/*
 * Copyright (c) Huawei Technologies Co., Ltd. 2022-2024. All rights reserved.
 */
package zip4cj.crypto.engine

let CRC_TABLE: Array<Int32> = [0, 1996959894, -301047508, -1727442502, 124634137, 1886057615, -379345611, -1637575261,
249268274, 2044508324, -522852066, -1747789432, 162941995, 2125561021, -407360249, -1866523247, 498536548, 1789927666,
-205950648, -2067906082, 450548861, 1843258603, -187386543, -2083289657, 325883990, 1684777152, -43845254, -1973040660,
335633487, 1661365465, -99664541, -1928851979, 997073096, 1281953886, -715111964, -1570279054, 1006888145, 1258607687,
-770865667, -1526024853, 901097722, 1119000684, -608450090, -1396901568, 853044451, 1172266101, -589951537, -1412350631,
651767980, 1373503546, -925412992, -1076862698, 565507253, 1454621731, -809855591, -1195530993, 671266974, 1594198024,
-972236366, -1324619484, 795835527, 1483230225, -1050600021, -1234817731, 1994146192, 31158534, -1731059524, -271249366,
1907459465, 112637215, -1614814043, -390540237, 2013776290, 251722036, -1777751922, -519137256, 2137656763, 141376813,
-1855689577, -429695999, 1802195444, 476864866, -2056965928, -228458418, 1812370925, 453092731, -2113342271, -183516073,
1706088902, 314042704, -1950435094, -54949764, 1658658271, 366619977, -1932296973, -69972891, 1303535960, 984961486,
-1547960204, -725929758, 1256170817, 1037604311, -1529756563, -740887301, 1131014506, 879679996, -1385723834,
-631195440, 1141124467, 855842277, -1442165665, -586318647, 1342533948, 654459306, -1106571248, -921952122, 1466479909,
544179635, -1184443383, -832445281, 1591671054, 702138776, -1328506846, -942167884, 1504918807, 783551873, -1212326853,
-1061524307, -306674912, -1698712650, 62317068, 1957810842, -355121351, -1647151185, 81470997, 1943803523, -480048366,
-1805370492, 225274430, 2053790376, -468791541, -1828061283, 167816743, 2097651377, -267414716, -2029476910, 503444072,
1762050814, -144550051, -2140837941, 426522225, 1852507879, -19653770, -1982649376, 282753626, 1742555852, -105259153,
-1900089351, 397917763, 1622183637, -690576408, -1580100738, 953729732, 1340076626, -776247311, -1497606297, 1068828381,
1219638859, -670225446, -1358292148, 906185462, 1090812512, -547295293, -1469587627, 829329135, 1181335161, -882789492,
-1134132454, 628085408, 1382605366, -871598187, -1156888829, 570562233, 1426400815, -977650754, -1296233688, 733239954,
1555261956, -1026031705, -1244606671, 752459403, 1541320221, -1687895376, -328994266, 1969922972, 40735498, -1677130071,
-351390145, 1913087877, 83908371, -1782625662, -491226604, 2075208622, 213261112, -1831694693, -438977011, 2094854071,
198958881, -2032938284, -237706686, 1759359992, 534414190, -2118248755, -155638181, 1873836001, 414664567, -2012718362,
-15766928, 1711684554, 285281116, -1889165569, -127750551, 1634467795, 376229701, -1609899400, -686959890, 1308918612,
956543938, -1486412191, -799009033, 1231636301, 1047427035, -1362007478, -640263460, 1088359270, 936918000, -1447252397,
-558129467, 1202900863, 817233897, -1111625188, -893730166, 1404277552, 615818150, -1160759803, -841546093, 1423857449,
601450431, -1285129682, -1000256840, 1567103746, 711928724, -1274298825, -1022587231, 1510334235, 755167117]
public class ZipCryptoEngine {
    private let keys = Array<Int32>(3, repeat: 0)

    public func initKeys(password: Array<Rune>, useUtf8ForPassword: Bool) {
        keys[0] = 305419896
        keys[1] = 591751049
        keys[2] = 878082192
        var bytes = Zip4cjUtil.convertCharArrayToByteArray(password, useUtf8ForPassword)
        for (i in 0..bytes.size) {
            updateKeys((bytes[i] & 0xff))
        }
    }

    @OverflowWrapping
    public func updateKeys(charAt: Byte) {
        keys[0] = crc32(keys[0], charAt)
        keys[1] += keys[0] & 0xff
        keys[1] = keys[1] * 134775813 + 1
        keys[2] = crc32(keys[2], UInt8(keys[1] >> 24))
    }

    @OverflowWrapping
    private func crc32(oldCrc: Int32, charAt: Byte): Int32 {
        return ((oldCrc[8]) ^ CRC_TABLE[Int64(oldCrc ^ Int32(charAt)) & 0xff])
    }

    @OverflowWrapping
    public func decryptByte(): Byte {
        var temp = keys[2] | 2
        return UInt8((temp * (temp ^ 1))[8])
    }
}