'use strict';

const Promise = require("bluebird");

const parsePathTable = require("../parse/path-table");

module.exports = function readPathTable(image) {
    return Promise.try(() => {
        return image.getPrimaryVolumeDescriptor();
    }).then((primaryVolumeDescriptor) => {
        return Promise.try(() => {
            let start = primaryVolumeDescriptor.data.pathTableLocationL * primaryVolumeDescriptor.data.sectorSize;
            let end = start + primaryVolumeDescriptor.data.pathTableSize - 1;

            return image.readRange(start, end);
        }).then((buffer) => {
            return parsePathTable(buffer, primaryVolumeDescriptor.data.sectorSize);
        });
    });
}