// Real BLE Manager для физических устройств

import { BleManager, Device, State } from 'react-native-ble-plx';
import { PermissionsAndroid, Platform } from 'react-native';
import { IBLEManager, WPDevice, WiFiNetwork, WiFiStatus, BLE_CONFIG, BLE_COMMANDS } from './types';
import base64 from 'react-native-base64';

export class RealBLEManager implements IBLEManager {
  private manager: BleManager;
  private connectedDevices = new Map<string, Device>();
  private scanning = false;

  constructor() {
    this.manager = new BleManager();
  }

  // Check and request permissions
  private async requestPermissions(): Promise<boolean> {
    if (Platform.OS === 'ios') {
      // iOS handles permissions automatically via Info.plist
      return true;
    }

    if (Platform.OS === 'android') {
      if (Platform.Version >= 31) {
        // Android 12+
        const granted = await PermissionsAndroid.requestMultiple([
          PermissionsAndroid.PERMISSIONS.BLUETOOTH_SCAN!,
          PermissionsAndroid.PERMISSIONS.BLUETOOTH_CONNECT!,
          PermissionsAndroid.PERMISSIONS.ACCESS_FINE_LOCATION!,
        ]);

        return Object.values(granted).every(
          status => status === PermissionsAndroid.RESULTS.GRANTED
        );
      } else {
        // Android < 12
        const granted = await PermissionsAndroid.request(
          PermissionsAndroid.PERMISSIONS.ACCESS_FINE_LOCATION!
        );
        return granted === PermissionsAndroid.RESULTS.GRANTED;
      }
    }

    return false;
  }

  // Check if Bluetooth is enabled
  private async isBluetoothEnabled(): Promise<boolean> {
    const state = await this.manager.state();
    return state === State.PoweredOn;
  }

  async scanDevices(): Promise<WPDevice[]> {
    const hasPermission = await this.requestPermissions();
    if (!hasPermission) {
      throw new Error('Bluetooth permissions not granted');
    }

    const isEnabled = await this.isBluetoothEnabled();
    if (!isEnabled) {
      throw new Error('Bluetooth is disabled. Please enable it in settings.');
    }

    const foundDevices = new Map<string, WPDevice>();

    return new Promise((resolve, reject) => {
      this.scanning = true;

      this.manager.startDeviceScan(
        null,
        { allowDuplicates: false },
        (error, device) => {
          if (error) {
            this.scanning = false;
            reject(error);
            return;
          }

          if (device && device.name?.startsWith(BLE_CONFIG.DEVICE_NAME_PREFIX)) {
            // Parse well_id from name (WP_497_81a14c -> 497)
            const wellIdMatch = device.name.match(/WP_(\d+)_/);
            const wellId = wellIdMatch ? parseInt(wellIdMatch[1], 10) : undefined;

            // Extract MAC from device name (last part after underscore)
            const macMatch = device.name.match(/_([a-fA-F0-9]{6})$/);
            const mac = macMatch ? macMatch[1].toUpperCase() : '';

            foundDevices.set(device.id, {
              id: device.id,
              name: device.name,
              mac: mac,
              rssi: device.rssi || -100,
              wellId,
            });
          }
        }
      );

      // Stop scan after timeout
      setTimeout(() => {
        this.stopScan();
        resolve(Array.from(foundDevices.values()));
      }, BLE_CONFIG.SCAN_TIMEOUT);
    });
  }

  stopScan(): void {
    if (this.scanning) {
      this.manager.stopDeviceScan();
      this.scanning = false;
    }
  }

  async connectDevice(deviceId: string): Promise<boolean> {
    try {
      const device = await this.manager.connectToDevice(deviceId);
      await device.discoverAllServicesAndCharacteristics();
      this.connectedDevices.set(deviceId, device);
      return true;
    } catch (error) {
      console.error('[BLE] Connection failed:', error);
      return false;
    }
  }

  async disconnectDevice(deviceId: string): Promise<void> {
    const device = this.connectedDevices.get(deviceId);
    if (device) {
      await device.cancelConnection();
      this.connectedDevices.delete(deviceId);
    }
  }

  isDeviceConnected(deviceId: string): boolean {
    return this.connectedDevices.has(deviceId);
  }

  async sendCommand(deviceId: string, command: string): Promise<string> {
    const device = this.connectedDevices.get(deviceId);
    if (!device) {
      throw new Error('Device not connected');
    }

    return new Promise(async (resolve, reject) => {
      let responseReceived = false;
      let response = '';

      try {
        // Subscribe to notifications
        device.monitorCharacteristicForService(
          BLE_CONFIG.SERVICE_UUID,
          BLE_CONFIG.CHAR_UUID,
          (error, characteristic) => {
            if (error) {
              if (!responseReceived) {
                responseReceived = true;
                reject(error);
              }
              return;
            }

            if (characteristic?.value) {
              const decoded = base64.decode(characteristic.value);
              response = decoded;
              responseReceived = true;
              resolve(decoded);
            }
          }
        );

        // Send command
        const encoded = base64.encode(command);
        await device.writeCharacteristicWithResponseForService(
          BLE_CONFIG.SERVICE_UUID,
          BLE_CONFIG.CHAR_UUID,
          encoded
        );

        // Timeout
        setTimeout(() => {
          if (!responseReceived) {
            responseReceived = true;
            reject(new Error('Command timeout'));
          }
        }, BLE_CONFIG.COMMAND_TIMEOUT);
      } catch (error) {
        reject(error);
      }
    });
  }

  async getWiFiList(deviceId: string): Promise<WiFiNetwork[]> {
    // Step 1: Unlock device
    const unlockResponse = await this.sendCommand(deviceId, BLE_COMMANDS.PIN_UNLOCK);
    if (!unlockResponse.includes('ok')) {
      throw new Error('Failed to unlock device');
    }

    // Step 2: Get WiFi list
    const listResponse = await this.sendCommand(deviceId, BLE_COMMANDS.GET_WIFI_LIST);

    // Parse response: "mac,XXXXXX|w|COUNT|SSID1,RSSI1|SSID2,RSSI2|..."
    const parts = listResponse.split('|');
    if (parts.length < 3) {
      throw new Error('Invalid WiFi list response');
    }

    const count = parseInt(parts[2], 10);
    if (count < 0) {
      if (count === -1) {
        throw new Error('WiFi scan in progress, please wait');
      }
      if (count === -2) {
        return []; // No networks found
      }
    }

    const networks: WiFiNetwork[] = [];
    for (let i = 3; i < parts.length; i++) {
      const [ssid, rssiStr] = parts[i].split(',');
      if (ssid && rssiStr) {
        networks.push({
          ssid: ssid.trim(),
          rssi: parseInt(rssiStr, 10),
        });
      }
    }

    // Sort by signal strength (strongest first)
    return networks.sort((a, b) => b.rssi - a.rssi);
  }

  async setWiFi(deviceId: string, ssid: string, password: string): Promise<boolean> {
    // Step 1: Unlock device
    const unlockResponse = await this.sendCommand(deviceId, BLE_COMMANDS.PIN_UNLOCK);
    if (!unlockResponse.includes('ok')) {
      throw new Error('Failed to unlock device');
    }

    // Step 2: Set WiFi credentials
    const command = `${BLE_COMMANDS.SET_WIFI}|${ssid},${password}`;
    const setResponse = await this.sendCommand(deviceId, command);

    // Parse response: "mac,XXXXXX|W|ok" or "mac,XXXXXX|W|fail"
    return setResponse.includes('|W|ok');
  }

  async getCurrentWiFi(deviceId: string): Promise<WiFiStatus | null> {
    // Step 1: Unlock device
    const unlockResponse = await this.sendCommand(deviceId, BLE_COMMANDS.PIN_UNLOCK);
    if (!unlockResponse.includes('ok')) {
      throw new Error('Failed to unlock device');
    }

    // Step 2: Get current WiFi status
    const statusResponse = await this.sendCommand(deviceId, BLE_COMMANDS.GET_WIFI_STATUS);

    // Parse response: "mac,XXXXXX|a|SSID,RSSI" or "mac,XXXXXX|a|,0" (not connected)
    const parts = statusResponse.split('|');
    if (parts.length < 3) {
      return null;
    }

    const [ssid, rssiStr] = parts[2].split(',');
    if (!ssid || ssid.trim() === '') {
      return null; // Not connected
    }

    return {
      ssid: ssid.trim(),
      rssi: parseInt(rssiStr, 10),
      connected: true,
    };
  }

  async rebootDevice(deviceId: string): Promise<void> {
    // Step 1: Unlock device
    await this.sendCommand(deviceId, BLE_COMMANDS.PIN_UNLOCK);

    // Step 2: Reboot (device will disconnect)
    await this.sendCommand(deviceId, BLE_COMMANDS.REBOOT);

    // Remove from connected devices
    this.connectedDevices.delete(deviceId);
  }
}