<?php

if (class_exists('ParagonIE_Sodium_Core32_HSalsa20', false)) {

    return;

}

/**

 * Class ParagonIE_Sodium_Core32_HSalsa20

 */

abstract class ParagonIE_Sodium_Core32_HSalsa20 extends ParagonIE_Sodium_Core32_Salsa20

{

    /**

     * Calculate an hsalsa20 hash of a single block

     *

     * HSalsa20 doesn't have a counter and will never be used for more than

     * one block (used to derive a subkey for xsalsa20).

     *

     * @internal You should not use this directly from another application

     *

     * @param string $in

     * @param string $k

     * @param string|null $c

     * @return string

     * @throws SodiumException

     * @throws TypeError

     */

    public static function hsalsa20($in, $k, $c = null)

    {

        /**

         * @var ParagonIE_Sodium_Core32_Int32 $x0

         * @var ParagonIE_Sodium_Core32_Int32 $x1

         * @var ParagonIE_Sodium_Core32_Int32 $x2

         * @var ParagonIE_Sodium_Core32_Int32 $x3

         * @var ParagonIE_Sodium_Core32_Int32 $x4

         * @var ParagonIE_Sodium_Core32_Int32 $x5

         * @var ParagonIE_Sodium_Core32_Int32 $x6

         * @var ParagonIE_Sodium_Core32_Int32 $x7

         * @var ParagonIE_Sodium_Core32_Int32 $x8

         * @var ParagonIE_Sodium_Core32_Int32 $x9

         * @var ParagonIE_Sodium_Core32_Int32 $x10

         * @var ParagonIE_Sodium_Core32_Int32 $x11

         * @var ParagonIE_Sodium_Core32_Int32 $x12

         * @var ParagonIE_Sodium_Core32_Int32 $x13

         * @var ParagonIE_Sodium_Core32_Int32 $x14

         * @var ParagonIE_Sodium_Core32_Int32 $x15

         * @var ParagonIE_Sodium_Core32_Int32 $j0

         * @var ParagonIE_Sodium_Core32_Int32 $j1

         * @var ParagonIE_Sodium_Core32_Int32 $j2

         * @var ParagonIE_Sodium_Core32_Int32 $j3

         * @var ParagonIE_Sodium_Core32_Int32 $j4

         * @var ParagonIE_Sodium_Core32_Int32 $j5

         * @var ParagonIE_Sodium_Core32_Int32 $j6

         * @var ParagonIE_Sodium_Core32_Int32 $j7

         * @var ParagonIE_Sodium_Core32_Int32 $j8

         * @var ParagonIE_Sodium_Core32_Int32 $j9

         * @var ParagonIE_Sodium_Core32_Int32 $j10

         * @var ParagonIE_Sodium_Core32_Int32 $j11

         * @var ParagonIE_Sodium_Core32_Int32 $j12

         * @var ParagonIE_Sodium_Core32_Int32 $j13

         * @var ParagonIE_Sodium_Core32_Int32 $j14

         * @var ParagonIE_Sodium_Core32_Int32 $j15

         */

        if (self::strlen($k) < 32) {

            throw new RangeException('Key must be 32 bytes long');

        }

        if ($c === null) {

            $x0  = new ParagonIE_Sodium_Core32_Int32(array(0x6170, 0x7865));

            $x5  = new ParagonIE_Sodium_Core32_Int32(array(0x3320, 0x646e));

            $x10 = new ParagonIE_Sodium_Core32_Int32(array(0x7962, 0x2d32));

            $x15 = new ParagonIE_Sodium_Core32_Int32(array(0x6b20, 0x6574));

        } else {

            $x0  = ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($c, 0, 4));

            $x5  = ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($c, 4, 4));

            $x10 = ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($c, 8, 4));

            $x15 = ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($c, 12, 4));

        }

        $x1  = ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($k, 0, 4));

        $x2  = ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($k, 4, 4));

        $x3  = ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($k, 8, 4));

        $x4  = ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($k, 12, 4));

        $x6  = ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($in, 0, 4));

        $x7  = ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($in, 4, 4));

        $x8  = ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($in, 8, 4));

        $x9  = ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($in, 12, 4));

        $x11 = ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($k, 16, 4));

        $x12 = ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($k, 20, 4));

        $x13 = ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($k, 24, 4));

        $x14 = ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($k, 28, 4));

        for ($i = self::ROUNDS; $i > 0; $i -= 2) {

            $x4  = $x4->xorInt32($x0->addInt32($x12)->rotateLeft(7));

            $x8  = $x8->xorInt32($x4->addInt32($x0)->rotateLeft(9));

            $x12 = $x12->xorInt32($x8->addInt32($x4)->rotateLeft(13));

            $x0  = $x0->xorInt32($x12->addInt32($x8)->rotateLeft(18));

            $x9  = $x9->xorInt32($x5->addInt32($x1)->rotateLeft(7));

            $x13 = $x13->xorInt32($x9->addInt32($x5)->rotateLeft(9));

            $x1  = $x1->xorInt32($x13->addInt32($x9)->rotateLeft(13));

            $x5  = $x5->xorInt32($x1->addInt32($x13)->rotateLeft(18));

            $x14 = $x14->xorInt32($x10->addInt32($x6)->rotateLeft(7));

            $x2  = $x2->xorInt32($x14->addInt32($x10)->rotateLeft(9));

            $x6  = $x6->xorInt32($x2->addInt32($x14)->rotateLeft(13));

            $x10 = $x10->xorInt32($x6->addInt32($x2)->rotateLeft(18));

            $x3  = $x3->xorInt32($x15->addInt32($x11)->rotateLeft(7));

            $x7  = $x7->xorInt32($x3->addInt32($x15)->rotateLeft(9));

            $x11 = $x11->xorInt32($x7->addInt32($x3)->rotateLeft(13));

            $x15 = $x15->xorInt32($x11->addInt32($x7)->rotateLeft(18));

            $x1  = $x1->xorInt32($x0->addInt32($x3)->rotateLeft(7));

            $x2  = $x2->xorInt32($x1->addInt32($x0)->rotateLeft(9));

            $x3  = $x3->xorInt32($x2->addInt32($x1)->rotateLeft(13));

            $x0  = $x0->xorInt32($x3->addInt32($x2)->rotateLeft(18));

            $x6  = $x6->xorInt32($x5->addInt32($x4)->rotateLeft(7));

            $x7  = $x7->xorInt32($x6->addInt32($x5)->rotateLeft(9));

            $x4  = $x4->xorInt32($x7->addInt32($x6)->rotateLeft(13));

            $x5  = $x5->xorInt32($x4->addInt32($x7)->rotateLeft(18));

            $x11 = $x11->xorInt32($x10->addInt32($x9)->rotateLeft(7));

            $x8  = $x8->xorInt32($x11->addInt32($x10)->rotateLeft(9));

            $x9  = $x9->xorInt32($x8->addInt32($x11)->rotateLeft(13));

            $x10 = $x10->xorInt32($x9->addInt32($x8)->rotateLeft(18));

            $x12 = $x12->xorInt32($x15->addInt32($x14)->rotateLeft(7));

            $x13 = $x13->xorInt32($x12->addInt32($x15)->rotateLeft(9));

            $x14 = $x14->xorInt32($x13->addInt32($x12)->rotateLeft(13));

            $x15 = $x15->xorInt32($x14->addInt32($x13)->rotateLeft(18));

        }

        return $x0->toReverseString() .

            $x5->toReverseString() .

            $x10->toReverseString() .

            $x15->toReverseString() .

            $x6->toReverseString() .

            $x7->toReverseString() .

            $x8->toReverseString() .

            $x9->toReverseString();

    }

}