// Copyright 2017-2019 @polkadot/ui-keyring authors & contributors
// This software may be modified and distributed under the terms
// of the Apache-2.0 license. See the LICENSE file for details.

import { KeyringPair, KeyringPair$Meta, KeyringPair$Json } from '@polkadot/keyring/types';
import { KeypairType } from '@polkadot/util-crypto/types';
import { AddressSubject, SingleAddress } from './observable/types';
import { CreateResult, KeyringAddress, KeyringAddressType, KeyringItemType, KeyringJson, KeyringJson$Meta, KeyringOptions, KeyringStruct } from './types';

import createPair from '@polkadot/keyring/pair';
import { hexToU8a, isHex, isString } from '@polkadot/util';

import env from './observable/development';
import Base from './Base';
import { accountKey, addressKey, accountRegex, addressRegex, contractKey, contractRegex } from './defaults';
import keyringOption from './options';

const RECENT_EXPIRY = 24 * 60 * 60;

// No accounts (or test accounts) should be loaded until after the chain determination.
// Chain determination occurs outside of Keyring. Loading `keyring.loadAll({ type: 'ed25519' | 'sr25519' })` is triggered
// from the API after the chain is received
export class Keyring extends Base implements KeyringStruct {
  private stores = {
    address: (): AddressSubject => this.addresses,
    contract: (): AddressSubject => this.contracts,
    account: (): AddressSubject => this.accounts
  };

  public addExternal (address: string | Uint8Array, meta: KeyringPair$Meta = {}): CreateResult {
    const pair = this.keyring.addFromAddress(address, { ...meta, isExternal: true }, null);

    return {
      json: this.saveAccount(pair),
      pair
    };
  }

  public addHardware (address: string | Uint8Array, hardwareType: string, meta: KeyringPair$Meta = {}): CreateResult {
    return this.addExternal(address, { ...meta, hardwareType, isHardware: true });
  }

  public addPair (pair: KeyringPair, password: string): CreateResult {
    this.keyring.addPair(pair);

    return {
      json: this.saveAccount(pair, password),
      pair
    };
  }

  public addUri (suri: string, password?: string, meta: KeyringPair$Meta = {}, type?: KeypairType): CreateResult {
    const pair = this.keyring.addFromUri(suri, meta, type);

    return {
      json: this.saveAccount(pair, password),
      pair
    };
  }

  public backupAccount (pair: KeyringPair, password: string): KeyringPair$Json {
    if (!pair.isLocked) {
      pair.lock();
    }

    pair.decodePkcs8(password);

    return pair.toJson(password);
  }

  public createFromUri (suri: string, meta: KeyringPair$Meta = {}, type?: KeypairType): KeyringPair {
    return this.keyring.createFromUri(suri, meta, type);
  }

  public encryptAccount (pair: KeyringPair, password: string): void {
    const json = pair.toJson(password);

    json.meta.whenEdited = Date.now();

    this.keyring.addFromJson(json);
    this.accounts.add(this._store, pair.address, json);
  }

  public forgetAccount (address: string): void {
    this.keyring.removePair(address);
    this.accounts.remove(this._store, address);
  }

  public forgetAddress (address: string): void {
    this.addresses.remove(this._store, address);
  }

  public forgetContract (address: string): void {
    this.contracts.remove(this._store, address);
  }

  public getAccount (address: string | Uint8Array): KeyringAddress | undefined {
    return this.getAddress(address, 'account');
  }

  public getAccounts (): KeyringAddress[] {
    const available = this.accounts.subject.getValue();

    return Object
      .keys(available)
      .map((address): KeyringAddress => this.getAddress(address, 'account') as KeyringAddress)
      .filter((account): boolean => env.isDevelopment() || account.meta.isTesting !== true);
  }

  public getAddress (_address: string | Uint8Array, type: KeyringItemType | null = null): KeyringAddress | undefined {
    const address = isString(_address)
      ? _address
      : this.encodeAddress(_address);
    const publicKey = this.decodeAddress(address);
    const stores = type
      ? [this.stores[type]]
      : Object.values(this.stores);

    const info = stores.reduce<SingleAddress | undefined>((lastInfo, store): SingleAddress | undefined =>
      (store().subject.getValue()[address] || lastInfo), undefined);

    return info && {
      address,
      publicKey,
      meta: info.json.meta
    };
  }

  public getAddresses (): KeyringAddress[] {
    const available = this.addresses.subject.getValue();

    return Object
      .keys(available)
      .map((address): KeyringAddress => this.getAddress(address) as KeyringAddress);
  }

  public getContract (address: string | Uint8Array): KeyringAddress | undefined {
    return this.getAddress(address, 'contract');
  }

  public getContracts (): KeyringAddress[] {
    const available = this.contracts.subject.getValue();

    return Object
      .entries(available)
      .filter(([, { json: { meta: { contract } } }]): boolean =>
        !!contract && contract.genesisHash === this.genesisHash
      )
      .map(([address]): KeyringAddress => this.getContract(address) as KeyringAddress);
  }

  private rewriteKey (json: KeyringJson, key: string, hexAddr: string, creator: (addr: string) => string): void {
    if (hexAddr.substr(0, 2) === '0x') {
      return;
    }

    this._store.remove(key);
    this._store.set(creator(hexAddr), json);
  }

  private loadAccount (json: KeyringJson, key: string): void {
    if (!json.meta.isTesting && (json as KeyringPair$Json).encoded) {
      // FIXME Just for the transition period (ignoreChecksum)
      const pair = this.keyring.addFromJson(json as KeyringPair$Json, true);

      this.accounts.add(this._store, pair.address, json);
    }

    const [, hexAddr] = key.split(':');

    this.rewriteKey(json, key, hexAddr.trim(), accountKey);
  }

  private loadAddress (json: KeyringJson, key: string): void {
    const { isRecent, whenCreated = 0 } = json.meta;

    if (isRecent && (Date.now() - whenCreated) > RECENT_EXPIRY) {
      this._store.remove(key);
      return;
    }

    const address = this.encodeAddress(
      isHex(json.address)
        ? hexToU8a(json.address)
        // FIXME Just for the transition period (ignoreChecksum)
        : this.decodeAddress(json.address, true)
    );
    const [, hexAddr] = key.split(':');

    this.addresses.add(this._store, address, json);
    this.rewriteKey(json, key, hexAddr, addressKey);
  }

  private loadContract (json: KeyringJson, key: string): void {
    const address = this.encodeAddress(
      this.decodeAddress(json.address)
    );
    const [, hexAddr] = key.split(':');

    // move genesisHash to top-level (TODO Remove from contracts section?)
    json.meta.genesisHash = json.meta.genesisHash || (json.meta.contract && json.meta.contract.genesisHash);

    this.contracts.add(this._store, address, json);
    this.rewriteKey(json, key, hexAddr, contractKey);
  }

  private loadInjected (address: string, meta: KeyringJson$Meta): void {
    const json = {
      address,
      meta: {
        ...meta,
        isInjected: true
      }
    };
    const pair = this.keyring.addFromAddress(address, json.meta);

    this.accounts.add(this._store, pair.address, json);
  }

  private allowGenesis (json?: KeyringJson | { meta: KeyringJson$Meta } | null): boolean {
    if (json && json.meta && this.genesisHash) {
      if (json.meta.genesisHash) {
        return this.genesisHash === json.meta.genesisHash;
      } else if (json.meta.contract) {
        return this.genesisHash === json.meta.contract.genesisHash;
      }
    }

    return true;
  }

  public loadAll (options: KeyringOptions, injected: { address: string; meta: KeyringJson$Meta }[] = []): void {
    super.initKeyring(options);

    this._store.all((key: string, json: KeyringJson): void => {
      if (options.filter ? options.filter(json) : true) {
        if (this.allowGenesis(json)) {
          if (accountRegex.test(key)) {
            this.loadAccount(json, key);
          } else if (addressRegex.test(key)) {
            this.loadAddress(json, key);
          } else if (contractRegex.test(key)) {
            this.loadContract(json, key);
          }
        }
      }
    });

    injected.forEach((account): void => {
      if (this.allowGenesis(account)) {
        this.loadInjected(account.address, account.meta);
      }
    });

    keyringOption.init(this);
  }

  public restoreAccount (json: KeyringPair$Json, password: string): KeyringPair {
    const type = Array.isArray(json.encoding.content) ? json.encoding.content[1] : 'ed25519';
    const pair = createPair(
      type,
      {
        // FIXME Just for the transition period (ignoreChecksum)
        publicKey: this.decodeAddress(json.address, true)
      },
      json.meta,
      hexToU8a(json.encoded)
    );

    // unlock, save account and then lock (locking cleans secretKey, so needs to be last)
    pair.decodePkcs8(password);
    this.addPair(pair, password);
    pair.lock();

    return pair;
  }

  public saveAccount (pair: KeyringPair, password?: string): KeyringPair$Json {
    this.addTimestamp(pair);

    const json = pair.toJson(password);

    this.keyring.addFromJson(json);
    this.accounts.add(this._store, pair.address, json);

    return json;
  }

  public saveAccountMeta (pair: KeyringPair, meta: KeyringPair$Meta): void {
    const address = pair.address;

    this._store.get(accountKey(address), (json: KeyringJson): void => {
      pair.setMeta(meta);
      json.meta = pair.meta;

      this.accounts.add(this._store, address, json);
    });
  }

  public saveAddress (address: string, meta: KeyringPair$Meta, type: KeyringAddressType = 'address'): KeyringPair$Json {
    const available = this.addresses.subject.getValue();

    const json = (available[address] && available[address].json) || {
      address,
      meta: {
        isRecent: undefined,
        whenCreated: Date.now()
      }
    };

    Object.keys(meta).forEach((key): void => {
      json.meta[key] = meta[key];
    });

    delete json.meta.isRecent;

    this.stores[type]().add(this._store, address, json);

    return json as KeyringPair$Json;
  }

  public saveContract (address: string, meta: KeyringPair$Meta): KeyringPair$Json {
    return this.saveAddress(address, meta, 'contract');
  }

  public saveRecent (address: string): SingleAddress {
    const available = this.addresses.subject.getValue();

    if (!available[address]) {
      this.addresses.add(this._store, address, {
        address,
        meta: {
          genesisHash: this.genesisHash,
          isRecent: true,
          whenCreated: Date.now()
        }
      });
    }

    return this.addresses.subject.getValue()[address];
  }
}

const keyringInstance = new Keyring();

export default keyringInstance;