/*
    * Licensed to the Apache Software Foundation (ASF) under one or more
    * contributor license agreements.  See the NOTICE file distributed with
    * this work for additional information regarding copyright ownership.
    * The ASF licenses this file to You under the Apache License, Version 2.0
    * (the "License"); you may not use this file except in compliance with
    * the License.  You may obtain a copy of the License at
    *
    *      http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.apache.commons.rng.core.source32;
  
  import org.apache.commons.rng.core.RandomAssert;
  import org.junit.jupiter.api.Test;
  
  class XoShiRo128PlusPlusTest {
      /** The size of the array seed. */
      private static final int SEED_SIZE = 4;
  
      /*
       * Data from running the executable compiled from the author's C code:
       *   http://xoshiro.di.unimi.it/xoshiro128plusplus.c
       */
  
      private static final int[] SEED = {
          0x012de1ba, 0xa5a818b8, 0xb124ea2b, 0x18e03749,
      };
  
      private static final int[] EXPECTED_SEQUENCE = {
          0x083a6347, 0xaf13e949, 0xc170e7f6, 0x1fff4fb2,
          0x683f45ee, 0x0447edcf, 0x42e85ced, 0xaf636b74,
          0xb0087a5e, 0x75bf2669, 0xd1bce8bd, 0x421fc05e,
          0x1c6c405f, 0x14ddbffd, 0xaeacb705, 0x977ae584,
          0x2ac01aac, 0xc474ec71, 0xe0888022, 0xf94bc227,
          0x32775b57, 0x44142b05, 0x525f6d9b, 0xa2721e61,
          0x1bfe5c72, 0x17be23c2, 0x3231cc54, 0x8776866e,
          0x9ede2587, 0x0f7f144e, 0xb6f2ff9d, 0x1556365b,
          0x9e68aef3, 0x254010c3, 0x0b885bdd, 0x7c3f26bb,
          0xc8266de6, 0xcd2e6587, 0x0cbec249, 0xa69b37ba,
      };
  
      private static final int[] EXPECTED_SEQUENCE_AFTER_JUMP  = {
          0x4485d85f, 0x43f4d8a7, 0xe21ea064, 0x3eddd57d,
          0x44f6149a, 0xde7e1c16, 0xa7410410, 0x6360a4a9,
          0x34dab153, 0xfdf089b0, 0xa9b78551, 0xa2136cee,
          0x0ad2126f, 0x67a62b78, 0xa3e8c1fa, 0x19eed39b,
          0x83357624, 0xde015e70, 0xdc670b3b, 0x833dc245,
          0x4d644c84, 0x30e7ea9f, 0x9dd22362, 0x70978ced,
          0xf3d07dbb, 0xfdad08e5, 0x9118ebe0, 0x5dc55edf,
          0xcf9abe08, 0x7a822c3b, 0xa1115ecf, 0x9f8cc327,
          0x452c8954, 0xf920ef83, 0xcff75ece, 0x9622a70d,
          0x6202e501, 0x10ae0703, 0x8b7ee1be, 0xc72c1cf6,
      };
  
      private static final int[] EXPECTED_SEQUENCE_AFTER_LONG_JUMP  = {
          0x27906b5a, 0xe2ce9fb2, 0xd97f8c4f, 0x7609af7d,
          0x5b91ddd8, 0x4134b769, 0x47f505f2, 0xacc18832,
          0xeea7faf6, 0x50178ca9, 0xc15f4b36, 0xcbd206e6,
          0x4f2273cb, 0xebaabeef, 0x51e6d76f, 0xaf1fdde8,
          0x3cb5ced1, 0x04b42264, 0x2396256f, 0x9c0618ff,
          0x95ecbb0c, 0xc88c952c, 0x820664ab, 0x5d2e6153,
          0xb2003213, 0x71531ff6, 0x99d4bd53, 0xbd15fcc1,
          0x90ad002b, 0x3d37b45d, 0x500b49db, 0x6f81b35f,
          0x533f3bab, 0xe22a25fe, 0x114ca833, 0x4ab45586,
          0x077ca93d, 0xd5cf0025, 0xbe019f55, 0x8ecbe4a8,
      };
  
      @Test
      void testReferenceCode() {
          RandomAssert.assertEquals(EXPECTED_SEQUENCE, new XoShiRo128PlusPlus(SEED));
      }
  
      @Test
      void testConstructorWithZeroSeedIsNonFunctional() {
          RandomAssert.assertNextIntZeroOutput(new XoShiRo128PlusPlus(new int[SEED_SIZE]), 2 * SEED_SIZE);
      }
  
      @Test
      void testConstructorWithSingleBitSeedIsFunctional() {
          RandomAssert.assertIntArrayConstructorWithSingleBitSeedIsFunctional(XoShiRo128PlusPlus.class, SEED_SIZE);
      }
  
      @Test
      void testConstructorWithoutFullLengthSeed() {
          // Hit the case when the input seed is self-seeded when not full length
          RandomAssert.assertNextLongNonZeroOutput(new XoShiRo128PlusPlus(new int[] {SEED[0]}),
                  SEED_SIZE, SEED_SIZE);
      }
  
      @Test
      void testElementConstructor() {
          final XoShiRo128PlusPlus rng1 = new XoShiRo128PlusPlus(SEED);
          final XoShiRo128PlusPlus rng2 = new XoShiRo128PlusPlus(SEED[0], SEED[1], SEED[2], SEED[3]);
         RandomAssert.assertNextIntEquals(SEED.length * 2, rng1, rng2);
     }
 
     @Test
     void testJump() {
         RandomAssert.assertJumpEquals(EXPECTED_SEQUENCE, EXPECTED_SEQUENCE_AFTER_JUMP, new XoShiRo128PlusPlus(SEED));
     }
 
     @Test
     void testLongJump() {
         RandomAssert.assertLongJumpEquals(EXPECTED_SEQUENCE, EXPECTED_SEQUENCE_AFTER_LONG_JUMP, new XoShiRo128PlusPlus(SEED));
     }
 }