/* Usage analytics core — the ONE implementation (D5 / T7.10).

   This existed three times: the creator's copy, the wizard's copy (which had no
   caller — the button lived on the creator), and the admin console's own reader.
   Once the creator stopped being an iframe (B7/T7.1) the first two sat in one
   document as five colliding globals; an unreferenced duplicate is exactly what
   produced D5. One core now; the pages keep only a thin track() wrapper because
   page state (the creator's dev-mode pause) belongs to the page.

   The storage KEYS are unchanged on purpose: everything recorded before this
   file existed is still readable through it. No field VALUES are ever stored —
   a field-edit event records the field id, nothing else.

   Classic script, no modules: exposes window.WPUsage. */
'use strict';

(function () {
  var SESSION = 's_' + Date.now().toString(36) + Math.random().toString(36).slice(2, 6);

  function load(key) {
    try { return JSON.parse(localStorage.getItem(key)) || { events: [] }; }
    catch (e) { return { events: [] }; }
  }

  function save(key, data) {
    try { localStorage.setItem(key, JSON.stringify(data)); }
    catch (e) { /* storage unavailable — degrade silently */ }
  }

  function track(key, event, detail) {
    try {
      var d = load(key);
      d.events.push({ ts: new Date().toISOString(), session: SESSION, event: event, detail: detail || null });
      if (d.events.length > 5000) d.events = d.events.slice(-5000);
      save(key, d);
    } catch (e) { /* never let telemetry break the tool it watches */ }
  }

  function download(key, prefix) {
    var blob = new Blob([JSON.stringify(load(key), null, 2)], { type: 'application/json' });
    var a = document.createElement('a');
    a.href = URL.createObjectURL(blob);
    a.download = (prefix || 'wp-usage') + '-' + new Date().toISOString().slice(0, 10) + '.json';
    document.body.appendChild(a);
    a.click();
    a.remove();
    setTimeout(function () { URL.revokeObjectURL(a.href); }, 1000);
  }

  window.WPUsage = {
    load: load,
    save: save,
    track: track,
    download: download,
    // The pre-D5 keys, verbatim — continuity of the recorded data is a done-when.
    KEYS: { creator: 'wp_iwp_analytics_v1', wizard: 'wp_suite_analytics_v1' },
  };
})();