mp3tag/out/dataSource.js

A library for reading/writing mp3 tag data

"use strict";
/** This module defines the DataSource class, which represents
 *  data, which hasn't been yet loaded into a buffer.
 */
Object.defineProperty(exports, "__esModule", { value: true });
exports.DataSource = void 0;
const data_1 = require("./data");
const file_1 = require("./file");
class DataSource {
    source;
    offset;
    size;
    /** Constructs the data source from a file and optional offset and length.
     *
     * @param sourceFile a File where the data should be read from
     * @param offset the offset, where the data starts (default: 0)
     * @param size the length of the data block (default: sourceFile.size-offset)
     */
    constructor(sourceFile, offset, size) {
        if (!(sourceFile instanceof file_1.File)) {
            throw new Error("source must be a File");
        }
        this.source = sourceFile;
        this.offset = offset ?? 0;
        this.size = size ?? (this.source.size - this.offset);
    }
    /** Converts the DataSource into a Data object. This works asynchronously, as it
     *  has to read the content from the file
     */
    async toData() {
        const buffer = await this.source.readSlice(this.offset, this.size);
        return new data_1.Data(buffer);
    }
    toString() {
        return "DataSource:[offset:" + this.offset + ",size:" + this.size + "]@File";
    }
}
exports.DataSource = DataSource;