/**
 * ESP32 WiFi Provisioning Service
 *
 * Handles BLE communication with WellNuo ESP32 sensors (WP_xxx_xxxxxx)
 * for WiFi configuration and provisioning.
 *
 * Uses @orbital-systems/react-native-esp-idf-provisioning which wraps
 * Espressif's official provisioning libraries.
 */

import {
  ESPProvisionManager,
  ESPDevice,
  ESPTransport,
  ESPSecurity,
  type ESPWifi,
} from '@orbital-systems/react-native-esp-idf-provisioning';
import { Platform, PermissionsAndroid, Alert } from 'react-native';

// WellNuo device prefix (matches WP_xxx_xxxxxx pattern)
const WELLNUO_DEVICE_PREFIX = 'WP_';

// Security mode - most ESP32 devices use secure or secure2
// Try unsecure first if device doesn't have proof-of-possession
const DEFAULT_SECURITY = ESPSecurity.unsecure;

export interface WellNuoDevice {
  name: string;
  device: ESPDevice;
  wellId?: string;      // Extracted from name: WP_<wellId>_<mac>
  macPart?: string;     // Last part of MAC address
}

export interface WifiNetwork {
  ssid: string;
  rssi: number;
  auth: string;
}

class ESPProvisioningService {
  private connectedDevice: ESPDevice | null = null;
  private isScanning = false;

  /**
   * Request necessary permissions for BLE on Android
   */
  async requestPermissions(): Promise<boolean> {
    if (Platform.OS !== 'android') {
      return true;
    }

    try {
      const granted = await PermissionsAndroid.requestMultiple([
        PermissionsAndroid.PERMISSIONS.BLUETOOTH_SCAN,
        PermissionsAndroid.PERMISSIONS.BLUETOOTH_CONNECT,
        PermissionsAndroid.PERMISSIONS.ACCESS_FINE_LOCATION,
      ]);

      const allGranted = Object.values(granted).every(
        (status) => status === PermissionsAndroid.RESULTS.GRANTED
      );

      if (!allGranted) {
        console.warn('[ESP] Some permissions were not granted:', granted);
      }

      return allGranted;
    } catch (error) {
      console.error('[ESP] Permission request error:', error);
      return false;
    }
  }

  /**
   * Scan for WellNuo ESP32 devices
   * Returns list of devices matching WP_xxx_xxxxxx pattern
   */
  async scanForDevices(timeoutMs = 10000): Promise<WellNuoDevice[]> {
    if (this.isScanning) {
      console.warn('[ESP] Already scanning, please wait');
      return [];
    }

    const hasPermissions = await this.requestPermissions();
    if (!hasPermissions) {
      throw new Error('Bluetooth permissions not granted');
    }

    this.isScanning = true;
    console.log('[ESP] Starting BLE scan for WellNuo devices...');

    try {
      const devices = await ESPProvisionManager.searchESPDevices(
        WELLNUO_DEVICE_PREFIX,
        ESPTransport.ble,
        DEFAULT_SECURITY
      );

      console.log(`[ESP] Found ${devices.length} WellNuo device(s)`);

      return devices.map((device: ESPDevice) => {
        // Parse device name: WP_<wellId>_<macPart>
        const parts = device.name?.split('_') || [];
        return {
          name: device.name || 'Unknown',
          device,
          wellId: parts[1],
          macPart: parts[2],
        };
      });
    } catch (error) {
      console.error('[ESP] Scan error:', error);
      throw error;
    } finally {
      this.isScanning = false;
    }
  }

  /**
   * Connect to a WellNuo device
   * @param device - The device to connect to
   * @param proofOfPossession - Optional PoP for secure devices
   */
  async connect(
    device: ESPDevice,
    proofOfPossession?: string
  ): Promise<boolean> {
    if (this.connectedDevice) {
      console.warn('[ESP] Already connected, disconnecting first...');
      await this.disconnect();
    }

    console.log(`[ESP] Connecting to ${device.name}...`);

    try {
      // Try without PoP first (unsecure mode)
      await device.connect(proofOfPossession || null);
      this.connectedDevice = device;
      console.log(`[ESP] Connected to ${device.name}`);
      return true;
    } catch (error) {
      console.error('[ESP] Connection error:', error);
      throw error;
    }
  }

  /**
   * Scan for available WiFi networks through connected device
   */
  async scanWifiNetworks(): Promise<WifiNetwork[]> {
    if (!this.connectedDevice) {
      throw new Error('Not connected to any device');
    }

    console.log('[ESP] Scanning for WiFi networks...');

    try {
      const wifiList = await this.connectedDevice.scanWifiList();

      console.log(`[ESP] Found ${wifiList.length} WiFi network(s)`);

      return wifiList.map((wifi: ESPWifi) => ({
        ssid: wifi.ssid,
        rssi: wifi.rssi,
        auth: this.getAuthModeName(wifi.auth),
      }));
    } catch (error) {
      console.error('[ESP] WiFi scan error:', error);
      throw error;
    }
  }

  /**
   * Provision device with WiFi credentials
   * @param ssid - WiFi network name
   * @param password - WiFi password
   */
  async provisionWifi(ssid: string, password: string): Promise<boolean> {
    if (!this.connectedDevice) {
      throw new Error('Not connected to any device');
    }

    console.log(`[ESP] Provisioning WiFi: ${ssid}`);

    try {
      await this.connectedDevice.provision(ssid, password);
      console.log('[ESP] WiFi provisioning successful!');
      return true;
    } catch (error) {
      console.error('[ESP] Provisioning error:', error);
      throw error;
    }
  }

  /**
   * Disconnect from current device
   */
  async disconnect(): Promise<void> {
    if (!this.connectedDevice) {
      return;
    }

    console.log(`[ESP] Disconnecting from ${this.connectedDevice.name}...`);

    try {
      this.connectedDevice.disconnect();
      this.connectedDevice = null;
      console.log('[ESP] Disconnected');
    } catch (error) {
      console.error('[ESP] Disconnect error:', error);
      this.connectedDevice = null;
    }
  }

  /**
   * Check if currently connected to a device
   */
  isConnected(): boolean {
    return this.connectedDevice !== null;
  }

  /**
   * Get currently connected device name
   */
  getConnectedDeviceName(): string | null {
    return this.connectedDevice?.name || null;
  }

  /**
   * Convert auth mode number to human-readable string
   */
  private getAuthModeName(authMode: number): string {
    const modes: Record<number, string> = {
      0: 'Open',
      1: 'WEP',
      2: 'WPA2 Enterprise',
      3: 'WPA2 PSK',
      4: 'WPA PSK',
      5: 'WPA/WPA2 PSK',
    };
    return modes[authMode] || `Unknown (${authMode})`;
  }
}

// Export singleton instance
export const espProvisioning = new ESPProvisioningService();

// Export types for components
export type { ESPDevice };