import { PublicKey, Connection } from '@solana/web3.js';
import BN from 'bn.js'; // eslint-disable-line @typescript-eslint/no-unused-vars
import * as borsh from '@project-serum/borsh'; // eslint-disable-line @typescript-eslint/no-unused-vars
import * as types from '../types'; // eslint-disable-line @typescript-eslint/no-unused-vars
import { WHIRLPOOL_PROGRAM_ID } from '../programId';

export interface WhirlpoolsConfigFields {
  feeAuthority: PublicKey;
  collectProtocolFeesAuthority: PublicKey;
  rewardEmissionsSuperAuthority: PublicKey;
  defaultProtocolFeeRate: number;
}

export interface WhirlpoolsConfigJSON {
  feeAuthority: string;
  collectProtocolFeesAuthority: string;
  rewardEmissionsSuperAuthority: string;
  defaultProtocolFeeRate: number;
}

export class WhirlpoolsConfig {
  readonly feeAuthority: PublicKey;
  readonly collectProtocolFeesAuthority: PublicKey;
  readonly rewardEmissionsSuperAuthority: PublicKey;
  readonly defaultProtocolFeeRate: number;

  static readonly discriminator = Buffer.from([157, 20, 49, 224, 217, 87, 193, 254]);

  static readonly layout = borsh.struct([
    borsh.publicKey('feeAuthority'),
    borsh.publicKey('collectProtocolFeesAuthority'),
    borsh.publicKey('rewardEmissionsSuperAuthority'),
    borsh.u16('defaultProtocolFeeRate'),
  ]);

  constructor(fields: WhirlpoolsConfigFields) {
    this.feeAuthority = fields.feeAuthority;
    this.collectProtocolFeesAuthority = fields.collectProtocolFeesAuthority;
    this.rewardEmissionsSuperAuthority = fields.rewardEmissionsSuperAuthority;
    this.defaultProtocolFeeRate = fields.defaultProtocolFeeRate;
  }

  static async fetch(c: Connection, address: PublicKey): Promise<WhirlpoolsConfig | null> {
    const info = await c.getAccountInfo(address);

    if (info === null) {
      return null;
    }
    if (!info.owner.equals(WHIRLPOOL_PROGRAM_ID)) {
      throw new Error("account doesn't belong to this program");
    }

    return this.decode(info.data);
  }

  static async fetchMultiple(c: Connection, addresses: PublicKey[]): Promise<Array<WhirlpoolsConfig | null>> {
    const infos = await c.getMultipleAccountsInfo(addresses);

    return infos.map((info) => {
      if (info === null) {
        return null;
      }
      if (!info.owner.equals(WHIRLPOOL_PROGRAM_ID)) {
        throw new Error("account doesn't belong to this program");
      }

      return this.decode(info.data);
    });
  }

  static decode(data: Buffer): WhirlpoolsConfig {
    if (!data.slice(0, 8).equals(WhirlpoolsConfig.discriminator)) {
      throw new Error('invalid account discriminator');
    }

    const dec = WhirlpoolsConfig.layout.decode(data.slice(8));

    return new WhirlpoolsConfig({
      feeAuthority: dec.feeAuthority,
      collectProtocolFeesAuthority: dec.collectProtocolFeesAuthority,
      rewardEmissionsSuperAuthority: dec.rewardEmissionsSuperAuthority,
      defaultProtocolFeeRate: dec.defaultProtocolFeeRate,
    });
  }

  toJSON(): WhirlpoolsConfigJSON {
    return {
      feeAuthority: this.feeAuthority.toString(),
      collectProtocolFeesAuthority: this.collectProtocolFeesAuthority.toString(),
      rewardEmissionsSuperAuthority: this.rewardEmissionsSuperAuthority.toString(),
      defaultProtocolFeeRate: this.defaultProtocolFeeRate,
    };
  }

  static fromJSON(obj: WhirlpoolsConfigJSON): WhirlpoolsConfig {
    return new WhirlpoolsConfig({
      feeAuthority: new PublicKey(obj.feeAuthority),
      collectProtocolFeesAuthority: new PublicKey(obj.collectProtocolFeesAuthority),
      rewardEmissionsSuperAuthority: new PublicKey(obj.rewardEmissionsSuperAuthority),
      defaultProtocolFeeRate: obj.defaultProtocolFeeRate,
    });
  }
}