import IframeReference from './IframeReference';
import EventBus from './EventBus';
import UserStore from './UserStrore';
import type { ProfileData } from './models/ProfileData';
import type { FolderData } from './models/FolderData';
import { v4 as uuidv4 } from 'uuid';

export default class MessageBus {
  private static instance: MessageBus;
  private readonly origin: string;
  private messageListener: ((event: MessageEvent) => void) | null = null;
  private errors: { [key: string]: string } = {};

  private constructor(origin: string) {
    this.origin = origin;
  }

  public static getInstance(origin: string): MessageBus {
    if (!MessageBus.instance) {
      MessageBus.instance = new MessageBus(origin);
    }
    return MessageBus.instance;
  }

  public isReady(): Promise<void> {
    return new Promise<void>((resolve: () => void) => {
      const correlationId = uuidv4();
      this.initMessageListener(correlationId);

      const unsubscribe = EventBus.getInstance().on('IS_READY', (responseId: string) => {
        if (responseId !== correlationId) {
          return;
        }
        unsubscribe();
        this.destroyMessageListener();
        resolve();
      });
    });
  }

  public requestLink(): Promise<void> {
    return new Promise<void>((resolve: () => void, reject: (error: string) => void) => {
      const correlationId = uuidv4();
      this.initMessageListener(correlationId);

      const unsubscribe = EventBus.getInstance().on('LINK_ACCEPTED', (responseId: string, accessToken: string, refreshToken: string) => {
        if (responseId !== correlationId) {
          return;
        }
        unsubscribe();
        this.destroyMessageListener();
        UserStore.getInstance().connect(accessToken, refreshToken);
        resolve();
      });

      const unsubscribeError = EventBus.getInstance().on('ERROR_LINK_ACCEPTED', (responseId: string, error: string) => {
        if (responseId !== correlationId) {
          return;
        }
        unsubscribeError();
        this.destroyMessageListener();
        reject(error);
      });

      this.sendMessage({
        type: 'REQUEST_LINK'
      });
    });
  }

  public validateToken(): Promise<boolean> {
    return new Promise<boolean>((resolve: (isValid: boolean) => void, reject: (error: string) => void) => {
      const userStore = UserStore.getInstance();
      if (!userStore.isConnected()) {
        reject('User is not connected');
        return;
      }
      const accessToken = userStore.getAccessToken()!;
      const refreshToken = userStore.getRefreshToken()!;

      const correlationId = uuidv4();
      this.initMessageListener(correlationId);

      const unsubscribe = EventBus.getInstance().on('TOKEN_VALIDATED', (responseId: string, isValid: boolean) => {
        if (responseId !== correlationId) {
          return;
        }
        unsubscribe();
        this.destroyMessageListener();
        resolve(isValid);
      });

      const unsubscribeError = EventBus.getInstance().on('ERROR_TOKEN_VALIDATED', (responseId: string, error: string) => {
        if (responseId !== correlationId) {
          return;
        }
        unsubscribeError();
        this.destroyMessageListener();
        reject(error);
      });

      this.sendMessage({
        type: 'VALIDATE_TOKEN',
        accessToken,
        refreshToken
      });
    });
  }

  public renewToken(): Promise<void> {
    return new Promise<void>((resolve: () => void, reject: (error: string) => void) => {
      const userStore = UserStore.getInstance();
      if (!userStore.isConnected()) {
        reject('User is not connected');
        return;
      }
      const refreshToken = userStore.getRefreshToken()!;

      const correlationId = uuidv4();
      this.initMessageListener(correlationId);

      const unsubscribe = EventBus.getInstance().on('TOKEN_RENEWED', (responseId: string, accessToken: string, refreshToken: string) => {
        if (responseId !== correlationId) {
          return;
        }
        unsubscribe();
        this.destroyMessageListener();
        UserStore.getInstance().connect(accessToken, refreshToken);
        resolve();
      });

      const unsubscribeError = EventBus.getInstance().on('ERROR_TOKEN_RENEWED', (responseId: string, error: string) => {
        if (responseId !== correlationId) {
          return;
        }
        unsubscribeError();
        this.destroyMessageListener();
        reject(error);
      });

      this.sendMessage({
        type: 'RENEW_TOKEN',
        refreshToken
      });
    });
  }

  public getProcesses(): Promise<any> {
    return new Promise<any>((resolve: (processes: any) => void, reject: (error: string) => void) => {
      this.checkToken().then(() => {
        const correlationId = uuidv4();
        this.initMessageListener(correlationId);

        const unsubscribe = EventBus.getInstance().on('PROCESSES_RETRIEVED', (responseId: string, processes: any) => {
          if (responseId !== correlationId) {
            return;
          }
          unsubscribe();
          this.destroyMessageListener();
          resolve(processes);
        });

        const unsubscribeError = EventBus.getInstance().on('ERROR_PROCESSES_RETRIEVED', (responseId: string, error: string) => {
          if (responseId !== correlationId) {
            return;
          }
          unsubscribeError();
          this.destroyMessageListener();
          reject(error);
        });

        this.sendMessage({
          type: 'GET_PROCESSES'
        });
      }).catch(console.error);
    });
  }

  public getData(processId: string, stateId: string): Promise<any> {
    return new Promise<any>((resolve: (data: any) => void, reject: (error: string) => void) => {
      this.checkToken().then(() => {
        const userStore = UserStore.getInstance();
        const accessToken = userStore.getAccessToken()!;

        const correlationId = uuidv4();
        this.initMessageListener(correlationId);

        const unsubscribe = EventBus.getInstance().on('DATA_RETRIEVED', (responseId: string, data: any) => {
          if (responseId !== correlationId) {
            return;
          }
          unsubscribe();
          this.destroyMessageListener();
          resolve(data);
        });

        const unsubscribeError = EventBus.getInstance().on('ERROR_DATA_RETRIEVED', (responseId: string, error: string) => {
          if (responseId !== correlationId) {
            return;
          }
          unsubscribeError();
          this.destroyMessageListener();
          reject(error);
        });

        this.sendMessage({
          type: 'RETRIEVE_DATA',
          processId,
          stateId,
          token: accessToken
        });
      }).catch(console.error);
    });
  }

  public createProfile(profileData: ProfileData): Promise<ProfileData> {
    return new Promise<ProfileData>((resolve: (profileData: ProfileData) => void, reject: (error: string) => void) => {
      this.checkToken().then(() => {
        const userStore = UserStore.getInstance();
        const accessToken = userStore.getAccessToken()!;
        const refreshToken = userStore.getRefreshToken()!;

        const correlationId = uuidv4();
        this.initMessageListener(correlationId);

        const unsubscribe = EventBus.getInstance().on('PROFILE_CREATED', (responseId: string, profileData: ProfileData) => {
          if (responseId !== correlationId) {
            return;
          }
          unsubscribe();
          this.destroyMessageListener();
          resolve(profileData);
        });

        const unsubscribeError = EventBus.getInstance().on('ERROR_PROFILE_CREATED', (responseId: string, error: string) => {
          if (responseId !== correlationId) {
            return;
          }
          unsubscribeError();
          this.destroyMessageListener();
          reject(error);
        });

        this.sendMessage({
          type: 'CREATE_PROFILE',
          profileData,
          accessToken,
          refreshToken
        });
      }).catch(console.error);
    });
  }

  public createFolder(folderData: FolderData): Promise<FolderData> {
    return new Promise<FolderData>((resolve: (folderData: FolderData) => void, reject: (error: string) => void) => {
      this.checkToken().then(() => {
        const userStore = UserStore.getInstance();
        const accessToken = userStore.getAccessToken()!;

        const correlationId = uuidv4();
        this.initMessageListener(correlationId);

        const unsubscribe = EventBus.getInstance().on('FOLDER_CREATED', (responseId: string, folderData: FolderData) => {
          if (responseId !== correlationId) {
            return;
          }
          unsubscribe();
          this.destroyMessageListener();
          resolve(folderData);
        });

        const unsubscribeError = EventBus.getInstance().on('ERROR_FOLDER_CREATED', (responseId: string, error: string) => {
          if (responseId !== correlationId) {
            return;
          }
          unsubscribeError();
          this.destroyMessageListener();
          reject(error);
        });

        this.sendMessage({
          type: 'CREATE_FOLDER',
          folderData,
          token: accessToken
        });
      }).catch(console.error);
    });
  }

  private checkToken(): Promise<void> {
    return new Promise<void>((resolve: () => void, reject: (error: string) => void) => {
      this.validateToken().then((isValid: boolean) => {
        if (!isValid) {
          this.renewToken().then(resolve).catch(reject);
        } else {
          resolve();
        }
      }).catch(reject);
    });
  }

  private sendMessage(message: any): void {
    const iframe = IframeReference.getIframe();
    if (!iframe) {
      console.error('[MessageBus] sendMessage: iframe not found');
      return;
    }
    console.log('[MessageBus] sendMessage:', message);
    iframe.contentWindow?.postMessage(message, this.origin);
  }

  private initMessageListener(correlationId: string): void {
    this.destroyMessageListener();

    this.messageListener = this.handleMessage.bind(this, correlationId);
    window.addEventListener('message', this.messageListener);
  }

  private destroyMessageListener(): void {
    if (this.messageListener) {
      window.removeEventListener('message', this.messageListener);
      this.messageListener = null;
    }
  }

  private handleMessage(correlationId: string, event: MessageEvent): void {
    if (event.origin !== this.origin) {
      return;
    }

    if (!event.data || typeof event.data !== 'object') {
      return;
    }

    const message = event.data;
    switch (message.type) {
      case 'LISTENING':
        EventBus.getInstance().emit('IS_READY', correlationId);
        break;

      case 'LINK_ACCEPTED':
        if (this.errors[correlationId]) {
          const error = this.errors[correlationId];
          delete this.errors[correlationId];
          EventBus.getInstance().emit('ERROR_LINK_ACCEPTED', correlationId, error);
          return;
        }
        EventBus.getInstance().emit('MESSAGE_RECEIVED', message);
        EventBus.getInstance().emit('LINK_ACCEPTED', correlationId, message.accessToken, message.refreshToken);
        break;

      case 'VALIDATE_TOKEN':
        if (this.errors[correlationId]) {
          const error = this.errors[correlationId];
          delete this.errors[correlationId];
          EventBus.getInstance().emit('ERROR_TOKEN_VALIDATED', correlationId, error);
          return;
        }
        EventBus.getInstance().emit('MESSAGE_RECEIVED', message);
        EventBus.getInstance().emit('TOKEN_VALIDATED', correlationId, message.isValid);
        break;

      case 'RENEW_TOKEN':
        if (this.errors[correlationId]) {
          const error = this.errors[correlationId];
          delete this.errors[correlationId];
          EventBus.getInstance().emit('ERROR_TOKEN_RENEWED', correlationId, error);
          return;
        }
        EventBus.getInstance().emit('MESSAGE_RECEIVED', message);
        EventBus.getInstance().emit('TOKEN_RENEWED', correlationId, message.accessToken, message.refreshToken);
        break;

      case 'PROCESSES_RETRIEVED': // GET_PROCESSES
        if (this.errors[correlationId]) {
          const error = this.errors[correlationId];
          delete this.errors[correlationId];
          EventBus.getInstance().emit('ERROR_PROCESSES_RETRIEVED', correlationId, error);
          return;
        }
        EventBus.getInstance().emit('PROCESSES_RETRIEVED', correlationId, message.processes);
        break;

      case 'PROFILE_CREATED': // CREATE_PROFILE
        if (this.errors[correlationId]) {
          const error = this.errors[correlationId];
          delete this.errors[correlationId];
          EventBus.getInstance().emit('ERROR_PROFILE_CREATED', correlationId, error);
          return;
        }
        EventBus.getInstance().emit('MESSAGE_RECEIVED', message);
        EventBus.getInstance().emit('PROFILE_CREATED', correlationId, message.profileData);
        break;

      case 'FOLDER_CREATED': // CREATE_FOLDER
        if (this.errors[correlationId]) {
          const error = this.errors[correlationId];
          delete this.errors[correlationId];
          EventBus.getInstance().emit('ERROR_FOLDER_CREATED', correlationId, error);
          return;
        }
        EventBus.getInstance().emit('MESSAGE_RECEIVED', message);
        break;

      case 'DATA_RETRIEVED': // RETRIEVE_DATA
        if (this.errors[correlationId]) {
          const error = this.errors[correlationId];
          delete this.errors[correlationId];
          EventBus.getInstance().emit('ERROR_DATA_RETRIEVED', correlationId, error);
          return;
        }
        EventBus.getInstance().emit('MESSAGE_RECEIVED', message);
        EventBus.getInstance().emit('DATA_RETRIEVED', correlationId, message.data);
        break;

      case 'ERROR':
        console.error('Error:', message);
        this.errors[correlationId] = message.error;
        break;
    }
  }
}