@adguard/agtree/dist/serializer/misc/domain-list-serializer.js

Tool set for working with adblock filter lists

/*
 * AGTree v3.2.2 (build date: Tue, 08 Jul 2025 13:39:47 GMT)
 * (c) 2025 Adguard Software Ltd.
 * Released under the MIT license
 * https://github.com/AdguardTeam/tsurlfilter/tree/master/packages/agtree#readme
 */
import { NULL, COMMA, PIPE } from '../../utils/constants.js';
import { isUndefined } from '../../utils/type-guards.js';
import { BaseSerializer } from '../base-serializer.js';
import { ListItemsSerializer } from './list-items-serializer.js';
import { DomainListMarshallingMap } from '../../marshalling-utils/misc/domain-list-common.js';
import { BinaryTypeMarshallingMap } from '../../marshalling-utils/misc/binary-type-common.js';

/**
 * Value map for binary serialization. This helps to reduce the size of the serialized data,
 * as it allows us to use a single byte to represent frequently used values.
 *
 * ! IMPORTANT: If you change values here, please update the {@link BINARY_SCHEMA_VERSION}!
 *
 * @note Only 256 values can be represented this way.
 */
const SEPARATOR_SERIALIZATION_MAP = new Map([
    [COMMA, 0],
    [PIPE, 1],
]);
/**
 * `DomainListSerializer` is responsible for serializing a domain list.
 *
 * @example
 * - If the rule is `example.com,~example.net##.ads`, the domain list is `example.com,~example.net`.
 * - If the rule is `ads.js^$script,domains=example.com|~example.org`, the domain list is `example.com|~example.org`.
 * This serializer is responsible for serializing these domain lists.
 * @see {@link https://help.eyeo.com/adblockplus/how-to-write-filters#elemhide_domains}
 */
class DomainListSerializer extends BaseSerializer {
    /**
     * Serializes a domain list node to binary format.
     *
     * @param node Node to serialize.
     * @param buffer ByteBuffer for writing binary data.
     */
    static serialize(node, buffer) {
        buffer.writeUint8(BinaryTypeMarshallingMap.DomainListNode);
        const separator = SEPARATOR_SERIALIZATION_MAP.get(node.separator);
        if (isUndefined(separator)) {
            throw new Error(`Invalid separator: ${node.separator}`);
        }
        buffer.writeUint8(DomainListMarshallingMap.Separator);
        buffer.writeUint8(separator);
        buffer.writeUint8(DomainListMarshallingMap.Children);
        ListItemsSerializer.serialize(node.children, buffer);
        if (!isUndefined(node.start)) {
            buffer.writeUint8(DomainListMarshallingMap.Start);
            buffer.writeUint32(node.start);
        }
        if (!isUndefined(node.end)) {
            buffer.writeUint8(DomainListMarshallingMap.End);
            buffer.writeUint32(node.end);
        }
        buffer.writeUint8(NULL);
    }
}

export { DomainListSerializer };