// import { WebSocketClient } from '../websockets';
import { INotification } from '~/models/notification.model';
import { IProcess } from '~/models/process.model';
// import Database from './database';
import { initWebsocket, sendMessage } from '../websockets';
import { ApiReturn, Member, Process, RoleDefinition, UserDiff } from '../../pkg/sdk_client';
import ModalService from './modal.service';
import Database from './database.service';
import { storeData, retrieveData } from './storage.service';

export const U32_MAX = 4294967295;

const storageUrl = `http://localhost:8080`;
const BOOTSTRAPURL = [`http://localhost:8090`];

export default class Services {
  private static initializing: Promise<Services> | null = null;
  private static instance: Services;
  private currentProcess: string | null = null;
  private pendingUpdates: any | null = null;
  private currentUpdateMerkleRoot: string | null = null;
  private localAddress: string | null = null;
  private pairedAddresses: string[] = [];
  private sdkClient: any;
  private processes: IProcess[] | null = null;
  private notifications: any[] | null = null;
  private subscriptions: { element: Element; event: string; eventHandler: string }[] = [];
  private database: any;
  private routingInstance!: ModalService;
  private relayAddresses: { [wsurl: string]: string } = {};
  // Private constructor to prevent direct instantiation from outside
  private constructor() {}

  // Method to access the singleton instance of Services
  public static async getInstance(): Promise<Services> {
    if (Services.instance) {
      return Services.instance;
    }

    if (!Services.initializing) {
      Services.initializing = (async () => {
        const instance = new Services();
        await instance.init();
        instance.routingInstance = await ModalService.getInstance();
        return instance;
      })();
    }

    console.log('initializing services');
    Services.instance = await Services.initializing;
    Services.initializing = null; // Reset for potential future use
    return Services.instance;
  }

  public async init(): Promise<void> {
    this.notifications = this.getNotifications();
    this.sdkClient = await import('../../pkg/sdk_client');
    this.sdkClient.setup();
    for (const wsurl of Object.values(BOOTSTRAPURL)) {
      this.updateRelay(wsurl, '');
    }
    await this.connectAllRelays();
  }

  /**
   * Calls `this.addWebsocketConnection` for each `wsurl` in relayAddresses.
   */
  public async connectAllRelays(): Promise<void> {
      for (const wsurl of Object.keys(this.relayAddresses)) {
          try {
              console.log(`Connecting to: ${wsurl}`);
              await this.addWebsocketConnection(wsurl);
              console.log(`Successfully connected to: ${wsurl}`);
          } catch (error) {
              console.error(`Failed to connect to ${wsurl}:`, error);
          }
      }
  }

  public async addWebsocketConnection(url: string): Promise<void> {
    console.log('Opening new websocket connection');
    await initWebsocket(url);
  }

  /**
   * Add or update a key/value pair in relayAddresses.
   * @param wsurl - The WebSocket URL (key).
   * @param spAddress - The SP Address (value).
   */
  public updateRelay(wsurl: string, spAddress: string): void {
      this.relayAddresses[wsurl] = spAddress;
      console.log(`Updated: ${wsurl} -> ${spAddress}`);
  }

  /**
   * Retrieve the spAddress for a given wsurl.
   * @param wsurl - The WebSocket URL to look up.
   * @returns The SP Address if found, or undefined if not.
   */
  public getSpAddress(wsurl: string): string | undefined {
      return this.relayAddresses[wsurl];
  }

  /**
   * Get all key/value pairs from relayAddresses.
   * @returns An array of objects containing wsurl and spAddress.
   */
  public getAllRelays(): { wsurl: string; spAddress: string }[] {
      return Object.entries(this.relayAddresses).map(([wsurl, spAddress]) => ({
          wsurl,
          spAddress,
      }));
  }

  /**
   * Print all key/value pairs for debugging.
   */
  public printAllRelays(): void {
      console.log("Current relay addresses:");
      for (const [wsurl, spAddress] of Object.entries(this.relayAddresses)) {
          console.log(`${wsurl} -> ${spAddress}`);
      }
  }

  public isPaired(): boolean {
    try {
      return this.sdkClient.is_paired();
    } catch (e) {
      throw new Error(`isPaired ~ Error: ${e}`);
    }
  }

  public async unpairDevice(): Promise<void> {
    try {
      this.sdkClient.unpair_device();
      const newDevice = this.dumpDeviceFromMemory();
      await this.saveDeviceInDatabase(newDevice);
    } catch (e) {
      throw new Error(`Failed to unpair device: ${e}`);
    }
  }

  public async getSecretForAddress(address: string): Promise<string | null> {
    const db = await Database.getInstance();
    return await db.getObject('shared_secrets', address);
  }

  public async connectMember(members: Member[]): Promise<ApiReturn> {
    if (members.length === 0) {
      throw new Error('Trying to connect to empty members list');
    }

    const members_str = members.map((member) => JSON.stringify(member));

    const waitForAmount = async (): Promise<BigInt> => {
      let attempts = 3;
      while (attempts > 0) {
        const amount = this.getAmount();
        if (amount !== 0n) {
          return amount;
        }
        attempts--;
        if (attempts > 0) {
          await new Promise((resolve) => setTimeout(resolve, 1000)); // Wait for 1 second
        }
      }
      throw new Error('Amount is still 0 after 3 attempts');
    };

    let availableAmt = this.getAmount();
    if (availableAmt === 0n) {
      const faucetMsg = this.createFaucetMessage();
      this.sendFaucetMessage(faucetMsg);

      try {
        availableAmt = await waitForAmount();
      } catch (e) {
        console.error('Failed to retrieve amount:', e);
        throw e; // Rethrow the error if needed
      }
    }

    try {
      return this.sdkClient.create_connect_transaction(members_str, 1);
    } catch (e) {
      throw e;
    }
  }

  public async createPairingProcess(pairWith: string[], relayAddress: string, feeRate: number): Promise<ApiReturn> {
    if (this.sdkClient.is_paired()) {
      throw new Error('Device already paired');
    }
    const myAddress: string = this.sdkClient.get_address();
    pairWith.push(myAddress);
    const newKey = this.sdkClient.get_new_keypair();
    const pairingTemplate = {
      description: 'pairing',
      roles: {
        owner: {
          members: [{ sp_addresses: pairWith }],
          validation_rules: [
            {
              quorum: 1.0,
              fields: ['description', 'roles', 'session_privkey', 'session_pubkey', 'key_parity'],
              min_sig_member: 1.0,
            },
          ],
          storages: [storageUrl]
        },
      },
      session_privkey: newKey['private_key'],
      session_pubkey: newKey['x_only_public_key'],
      key_parity: newKey['key_parity'],
    };
    try {
      return this.sdkClient.create_new_process(JSON.stringify(pairingTemplate), null, relayAddress, feeRate); 
    } catch (e) {
      throw new Error(`Creating process failed:, ${e}`);
    }
  }

  // Create prd update for current process and update
  public createPrdUpdate(pcdMerkleRoot: string): ApiReturn {
    if (!this.currentProcess) {
      throw new Error('No current process defined');
    }

    try {
      return this.sdkClient.create_update_message(this.currentProcess, pcdMerkleRoot);
    } catch (e) {
      throw new Error(`Failed to create prd update: ${e}`);
    }
  }

  public createPrdResponse(pcdMerkleRoot: string): ApiReturn {
    if (!this.currentProcess) {
      throw new Error('No current process defined');
    }

    try {
      return this.sdkClient.create_response_prd(this.currentProcess, pcdMerkleRoot);
    } catch (e) {
      throw e;
    }
  }

  public approveChange(currentPcdMerkleRoot: string): ApiReturn {
    if (!this.currentProcess) {
      throw new Error('No current process defined');
    }

    try {
      return this.sdkClient.validate_state(this.currentProcess, currentPcdMerkleRoot);
    } catch (e) {
      throw new Error(`Failed to create prd response: ${e}`);
    }
  }

  public rejectChange(): ApiReturn {
    if (!this.currentProcess || !this.currentUpdateMerkleRoot) {
      throw new Error('No current process and/or current update defined');
    }

    try {
      return this.sdkClient.refuse_state(this.currentProcess, this.currentUpdateMerkleRoot);
    } catch (e) {
      throw new Error(`Failed to create prd response: ${e}`);
    }
  }

  async resetDevice() {
    await this.sdkClient.reset_device();
  }

  async sendNewTxMessage(message: string) {
    sendMessage('NewTx', message);
  }

  async sendCommitMessage(message: string) {
    sendMessage('Commit', message);
  }

  async sendCipherMessages(ciphers: string[]) {
    for (let i = 0; i < ciphers.length; i++) {
      const cipher = ciphers[i];
      sendMessage('Cipher', cipher);
    }
  }

  sendFaucetMessage(message: string): void {
    sendMessage('Faucet', message);
  }

  async parseCipher(message: string) {
    try {
      // console.log('parsing new cipher');
      const apiReturn = this.sdkClient.parse_cipher(message);
      console.log('🚀 ~ Services ~ parseCipher ~ apiReturn:', apiReturn);
      await this.handleApiReturn(apiReturn);
    } catch (e) {
      console.error(`Parsed cipher with error: ${e}`);
    }
    // await this.saveCipherTxToDb(parsedTx)
  }

  async parseNewTx(tx: string) {
    try {
      const parsedTx = this.sdkClient.parse_new_tx(tx, 0);
      if (parsedTx) {
        try {
          await this.handleApiReturn(parsedTx);
          const newDevice = this.dumpDeviceFromMemory();
          await this.saveDeviceInDatabase(newDevice);
        } catch (e) {
          console.error('Failed to update device with new tx');
        }
      }
    } catch (e) {
      console.trace(e);
    }
  }

  public async handleApiReturn(apiReturn: ApiReturn) {
    if (apiReturn.new_tx_to_send && apiReturn.new_tx_to_send.transaction.length != 0) {
      await this.sendNewTxMessage(JSON.stringify(apiReturn.new_tx_to_send));
    }

    if (apiReturn.secrets) {
      const unconfirmedSecrets = apiReturn.secrets.unconfirmed_secrets;
      const confirmedSecrets = apiReturn.secrets.shared_secrets;

      const db = await Database.getInstance();
      for (const secret of unconfirmedSecrets) {
        await db.addObject({
          storeName: 'unconfirmed_secrets',
          object: secret,
          key: null,
        });
      }
      const entries = Object.entries(confirmedSecrets).map(([key, value]) => ({ key, value }));
      for (const entry of entries) {
        try {
          await db.addObject({
            storeName: 'shared_secrets',
            object: entry.value,
            key: entry.key,
          });
        } catch (e) {
          throw e;
        }

        // We don't want to throw an error, it could simply be that we registered directly the shared secret
        // this.removeUnconfirmedSecret(entry.value);
      }
    }

    setTimeout(async () => {
      if (apiReturn.updated_process) {
        const updatedProcess = apiReturn.updated_process;

        // Save process to storage
        try {
          await this.saveProcess(updatedProcess.commitment_tx, updatedProcess.current_process);
        } catch (e) {
          throw e;
        }

        if (updatedProcess.new_diffs.length != 0) {
          try {
            this.saveDiffs(updatedProcess.new_diffs);
          } catch (e) {
            throw e;
          }
        }

        if (updatedProcess.modified_state) {
          // For now it can only mean we added a validation token to an existing state
          // Not sure what action to take
        }
      }

      if (apiReturn.commit_to_send) {
        const commit = apiReturn.commit_to_send;
        await this.sendCommitMessage(JSON.stringify(commit));
      }

      if (apiReturn.ciphers_to_send && apiReturn.ciphers_to_send.length != 0) {
        await this.sendCipherMessages(apiReturn.ciphers_to_send);
      }
    }, 0);
  }

  public async evaluatePendingUpdates() {
    if (!this.currentProcess) {
      throw new Error('No current process');
    }

    try {
      await this.openConfirmationModal();
    } catch (e) {
      throw new Error(`Error while evaluating pending updates for process ${this.currentProcess}: ${e}`);
    }
  }

  private async openConfirmationModal() {
    if (!this.pendingUpdates || this.pendingUpdates.modified_values.length === 0) {
      console.log('No pending updates to validate');
    }

    for (const value of this.pendingUpdates!.modified_values) {
      if (value.notify_user) {
        // TODO notification pop up
      }
      if (!value.need_validation) {
        continue;
      }
      if (value.proof) {
        // It seems we already validated that, check the proof and if valid just notify user
        continue;
      }
      const actualProposal: Record<string, RoleDefinition> = JSON.parse(value.new_value);
      const merkleRoot: string = value.new_state_merkle_root;
      try {
        await this.routingInstance.openPairingConfirmationModal(actualProposal, this.currentProcess!, merkleRoot);
      } catch (e) {
        throw new Error(`${e}`);
      }
    }
  }

  pairDevice(spAddressList: string[]) {
    if (this.currentProcess) {
      try {
        this.sdkClient.pair_device(this.currentProcess, spAddressList);
      } catch (e) {
        throw new Error(`Failed to pair device: ${e}`);
      }
    }
  }

  public getAmount(): BigInt {
    const amount = this.sdkClient.get_available_amount();
    return amount;
  }

  async getDeviceAddress() {
    return await this.sdkClient.get_address();
  }

  public dumpDeviceFromMemory(): string {
    try {
      return this.sdkClient.dump_device();
    } catch (e) {
      throw new Error(`Failed to dump device: ${e}`);
    }
  }

  async saveDeviceInDatabase(device: any): Promise<void> {
    const db = await Database.getInstance();
    const walletStore = 'wallet';
    try {
      const prevDevice = await this.getDeviceFromDatabase();
      if (prevDevice) {
        await db.deleteObject(walletStore, "1");
      }
      await db.addObject({
        storeName: walletStore,
        object: { pre_id: '1', device },
        key: null,
      });
    } catch (e) {
      console.error(e);
    }
  }

  async getDeviceFromDatabase(): Promise<string | null> {
    const db = await Database.getInstance();
    const walletStore = 'wallet';
    try {
      const dbRes = await db.getObject(walletStore, '1');
      if (dbRes) {
        const wallet = dbRes['device'];
        return wallet;
      } else {
        return null;
      }
    } catch (e) {
      throw new Error(`Failed to retrieve device from db: ${e}`);
    }
  }

  async dumpWallet() {
    const wallet = await this.sdkClient.dump_wallet();
    console.log('🚀 ~ Services ~ dumpWallet ~ wallet:', wallet);
    return wallet;
  }

  public createFaucetMessage() {
    const message = this.sdkClient.create_faucet_msg();
    console.log('🚀 ~ Services ~ createFaucetMessage ~ message:', message);
    return message;
  }

  async createNewDevice() {
    let spAddress = '';
    try {
      spAddress = await this.sdkClient.create_new_device(0, 'regtest');
      const device = this.dumpDeviceFromMemory();
      console.log('🚀 ~ Services ~ device:', device);
      await this.saveDeviceInDatabase(device);
    } catch (e) {
      console.error('Services ~ Error:', e);
    }

    return spAddress;
  }

  async restoreDevice(device: string) {
    try {
      await this.sdkClient.restore_device(device);
      const spAddress = this.sdkClient.get_address();
    } catch (e) {
      console.error(e);
    }
  }

  public async saveProcess(commitedIn: string, process: Process) {
    const db = await Database.getInstance();
    try {
      await db.addObject({
        storeName: 'processes',
        object: process,
        key: commitedIn,
      });
    } catch (e) {
      throw new Error(`Failed to save process: ${e}`);
    }

    // We check how many copies in storage nodes
    // We check the storage nodes in the process itself
    // this.sdkClient.get_storages(commitedIn);
    const storages = [storageUrl];

    for (const state of process.states) {
      if (state.merkle_root === "") {
        continue;
      }
      if (!state.encrypted_pcd) {
        console.warn('Empty encrypted pcd, skipping...');
        continue;
      } 
      for (const [field, hash] of Object.entries(state.pcd_commitment)) { 
        // get the encrypted value with the field name
        const value = state.encrypted_pcd[field]; 
        await storeData(storages, hash, value, null);
      }
    }
  }

  public async fetchValueFromStorage(hash: string): Promise<any | null> {
    const storages = [storageUrl];

    return await retrieveData(storages, hash);
  }

  public async saveDiffs(diffs: UserDiff[]) {
    const db = await Database.getInstance();
    try {
      for (const diff of diffs) {
        await db.addObject({
          storeName: 'diffs',
          object: diff,
          key: null,
        });
      }
    } catch (e) {
      throw new Error(`Failed to save process: ${e}`);
    }
  }

  public async getProcess(commitedIn: string): Promise<Process> {
    const db = await Database.getInstance();
    return await db.getObject('processes', commitedIn);
  }

  public async getProcesses(): Promise<Record<string, Process>> {
    const db = await Database.getInstance();

    const processes: Record<string, Process> = await db.dumpStore('processes');
    return processes;
  }

  // Restore process in wasm with persistent storage
  public async restoreProcesses() {
    const db = await Database.getInstance();
    try {
      const processes: Record<string, Process> = await db.dumpStore('processes');
      if (processes && Object.keys(processes).length != 0) {
        console.log(`Restoring ${Object.keys(processes).length} processes`);
        this.sdkClient.set_process_cache(JSON.stringify(processes));
      } else {
        console.log('No processes to restore!');
      }
    } catch (e) {
      throw e;
    }
  }

  public async restoreSecrets() {
    const db = await Database.getInstance();
    try {
      const sharedSecrets: Record<string, string> = await db.dumpStore('shared_secrets');
      const unconfirmedSecrets = await db.dumpStore('unconfirmed_secrets');
      const secretsStore = {
        shared_secrets: sharedSecrets,
        unconfirmed_secrets: Object.values(unconfirmedSecrets),
      };
      this.sdkClient.set_shared_secrets(JSON.stringify(secretsStore));
    } catch (e) {
      throw e;
    }
  }

  getNotifications(): any[] | null {
    // return [
    //   {
    //     id: 1,
    //     title: 'Notif 1',
    //     description: 'A normal notification',
    //     sendToNotificationPage: false,
    //     path: '/notif1',
    //   },
    //   {
    //     id: 2,
    //     title: 'Notif 2',
    //     description: 'A normal notification',
    //     sendToNotificationPage: false,
    //     path: '/notif2',
    //   },
    //   {
    //     id: 3,
    //     title: 'Notif 3',
    //     description: 'A normal notification',
    //     sendToNotificationPage: false,
    //     path: '/notif3',
    //   },
    // ];
    return this.notifications;
  }

  setNotifications(notifications: any[]) {
    this.notifications = notifications;
  }

  async importJSON(content: any): Promise<void> {
    return Promise.resolve();
  }
}