/* @flow */
import PromiseQueue from 'promise-queue-observable';

import { config as AWSConfig, CognitoIdentityCredentials, CognitoSyncManager } from 'aws-sdk';
import 'amazon-cognito-js';

import {
  CognitoUserPool,
  CognitoUser,
  AuthenticationDetails,
  CognitoUserAttribute,
} from 'amazon-cognito-identity-js';

export type CognitoAuthenticator$Config = {
  log: boolean | 'warn' | 'error' | 'debug',
};

const tryJSONParse = (val: mixed): Object =>
  typeof val === 'object'
    ? val
    : // $FlowIgnore
      do {
        let v;
        try {
          v = JSON.parse(val);
        } catch (e) {
          v = val;
        } finally {
          v; // eslint-disable-line
        }
      };

export const toAWSAttribute = {
  userLocale: 'locale',
  userEmail: 'email',
  firstName: 'name',
  lastName: 'family_name',
  username: 'preferred_username',
  userPhoneNumber: 'phone_number',
  userAddress: 'address',
  phoneVerified: 'phone_number_verified',
  emailVerified: 'email_verified',
  dealerIdentityID: 'custom:dealerIdentityID',
  company: 'custom: company',
  latitude: 'custom:company_latitude',
  longitude: 'custom:company_longitude',
};

export const fromAWSAttribute = {
  email: 'userEmail',
  name: 'firstName',
  family_name: 'lastName',
  locale: 'userLocale',
  preferred_username: 'username',
  phone_number: 'userPhoneNumber',
  email_verified: 'emailVerified',
  phone_number_verified: 'phoneVerified',
  address: 'userAddress',
  'custom:dealerIdentityID': 'dealerIdentityID',
  'custom:company': 'company',
  'custom:company_latitude': 'companyLat',
  'custom:company_longitude': 'companyLon',
};

let Authenticator;

const handleSynchronizeUserData = (dataManager /* , initialRecords */) =>
  new Promise((resolve, reject) => {
    dataManager.synchronize({
      onSuccess(dataset, newRecords) {
        // if (observer) {
        //   observer.publish('data_sync', 'success', dataset, newRecords);
        // }
        resolve(['success', dataset, newRecords]);
      },
      onFailure(error) {
        // console.error('DataSync Error: ', error.message);
        // if (observer) {
        //   observer.publish('data_sync', 'error', error.message);
        // }
        resolve(['error', error]);
      },
      onConflict(dataset, conflicts, callback) {
        console.warn('Dataset Conflict! ', conflicts);
        // if (observer) {
        //   observer.publish('data_sync', 'conflict', conflicts, callback);
        // }
        resolve(['conflict', dataset, conflicts, callback]);
      },
      observersetDeleted(dataset, datasetName, callback) {
        // console.info('Dataset Deleted: ', datasetName);
        // observer.publish('data_sync', 'deleted', datasetName);
        resolve(['deleted', dataset, datasetName, callback]);
        return callback(true);
      },
      observersetMerged(dataset, datasetNames, callback) {
        // console.info('Dataset Merged: ', datasetNames);
        // observer.publish('data_sync', 'merged', datasetNames);
        resolve(['merged', dataset, datasetNames, callback]);
        return callback(true);
      },
    });
  });

const handleFormatDataRecords = records =>
  records.reduce((p, c) => {
    p[c.key] = tryJSONParse(c.value);
    return p;
  }, {});

const handleGetAllRecords = dataManager =>
  new Promise((resolve, reject) => {
    handleSynchronizeUserData(dataManager)
      .then(([result, ...args]) =>
        dataManager.getAllRecords((err, rawRecords) => {
          if (err) {
            console.error('Failed to Get All User Records: ', err.message);
            return reject('Failed to Get User Data Records');
          }

          const dealerIdentityID = dataManager.getIdentityId();

          const records = {
            dealerIdentityID,
            data: handleFormatDataRecords(rawRecords),
            manager: dataManager,
            sync: () => handleSynchronizeUserData(dataManager),
            getAll: () => handleGetAllRecords(dataManager),
          };

          return resolve(records);
        }),
      )
      .catch(err => {
        console.error('Failed to Get User Recors: ', err);
      });
  });

const getCredentials = (Username: string, Password: string): Class<AuthenticationDetails> =>
  new AuthenticationDetails({
    Username,
    Password,
  });

const parseUserAttributes = attributes =>
  attributes.reduce((p, c = {}) => {
    const { Name, Value } = c;
    if (fromAWSAttribute[Name]) {
      p[fromAWSAttribute[Name]] = Value;
    } else {
      p[Name] = Value;
    }
    return p;
  }, {});

const formatUserAttributes = attributes => {
  const formatted = [];
  for (const name of Object.keys(attributes)) {
    formatted.push(
      new CognitoUserAttribute({
        Name: toAWSAttribute[name] || name,
        Value: attributes[name],
      }),
    );
  }
  return formatted;
};

const getSessionIDToken = (session): string => session.getIdToken().getJwtToken();

function publishConfirmedRegistrationCode(user, code: string, observer) {
  // console.info('Submitting User Registration Code: ', code);
  return user.confirmRegistration(String(code), true, (err, result) => {
    if (err) {
      console.error('Failed to Publish Confirmed Registration Code: ', err.message);
      observer.publish('error', err.message);
    } else {
      observer.publish('success', result);
    }
    observer.cancel();
  });
}

class CognitoAuthenticator {
  constructor(config?: CognitoAuthenticator$Config = {}) {
    this.config = {
      region: 'us-west-2',
      ...config,
    };
    AWSConfig.region = this.config.region;
    this.setDefaults();
  }

  setDefaults = (): void => {
    this.state = {
      pool: undefined,
      mfa: undefined,
    };
    // AWS Classes / Instances
    this.aws = {
      user: undefined,
      userPool: undefined,
      session: undefined,
      identity: undefined,
      sync: undefined,
      dataManager: undefined,
    };
  };

  setPool = (params): Class<CognitoAuthenticator> => {
    const { ClientId, UserPoolId } = params;
    this.state.pool = params;
    if (ClientId && UserPoolId) {
      this.aws.userPool = new CognitoUserPool(params);
    }
    return this;
  };

  setIdentity = (params): Class<CognitoAuthenticator> => {
    this.state.identity = params;
    return this;
  };

  refreshUserFromStorage = (): Class<CognitoAuthenticator> => {
    if (this.aws.userPool) {
      const user = this.aws.userPool.getCurrentUser();
      if (user) {
        this.aws.user = user;
      }
    }
    return this;
  };

  setUser = (Username: string): Class<CognitoAuthenticator> => {
    if (!this.aws.userPool) {
      throw new Error('You must setup the User Pool before setting the user!');
    } else {
      this.aws.user = new CognitoUser({
        Username,
        Pool: this.aws.userPool,
      });
    }
    return this;
  };

  setSession = (session): Class<CognitoAuthenticator> => {
    if (!session.isValid()) {
      throw new Error('Tried to set an invalid Session on Authenticator');
    }
    this.aws.session = session;
    return this;
  };

  setPassword = (prevPassword: string, newPassword: string): Promise<*> =>
    new Promise((resolve, reject) =>
      this.refreshSessionIfNeeded().then(() =>
        this.getUser().changePassword(prevPassword, newPassword, (err, result) => {
          if (err) {
            console.error('Failed to Set User Password: ', err.message);
            return reject(err.message);
          }
          return resolve(result);
        }),
      ),
    );

  getPool = (required?: boolean = true) => {
    if (this.aws.userPool) {
      return this.aws.userPool;
    }
    if (required) {
      throw new Error('Attempted to Get User Pool before it was setup!');
    }
  };

  getUser = (required?: boolean = true) => {
    if (this.aws.user) {
      return this.aws.user;
    }
    if (required) {
      throw new Error('Attempted to Get User before it was setup!');
    }
  };

  getUsername = (required?: boolean = true) => {
    if (this.aws.user) {
      return this.aws.user.getUsername();
    }
    if (required) {
      throw new Error('Attempted to Get Username before it was setup!');
    }
  };

  getSession = (required?: boolean = true) => {
    if (this.aws.session && typeof this.aws.session.isValid === 'function') {
      return this.aws.session;
    }
    if (required) {
      throw new Error('Attempted to Get User Session before it was setup!');
    }
  };

  getRefreshToken = (): string => this.getSession().getRefreshToken();

  getAccessToken = (): string => getSessionIDToken(this.getSession());

  logout = (): Class<CognitoAuthenticator> => {
    const user = this.getUser(false);
    if (user) {
      user.signOut();
    }
    const userPool = this.aws.userPool;
    const poolParams = this.state.pool;

    this.setDefaults();

    // dont reset the userPool on logout
    this.aws.userPool = userPool;
    this.state.pool = poolParams;

    clearAWSCredentialsCache();
    return this;
  };

  startSignup = (username: string, password: string, attributes: Object) => {
    const observer = new PromiseQueue();

    this.getPool().signUp(username, password, attributes, null, (err, result) => {
      if (err) {
        console.error('Signup Error: ', err.message);
        observer.publish('error', err, this);
      } else {
        this.setUser(username);
        const callback = code => publishConfirmedRegistrationCode(this.getUser(), code, observer);
        observer.publish('verify', result, callback, this);
      }
    });

    return { observer };
  };

  startLogin = (username: string, password: string) => {
    // console.log('Start Login: ', username, password);
    const observer = new PromiseQueue();

    const credentials = getCredentials(username, password);

    clearAWSCredentialsCache();

    const onSuccess = session => {
      observer.publish('success', this.setSession(session).getSession(), this);
      observer.cancel();
    };

    const onFailure = err => {
      console.error('Failed to Login User: ', err.message);
      observer.publish('error', err, this);
      observer.cancel();
    };

    const mfaRequired = data => {
      console.info('Multi-Factor Validation Required: ', data);
      const callback = code => {
        const user = this.getUser();
        user.sendMFACode(String(code), { onSuccess, onFailure, newPasswordRequired });
      };
      observer.publish('verify', data, callback, this);
    };

    const newPasswordRequired = (userAttributes, requiredAttributes) => {
      const data = { userAttributes, requiredAttributes };
      // User was signed up by an admin and must provide new
      // password and required attributes, if any, to complete
      // authentication.
      console.log('New Password Required');
      // the api doesn't accept this field back
      delete userAttributes.email_verified;

      const callback = newPassword => {
        this.getUser().completeNewPasswordChallenge(newPassword, userAttributes, {
          onSuccess,
          onFailure,
          mfaRequired,
        });
      };

      observer.publish('reset_password', data, callback, this);
    };

    this.setUser(username)
      .getUser()
      .authenticateUser(credentials, {
        onSuccess,
        onFailure,
        mfaRequired,
        newPasswordRequired,
      });

    return { observer };
  };

  startForgotPassword = (username: string) => {
    const observer = new PromiseQueue();
    this.setUser(username);
    const onSuccess = () => {
      // console.info('Forgot Password Success!');
      observer.publish('success', this);
      observer.cancel();
    };

    const onFailure = err => {
      console.error('Failed to Reset Password: ', err.message);
      observer.publish('error', err, this);
      observer.cancel();
    };

    const inputVerificationCode = data => {
      console.info('Forgot Info Sent, Verification Required: ', data);
      const callback = (code, newPassword) => {
        this.getUser().confirmPassword(String(code), newPassword, {
          onSuccess,
          onFailure,
        });
      };
      observer.publish('verify', data, callback);
    };

    this.setUser(username)
      .getUser()
      .forgotPassword({
        onSuccess,
        onFailure,
        inputVerificationCode,
      });

    return { observer };
  };

  startSetUserAttributes = (attributes: Object) => {
    const observer = new PromiseQueue();

    const onSuccess = result => {
      observer.publish('success', result);
      observer.cancel();
    };

    const onFailure = err => {
      console.error('Failed to Set User Attributes: ', err.message);
      observer.publish('error', err);
      observer.cancel();
      return err;
    };

    const inputVerificationCode = async result => {
      const deliveries = result.CodeDeliveryDetailsList;
      while (deliveries.length > 0) {
        const delivery = deliveries.shift();
        // eslint-disable-next-line
        await new Promise((resolve, reject) => {
          const callback = code => {
            this.getUser().verifyAttribute(delivery.AttributeName, String(code), {
              onSuccess: success => {
                console.log('Attribute Verified: ', success);
                if (deliveries.length === 0) {
                  resolve(onSuccess(success));
                } else {
                  resolve();
                }
              },
              onFailure: err => {
                reject(onFailure(err));
              },
            });
          };
          // simulate the same style that is used for standard verification of
          // attributes.
          observer.publish('verify', { CodeDeliveryDetails: delivery }, callback);
          // finish promise
        });
        // handle next delivery
      }
    };

    // eslint-disable-next-line
    this.refreshSessionIfNeeded().then(() => {
      const formatted = formatUserAttributes(attributes);
      if (formatted.length === 0) {
        console.error('Formatted Attributes was Empty');
        observer.publish('error', 'Formatted Attributes was Empty');
        return observer.cancel();
      }

      return this.getUser().updateAttributes(formatted, {
        onSuccess,
        onFailure,
        inputVerificationCode,
      });
    });

    return { observer };
  };

  startVerifyAttribute = (attribute?: string = 'email') => {
    const observer = new PromiseQueue();

    const onSuccess = result => {
      observer.publish('success', result);
      observer.cancel();
    };

    const onFailure = err => {
      observer.publish('error', err);
      observer.cancel();
    };

    const inputVerificationCode = result => {
      const callback = code => {
        if (code) {
          return this.getUser().verifyAttribute(attribute, String(code), {
            onSuccess,
            onFailure,
          });
        }
        return observer.cancel();
      };
      observer.publish('verify', result, callback);
    };

    this.refreshSessionIfNeeded()
      .then(() =>
        this.getUser().getAttributeVerificationCode(attribute, {
          onSuccess,
          onFailure,
          inputVerificationCode,
        }),
      )
      .catch(err => observer.publish('error', err));

    return { observer };
  };

  refreshUserAttributes = (): Promise<*> =>
    new Promise((resolve, reject) =>
      this.refreshSessionIfNeeded().then(() =>
        this.getUser().getUserAttributes((err, attributes) => {
          if (err) {
            console.error('[getUserAttributes] Failed: ', err.message);
            return reject(err.message);
          }
          resolve(parseUserAttributes(attributes));
        }),
      ),
    );

  refreshUserSession = (force?: boolean = false): Promise<*> =>
    new Promise((resolve, reject) =>
      this.getUser().getSession((err, session) => {
        if (err) {
          console.error('Failed to Refresh User Session from Library: ', err.message);
          return reject('Refresh Session Failed');
        }
        if (force || !session.isValid()) {
          // manually set the session then attempt to refresh it
          this.aws.session = session;
          return resolve(this.refreshSession());
        }
        resolve(this.setSession(session).getSession());
      }),
    );

  refreshSessionIfNeeded = (): Promise<*> =>
    new Promise(resolve => {
      const session = this.getSession();
      if (session.isValid()) {
        return resolve(session);
      }
      return resolve(this.refreshSession());
    });

  refreshSession = (): Promise<*> =>
    new Promise((resolve, reject) => {
      this.getUser().refreshSession(this.getRefreshToken(), (err, session) => {
        if (err) {
          console.error('Failed to Refresh User Session: ', err.message);
          return reject(err.message);
        } else if (!session.isValid()) {
          console.error('Refreshed Session is Not Valid!');
          return reject('Failed to Refresh Session');
        }
        return resolve(this.setSession(session).getSession());
      });
    });

  refreshUserDevices = (limit?: number = 30, page = null): Promise<*> =>
    new Promise((resolve, reject) =>
      this.refreshSessionIfNeeded().then(() =>
        this.getUser().listDevices(limit, page, {
          onSuccess: result => resolve(result),
          onFailure: err => {
            console.error('Failed to Refresh User Devices: ', err.message);
            return reject(err.message);
          },
        }),
      ),
    );

  refreshAccessTokensIfNeeded = (): Promise<string> =>
    this.refreshSessionIfNeeded().then(session => getSessionIDToken(session));

  refreshAccessTokens = (): Promise<string> =>
    this.refreshSession().then(session => getSessionIDToken(session));

  refreshIdentityPool = () => {
    const identity = this.state.identity;
    if (!identity) {
      throw new Error(
        'Tried to refresh Identity Pool before setting its params with setIdentity()!',
      );
    }
    return this.refreshSession()
      .then(session => {
        const token = getSessionIDToken(session);
        const userPool = this.getPool();
        const { region } = this.config;
        this.aws.identity = new CognitoIdentityCredentials({
          ...identity,
          Logins: {
            [`cognito-idp.${region}.amazonaws.com/${userPool.getUserPoolId()}`]: token,
          },
        });
        AWSConfig.credentials = this.aws.identity;
        return AWSConfig.credentials.refreshPromise();
      })
      .catch(err => {
        console.error('Failed to Refresh Identity Pool: ', err.message);
        throw err;
      });
  };

  refreshIdentityPoolIfNeeded = () => {
    const identity = this.state.identity;
    if (!identity) {
      throw new Error(
        'Tried to refresh Identity Pool before setting its params with setIdentity()!',
      );
    }
    return this.refreshSessionIfNeeded()
      .then(session => {
        const token = getSessionIDToken(session);
        const userPool = this.getPool();
        const { region } = this.config;
        this.aws.identity = new CognitoIdentityCredentials({
          ...identity,
          Logins: {
            [`cognito-idp.${region}.amazonaws.com/${userPool.getUserPoolId()}`]: token,
          },
        });
        AWSConfig.credentials = this.aws.identity;
        return AWSConfig.credentials.refreshPromise();
      })
      .catch(err => {
        console.error('Failed to Refresh Identity Pool: ', err.message);
        throw err;
      });
  };

  removeUserDevice = (deviceKey: string): Promise<string> =>
    new Promise((resolve, reject) =>
      this.refreshSessionIfNeeded().then(() =>
        this.getUser().forgetSpecificDevice(deviceKey, {
          onFailure: err => reject(err.message),
          onSuccess: () => resolve(deviceKey),
        }),
      ),
    );

  refreshUserDataSync = (dataset?: string = 'settings', force?: boolean = false): Promise<*> =>
    new Promise((resolve, reject) => {
      const getAWSCredentials = () =>
        AWSConfig.credentials.get(() => {
          this.aws.sync = new CognitoSyncManager();
          return this.aws.sync.openOrCreateDataset(dataset, (err, dataManager) => {
            if (err) {
              console.error('Failed to Open User Data Set: ', dataset, err.message);
              return reject('Failed to Open UserData');
            }
            console.log(dataManager);
            this.aws.dataManager = dataManager;
            return resolve(handleGetAllRecords(dataManager));
          });
        });
      if (force) {
        return this.refreshIdentityPool().then(() => getAWSCredentials());
      }
      return this.refreshIdentityPoolIfNeeded().then(() => getAWSCredentials());
    });
}

export function clearAWSCredentialsCache(): void {
  if (AWSConfig.credentials && AWSConfig.credentials.clearCachedId) {
    AWSConfig.credentials.clearCachedId();
  }
}

export function createCognitoAuthenticator(
  config?: CognitoAuthenticator$Config,
): Class<CognitoAuthenticator> {
  Authenticator = new CognitoAuthenticator(config);
  return Authenticator;
}

export function getCognitoAuthenticator(
  config?: CognitoAuthenticator$Config,
): Class<CognitoAuthenticator> {
  if (!Authenticator && config) {
    return createCognitoAuthenticator(config);
  }
  return Authenticator;
}