// src/integrations/atlas/devices.js

import { atlasGet } from './client.js';
import { logger } from '../../utils/logger.js';

// In-memory cache (→ replace with node-cache/redis later if scale needed)
let cachedDeviceList = [];          // full list from /organization/devices
let lastCacheTime = 0;
const CACHE_TTL_MS = 60 * 60 * 1000; // 1 hour – adjust based on how often devices change

/**
 * Refresh full organization device list (called by cron)
 * Handles pagination (API defaults to 100 items/page, max per_page=100; uses ?page=N and next_page in body)
 */
export async function refreshAtlasDevicesCache() {
  const start = Date.now();
  logger('atlas:devices', 'Refreshing full device cache', 'debug');

  try {
    let allItems = [];
    let page = 1;
    let hasMore = true;
    const PAGE_SIZE = 100;

    while (hasMore) {
      const data = await atlasGet('/organization/devices', { page, per_page: PAGE_SIZE });
      const items = Array.isArray(data.items) ? data.items : [];
      allItems = allItems.concat(items);

      const nextPage = data.next_page;
      hasMore = !!nextPage && items.length > 0;

      logger('atlas:devices', `Page ${page}: ${items.length} items (running total ${allItems.length}) next_page=${nextPage}`, 'debug');

      if (items.length < PAGE_SIZE) {
        hasMore = false;
      }
      if (hasMore) {
        page = Number(nextPage) || (page + 1);
        await new Promise(r => setTimeout(r, 80)); // be nice between pages
      }
      if (page > 100) { // hard safety
        logger('atlas:devices', 'Safety stop: exceeded 100 pages');
        break;
      }
    }

    cachedDeviceList = allItems;
    lastCacheTime = Date.now();

    logger('atlas:devices', `Cached ${cachedDeviceList.length} devices (${Date.now() - start} ms)`, 'debug');
  } catch (err) {
    logger('atlas:devices', `Cache refresh failed: ${err.message}`);
    // Keep old cache if possible
  }
}

/**
 * Get cached device list (auto-refresh if stale/empty)
 */
export async function getAtlasDeviceList(forceRefresh = false) {
  const now = Date.now();
  if (forceRefresh || !cachedDeviceList.length || (now - lastCacheTime > CACHE_TTL_MS)) {
    await refreshAtlasDevicesCache();
  }
  return cachedDeviceList;
}

/**
 * Find devices matching a store number (name contains 6-digit padded storeNum, e.g. "002477" in "US002477AMP")
 * @param {string|number} storeNumber e.g. "2477", 305 or "000305"
 * @returns {Promise<Array>} matching device summaries (name, id, status, etc.)
 */
export async function findAtlasDevicesForStore(storeNumber) {
  // Always use 6-digit zero-padded form for name matching in Atlas (e.g. 2477 → 002477, 305 → 000305).
  // Raw/short numbers like "305" can substring-match unrelated devices (e.g. "00305x"), causing
  // multiple/incorrect Atlas AMP results. Names follow US00NNNNAMP pattern.
  const padded = String(storeNumber).trim().padStart(6, '0');
  logger('atlas:devices', `Looking up Atlas devices for store ${storeNumber} (padded ${padded})`, 'debug');

  const devices = await getAtlasDeviceList();

  const matches = devices.filter(dev => {
    const name = String(dev.name || '').toUpperCase();
    return name.includes(padded);
  });

  logger('atlas:findDevices', 
    `Searched for store ${padded} → Found ${matches.length} Atlas AMP device(s)`, 'debug');

  if (matches.length > 0) {
    logger('atlas:findDevices', `Matched: ${matches.map(m => m.name).join(', ')}`, 'debug');
  }

  return matches;
}

/**
 * Get detailed info for a single Atlas device by its ID
 * @param {string} deviceId
 * @returns {Promise<object|null>}
 */
export async function getAtlasDeviceDetail(deviceId) {
  if (!deviceId) return null;

  const start = Date.now();
  logger('atlas:detail', `Fetching detail for device ${deviceId}`, 'debug');

  try {
    const data = await atlasGet(`/organization/devices/${deviceId}`);
    logger('atlas:detail', `Detail fetched (${Date.now() - start} ms)`, 'debug');
    return data;
  } catch (err) {
    logger('atlas:detail', `Failed for ${deviceId}: ${err.message}`);
    return null;
  }
}

/**
 * Convenience: Get detailed device(s) for a store (find → fetch detail)
 * Returns array (usually 0–1 items in practice)
 */
export async function getAtlasDeviceForStore(storeNumber) {
  const candidates = await findAtlasDevicesForStore(storeNumber);

  if (candidates.length === 0) {
    return [];
  }

  // Fetch details for all matches (parallel)
  const details = await Promise.allSettled(
    candidates.map(c => getAtlasDeviceDetail(c.id))
  );

  const successful = details
    .filter(r => r.status === 'fulfilled')
    .map(r => r.value)
    .filter(Boolean);

  if (successful.length === 0) {
    logger('atlas:getForStore', `No successful detail fetches for store ${storeNumber}`);
  }

  return successful;
}