// services/enrichment/merakiMatcher.js
//
// Unified, high-quality Meraki client matching logic.
// This is the single source of truth for matching MDM/Atlas devices
// to Meraki clients across the entire application.
//
// Extracted and unified from multiple locations (avDeviceBuilder, deviceService, etc.)
// to eliminate duplication and make improvements in one place.

import { logger } from '../../utils/logger.js';
import { normalizePlayerName } from '../../utils/normalize.js';
import { normalizeMac } from './normalizers.js';

/**
 * Finds the best matching Meraki client for a given device (MDM or Atlas).
 * Uses multiple strategies in priority order for maximum reliability,
 * especially with country-prefixed identifiers (US, CA, etc.).
 *
 * @param {Object} device - The source device (from MDM or Atlas)
 * @param {Array} allMerakiClients - List of Meraki clients
 * @param {Object} [options]
 * @param {boolean} [options.debug] - Enable extra debug logging for a specific device
 * @returns {Object|null} The best matching Meraki client, or null
 */
export function findBestMerakiClientMatch(device, allMerakiClients, options = {}) {
  if (!device || !allMerakiClients || allMerakiClients.length === 0) {
    return null;
  }

  const identifier = (device.identifier || '').toUpperCase().trim();
  const username = (
    device.mdmData?.UserName ||
    device.mdmData?.DeviceFriendlyName ||
    device.mdmData?.DeviceReportedName ||
    ''
  ).toUpperCase().trim();

  // Extract country prefix if present (US, CA, MX, EU, AU, ...)
  const countryMatch = identifier.match(/^(US|CA|MX|EU|AU)/i);
  const countryPrefix = countryMatch ? countryMatch[1].toUpperCase() : 'US';

  // Stripped version without country prefix (e.g. 001024MSCAE)
  const strippedId = identifier.replace(/^(US|CA|MX|EU|AU)/i, '').trim();

  // Atlas support: extract IP/MAC from atlasData or summary (for AMPs in rich/build paths)
  // This allows IP-based matching when name/desc doesn't match (common for AMPs)
  const atlasIp = (
    device.atlasData?.state?.IpAddress ||
    device.atlasData?.ipAddress ||
    device.atlasDataSummary?.ipAddress ||
    device.ip ||
    ''
  ).trim().toLowerCase();

  const atlasMac = normalizeMac(
    device.atlasData?.mac ||
    device.atlasDataSummary?.macAddress ||
    ''
  );

  const shouldDebug = options.debug || identifier.startsWith('CA');

  if (shouldDebug) {
    logger('enrichment:meraki', `Matching attempt for ${identifier}`);
    logger('enrichment:meraki', `Username: ${username}, Stripped: ${strippedId}, atlasIp: ${atlasIp}, atlasMac: ${atlasMac}`);
  }

  // Track the best (most recent by lastSeen) match across *all* strategies.
  // This handles the case of multiple client entries for the same AV identifier (e.g. historical
  // connections on different ports/APs over the timespan window). We return the freshest one.
  let bestMatch = null;
  let bestTime = -1;

  for (const listItem of allMerakiClients) {
    // Unwrap: in chat shape, the "clients" list items from enrichAll are wrapped {name, meraki: {...client data...}, ...}
    // In rich shape, they are raw client objects with description/user/mac/ip at top.
    // Support both so matching works uniformly for MDM and Atlas in both paths.
    const c = listItem.meraki || listItem;  // the inner client data if wrapped
    const desc = (c.description || listItem.name || '').toUpperCase().trim();
    const userField = (c.user || '').toUpperCase().trim();
    const clientMac = normalizeMac(c.mac);

    let matchedThis = false;

    // Strategy 1: Exact full identifier match (best case)
    if (desc === identifier || userField === identifier) {
      matchedThis = true;
      if (shouldDebug) logger('enrichment:meraki', `✓ Exact match for ${identifier}`);
    }

    // Strategy 2: Username / friendly name match
    if (username && (desc.includes(username) || userField.includes(username))) {
      matchedThis = true;
      if (shouldDebug) logger('enrichment:meraki', `✓ Username match for ${identifier}`);
    }

    // Strategy 3: Stripped ID match (handles CA001024MSCAE vs 001024MSCAE)
    if (strippedId && (desc.includes(strippedId) || userField.includes(strippedId))) {
      matchedThis = true;
      if (shouldDebug) logger('enrichment:meraki', `✓ Stripped ID match for ${identifier}`);
    }

    // Strategy 4: Country + stripped fallback
    if (countryPrefix && strippedId) {
      const countryStripped = `${countryPrefix}${strippedId}`;
      if (desc.includes(countryStripped) || userField.includes(countryStripped)) {
        matchedThis = true;
        if (shouldDebug) logger('enrichment:meraki', `✓ Country+stripped match for ${identifier}`);
      }
    }

    // Strategy 5: MAC address fallback (very reliable)
    // Support various shapes: mdmData.MacAddress (AV), direct .mac or .MacAddress (phones, Webex, etc.)
    // Also atlas for AMPs (from atlasData or summary in base prepared devices)
    const deviceMac = device.mdmData?.MacAddress || device.mac || device.MacAddress || atlasMac;
    if (deviceMac) {
      const devMac = normalizeMac(deviceMac);
      if (clientMac && clientMac === devMac) {
        matchedThis = true;
        if (shouldDebug) logger('enrichment:meraki', `✓ MAC match for ${identifier}`);
      }
    }

    // Strategy 6: IP address match (for Atlas AMPs that may not expose friendly name in Meraki clients)
    if (atlasIp) {
      const clientIp = (c.ip || '').trim().toLowerCase();
      if (clientIp && clientIp === atlasIp) {
        matchedThis = true;
        if (shouldDebug) logger('enrichment:meraki', `✓ IP match for ${identifier}`);
      }
    }

    if (matchedThis) {
      // Pick the most recent by lastSeen (Meraki provides lastSeen on client records).
      // This ensures that when multiple entries exist for the same device (different ports/sessions),
      // we attach the current/freshest one (e.g. the one on port 35 for VW01).
      const thisTime = c.lastSeen ? Date.parse(c.lastSeen) || 0 : 0;
      if (bestMatch === null || thisTime > bestTime) {
        bestMatch = listItem;
        bestTime = thisTime;
      }
      // Continue scanning to find any even fresher match via other strategies or later records.
    }
  }

  if (bestMatch) {
    const chosen = bestMatch.meraki || bestMatch;
    if (shouldDebug || identifier.includes('2477')) {
      logger('enrichment:meraki', `✓ Most recent Meraki client chosen for ${identifier} (lastSeen=${chosen.lastSeen || 'n/a'}, port=${chosen.switchport || chosen.recentDevicePort || 'n/a'})`);
    }
    return bestMatch;  // return the list item (wrapped or raw) for consistent downstream handling
  }

  if (shouldDebug) {
    logger('enrichment:meraki', `✗ No match found for ${identifier}`, 'debug');
  }

  return null;
}

/**
 * Convenience wrapper that also enriches the device object in place
 * (for backward compatibility during migration).
 */
export async function enrichDeviceWithBestMerakiMatch(device, allMerakiClients, portStatusCache) {
  const match = findBestMerakiClientMatch(device, allMerakiClients);

  if (!match) {
    return device;
  }

  // Basic enrichment (can be extended later)
  device.meraki = {
    ...(device.meraki || {}),
    client: match,
    connectionType:
      match.recentDeviceConnection === 'Wireless' || match.ssid ? 'Wireless' : 'Wired',
    mac: match.mac,
    ip: match.ip,
    // Note: port enrichment can be added here or kept separate
  };

  return device;
}