'use strict';

const createBufferReader = require("../buffer-reader");
const roundEven = require("../../round-even");
const createBitParser = require("../../bit-parser");
const decode = require("../decode");

/* File flags: (ref http://wiki.osdev.org/ISO_9660#Directories)
 *   Bit      Description
 *   0        If set, the existence of this file need not be made known to the user (basically a 'hidden' flag.
 *   1        If set, this record describes a directory (in other words, it is a subdirectory extent).
 *   2        If set, this file is an "Associated File".
 *   3        If set, the extended attribute record contains information about the format of this file.
 *   4        If set, owner and group permissions are set in the extended attribute record.
 *   5 & 6    Reserved
 *   7        If set, this is not the final directory record for this file (for files spanning several extents, for example files over 4GiB long.
 */

let parseFileFlags = createBitParser([
    "hidden",
    "directory",
    "associated",
    "inEAR",
    "permissionsInEAR",
    null,
    null,
    "moreRecordsFollowing"
]);

module.exports = function parseDirectoryRecord(data, {encoding} = {encoding: "ascii"}) {
    let bufferReader = createBufferReader(data, {encoding: encoding});

    let identifierLength = bufferReader.int8(32);
    let identifierEnd = roundEven(32 + identifierLength);

    return {
        encoding: encoding,
        recordLength: bufferReader.int8(0),
        extendedAttributeRecordLength: bufferReader.int8(1),
        extentLocation: bufferReader.int32_LSB_MSB(2),
        extentSize: bufferReader.int32_LSB_MSB(10),
        recordingDate: bufferReader.directoryDatetime(18),
        fileFlags: parseFileFlags(bufferReader.int8(25)),
        interleavedUnitSize: bufferReader.int8(26),
        interleavedGapSize: bufferReader.int8(27),
        sequenceNumber: bufferReader.int16_LSB_MSB(28),
        identifierLength: identifierLength,
        identifier: bufferReader.strFilename(33, identifierLength),
        systemUse: data.slice(identifierEnd, 254) // FIXME: Extensions!
    }
};