import {NativeModules, Platform, NativeEventEmitter} from 'react-native';
import {
    OnfidoAlpha2CountryCode,
    OnfidoCaptureType,
    OnfidoConfig,
    OnfidoCountryCode,
    OnfidoDocumentType,
    OnfidoError,
    OnfidoMediaResult,
    OnfidoResult
} from "./config_constants";
import { Base64 } from 'js-base64';

const {OnfidoSdk} = NativeModules;

const OndifoSdkModule = NativeModules.OnfidoSdk
const eventEmitter = new NativeEventEmitter(OndifoSdkModule)

type BiometricTokenCallback = {
    onTokenGenerated: (customerUserHash: string, biometricToken: string) => void;
    onTokenRequested: (customerUserHash: string, provideToken: (biometricToken: string) => void) => void;
};


const Onfido = {
    start(config: OnfidoConfig): Promise<OnfidoResult> {

        if (!config) {
            return configError("config is missing");
        }

        if (!config.sdkToken) {
            return configError("sdkToken is missing");
        }

        if (!config.sdkToken.match(/^[A-Za-z0-9-_=]+\.[A-Za-z0-9-_=]+\.?[A-Za-z0-9-_.+/=]*$/)) {
            return configError("sdkToken is not a valid jwt");
        }

        if (config.workflowRunId === undefined) {
            if (!config.flowSteps) {
                return configError("flowSteps configuration is missing");
            }

            if (config.flowSteps.captureDocument) {
                if (config.flowSteps.captureDocument.docType && !config.flowSteps.captureDocument.countryCode) {
                    return configError("countryCode needs to be a ISO 3166-1 3 letter code if docType is specified");
                }

                if (!config.flowSteps.captureDocument.docType && config.flowSteps.captureDocument.countryCode) {
                    return configError("docType needs to be provided if countryCode is specified");
                }

                if (config.flowSteps.captureDocument.docType && !(config.flowSteps.captureDocument.docType in OnfidoDocumentType)) {
                    return configError("docType is invalid");
                }


                if (config.flowSteps.captureDocument.countryCode) {
                    if (!(config.flowSteps.captureDocument.countryCode in OnfidoCountryCode)) {
                        return configError("countryCode is not a ISO 3166-1 3 letter code");
                    }

                    if (Platform.OS === "android") {
                        config.flowSteps.captureDocument.alpha2CountryCode = OnfidoAlpha2CountryCode[config.flowSteps.captureDocument.countryCode];
                    }
                }

                if (
                    config.flowSteps.captureDocument.allowedDocumentTypes &&
                    config.flowSteps.captureDocument.allowedDocumentTypes.length > 0
                ) {
                    if(!config.flowSteps.captureDocument.allowedDocumentTypes.every(doc => doc in OnfidoDocumentType)){
                        let invalidList = config.flowSteps.captureDocument.allowedDocumentTypes
                            .filter((value) => value !in OnfidoDocumentType)
                        return configError(`allowedDocumentTypes is invalid ${invalidList}`)
                    }
                    if(config.flowSteps.captureDocument.docType && config.flowSteps.captureDocument.countryCode){
                        return configError("We can either filter the documents on DocumentSelection screen, or skip the selection and go directly to capture")
                    }
                }
            }

            if (
                !config.flowSteps.captureDocument &&
                !config.flowSteps.captureFace &&
                !config.flowSteps.proofOfAddress
            ) {
                return configError("flowSteps is empty");
            }

            if (config.flowSteps.captureFace && !(config.flowSteps.captureFace.type in OnfidoCaptureType)) {
                return configError("Capture Face type is invalid");
            }
            
        }

    return OnfidoSdk.start(config).catch((error: any) => {
      console.log(error);
      throw error;
    });
  },

  addCustomMediaCallback(callback: (result: OnfidoMediaResult) => OnfidoMediaResult) {
    OnfidoSdk.withMediaCallbacksEnabled()

    // Removing any previously-added listener to avoid multiple invocations
    eventEmitter.removeAllListeners('onfidoMediaCallback');
    
    return eventEmitter.addListener('onfidoMediaCallback', callback);
  },

addBiometricTokenCallback(callback: BiometricTokenCallback): void {
    OnfidoSdk.withBiometricTokenCallback();

    eventEmitter.removeAllListeners('onTokenGenerated');
    eventEmitter.removeAllListeners('onTokenRequested');

    eventEmitter.addListener('onTokenGenerated', (event) => {
        callback.onTokenGenerated(event.customerUserHash, event.biometricToken)
    });
    eventEmitter.addListener('onTokenRequested', (event) => {
        callback.onTokenRequested(event.customerUserHash, (biometricToken) => {
            OnfidoSdk.provideBiometricToken(biometricToken)
        })
    });
  },

  byteArrayStringToBase64(byteArrayString: String) {
    let charString = '';

    // Iterate through the string and convert each number to string
    // Iteration starts from the 1st element to ignore brackets
    let currentNumber = '';
    for (let i = 1; i < byteArrayString.length; i++) {
      const char = byteArrayString.charAt(i);
      if ((char >= '0' && char <= '9') || char === '-') {
        currentNumber += char;
      } else {
        // Convert the collected number to string
        if (currentNumber) {
          const number = parseInt(currentNumber, 10);
          charString += String.fromCharCode(number & 0xFF);
          currentNumber = '';
        }
      }
    }

    // Convert to base64
    return Base64.btoa(charString);
  }
};

const configError = (message: string): Promise<OnfidoResult> => {
    const error: OnfidoError = new Error(message);
    error.code = "config_error";
    console.log(error);
    return Promise.reject(error);
};

export default Onfido