete();
}

async function getPendingEvents(user_id, session_id, device_id) {
  return knex("pending_events")
    .where({ user_id, session_id, device_id })
    .orderBy("created_at", "asc");
}

async function deleteAllSessions() {
  console.log(">>> deleteAllSessions() – elimino tutte le sessioni WS");
  return knex("ws_sessions").del();
}

async function deleteAllPendingEvents() {
  console.log(">>> deleteAllPendingEvents() – elimino tutti i pending events");
  return knex("pending_events").del();
}

async function setLastSync(session_id, device_id, timestamp = null) {
  const ts = timestamp || Date.now();
  return knex("ws_sessions")
    .where({ session_id, device_id })
    .update({ last_sync: ts });
}

// ===============================
// EXPORT
// ===============================

module.exports = {
  upsertSession,
  getSession,
  updateSessionAck,
  setSessionNeedFullSync,
  clearNeedFullSync,
  deleteSession,
  getSessionsByUser,

  insertPendingEvent,
  deletePendingEvent,
  getPendingEvents,
  getDevicesForSession,

  setLastSync,
  deleteAllSessions,
  deleteAllPendingEvents
};