// Tab lifecycle: clean up swarms and subscriptions when tabs close.
// Depends on: state.js (tabSwarms, swarmRefCount), logs.js (log), native-messaging.js (send, subscribedTabs, dashboardTabs)

browser.tabs.onRemoved.addListener((tabId) => {
  log('Tab closed:', tabId);
  const swarmIds = tabSwarms.get(tabId);
  if (swarmIds) {
    for (const swarmId of swarmIds) {
      const count = (swarmRefCount.get(swarmId) || 0) - 1;
      swarmRefCount.set(swarmId, count);
      log('Swarm', swarmId, 'refcount now:', count);
      if (count <= 0) {
        log('Last tab for swarm', swarmId, '- destroying');
        send({ type: 'destroy', payload: { swarmId } }).catch(() => {});
        swarmRefCount.delete(swarmId);
      }
    }
    tabSwarms.delete(tabId);
  }
  subscribedTabs.delete(tabId);
  dashboardTabs.delete(tabId);
});

// Clean up subscription Sets when a tab navigates away. Without this, a tab
// that subscribes and then navigates to a non-extension page stays in the Sets
// until it is closed, causing silent sendMessage failures on every broadcast.
browser.tabs.onUpdated.addListener((tabId, changeInfo) => {
  if (changeInfo.url) {
    subscribedTabs.delete(tabId);
    dashboardTabs.delete(tabId);
  }
});