vk-bridge-level/lib/iterators/key_iterator.js

Level abstraction for VK Bridge

var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) {
    function adopt(value) { return value instanceof P ? value : new P(function (resolve) { resolve(value); }); }
    return new (P || (P = Promise))(function (resolve, reject) {
        function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } }
        function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } }
        function step(result) { result.done ? resolve(result.value) : adopt(result.value).then(fulfilled, rejected); }
        step((generator = generator.apply(thisArg, _arguments || [])).next());
    });
};
import { AbstractKeyIterator } from 'abstract-level';
const ITERATOR_LIMIT = 1000;
export class VkBridgeKeyIterator extends AbstractKeyIterator {
    constructor(db, options) {
        super(db, options);
        this.keys = [];
        this.index = 0;
        this.isEnd = false;
    }
    _next(callback) {
        if (this.needLoadMore()) {
            this.loadKeys(Number.isSafeInteger(this.limit) ? this.limit : ITERATOR_LIMIT)
                .then(() => this.nextInner(callback))
                .catch((e) => this.db.processBridgeError(e, callback));
        }
        else {
            this.nextInner(callback);
        }
    }
    _nextv(size, options, callback) {
        if (this.needLoadMore(size)) {
            this.loadKeys(Math.min(size, ITERATOR_LIMIT))
                .then(() => this.nextInnerMulti(size, callback))
                .catch((e) => this.db.processBridgeError(e, callback));
        }
        else {
            this.nextInnerMulti(size, callback);
        }
    }
    _seek(target, options) {
        const i = this.keys.indexOf(target);
        if (i !== -1) {
            this.index = i;
        }
    }
    loadKeys(count) {
        return __awaiter(this, void 0, void 0, function* () {
            if (this.isEnd) {
                return;
            }
            const { keys } = yield this.db._bridge.send('VKWebAppStorageGetKeys', { offset: this.index, count });
            if (keys.length === 0) {
                this.isEnd = true;
                return;
            }
            this.keys.push(...keys);
        });
    }
    needLoadMore(size = 1) {
        return this.index + size > this.keys.length;
    }
    nextInner(callback) {
        const key = this.keys[this.index];
        this.index++;
        this.db.nextTick(callback, null, key);
    }
    nextInnerMulti(size, callback) {
        const keys = this.keys.slice(this.index, this.index + size);
        this.index += size;
        this.db.nextTick(callback, null, keys);
    }
}