/*
    * 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.numbers.field;
  
  import org.junit.jupiter.api.Assertions;
  import org.junit.jupiter.params.ParameterizedTest;
  import org.junit.jupiter.params.provider.MethodSource;
  import java.util.Arrays;
  import java.util.function.BiPredicate;
  import java.util.stream.Stream;
  
  import org.apache.commons.numbers.core.Addition;
  import org.apache.commons.numbers.core.Multiplication;
  
  /**
   * Tests for fields.
   */
  class FieldParametricTest {
  
      private static Stream<FieldTestData<?>> getList() {
          return FieldsList.stream();
      }
  
      @ParameterizedTest
      @MethodSource("getList")
      <T> void testAdditionAssociativity(FieldTestData<T> data) {
          Field<T> field = data.getField();
          T a = data.getA();
          T b = data.getB();
          T c = data.getC();
          final T r1 = field.add(field.add(a, b), c);
          final T r2 = field.add(a, field.add(b, c));
          assertEquals(r1, r2, data::equals);
      }
  
      @ParameterizedTest
      @MethodSource("getList")
      <T> void testAdditionCommutativity(FieldTestData<T> data) {
          Field<T> field = data.getField();
          T a = data.getA();
          T b = data.getB();
          final T r1 = field.add(a, b);
          final T r2 = field.add(b, a);
          assertEquals(r1, r2, data::equals);
      }
  
      @ParameterizedTest
      @MethodSource("getList")
      <T> void testAdditiveIdentity(FieldTestData<T> data) {
          Field<T> field = data.getField();
          T a = data.getA();
          final T r1 = field.add(a, field.zero());
          final T r2 = a;
          assertEquals(r1, r2, data::equals);
      }
  
      @ParameterizedTest
      @MethodSource("getList")
      <T> void testAdditiveInverse(FieldTestData<T> data) {
          Field<T> field = data.getField();
          T a = data.getA();
          final T r1 = field.add(a, field.negate(a));
          final T r2 = field.zero();
          assertEquals(r1, r2, data::equals);
      }
  
      @ParameterizedTest
      @MethodSource("getList")
      <T> void testMultiplicationAssociativity(FieldTestData<T> data) {
          Field<T> field = data.getField();
          T a = data.getA();
          T b = data.getB();
          T c = data.getC();
          final T r1 = field.multiply(field.multiply(a, b), c);
          final T r2 = field.multiply(a, field.multiply(b, c));
          assertEquals(r1, r2, data::equals);
      }
  
      @ParameterizedTest
      @MethodSource("getList")
      <T> void testMultiplicationCommutativity(FieldTestData<T> data) {
          Field<T> field = data.getField();
          T a = data.getA();
          T b = data.getB();
          final T r1 = field.multiply(a, b);
         final T r2 = field.multiply(b, a);
         assertEquals(r1, r2, data::equals);
     }
 
     @ParameterizedTest
     @MethodSource("getList")
     <T> void testMultiplicativeIdentity(FieldTestData<T> data) {
         Field<T> field = data.getField();
         T a = data.getA();
         final T r1 = field.multiply(a, field.one());
         final T r2 = a;
         assertEquals(r1, r2, data::equals);
     }
 
     @ParameterizedTest
     @MethodSource("getList")
     <T> void testMultiplicativeInverse(FieldTestData<T> data) {
         Field<T> field = data.getField();
         T a = data.getA();
         final T r1 = field.multiply(a, field.reciprocal(a));
         final T r2 = field.one();
         assertEquals(r1, r2, data::equals);
     }
 
     @ParameterizedTest
     @MethodSource("getList")
     <T> void testDistributivity(FieldTestData<T> data) {
         Field<T> field = data.getField();
         T a = data.getA();
         T b = data.getB();
         T c = data.getC();
         final T r1 = field.multiply(a, field.add(b, c));
         final T r2 = field.add(field.multiply(a, b), field.multiply(a, c));
         assertEquals(r1, r2, data::equals);
     }
 
     @ParameterizedTest
     @MethodSource("getList")
     <T extends Addition<T>> void testAdd(FieldTestData<T> data) {
         Field<T> field = data.getField();
         T a = data.getA();
         T b = data.getB();
 
         final T r1 = field.add(a, b);
         final T r2 = a.add(b);
         assertEquals(r1, r2, data::equals);
     }
 
     @ParameterizedTest
     @MethodSource("getList")
     <T extends Addition<T>> void testSubtract(FieldTestData<T> data) {
         Field<T> field = data.getField();
         T a = data.getA();
         T b = data.getB();
 
         final T r1 = field.subtract(a, b);
         final T r2 = a.add(b.negate());
         assertEquals(r1, r2, data::equals);
     }
 
     @ParameterizedTest
     @MethodSource("getList")
     <T extends Addition<T>> void testMultiplyInt(FieldTestData<T> data) {
         Field<T> field = data.getField();
         T a = data.getA();
         final int n = 5;
 
         final T r1 = field.multiply(n, a);
 
         T r2 = field.zero();
         for (int i = 0; i < n; i++) {
             r2 = r2.add(a);
         }
 
         assertEquals(r1, r2, data::equals);
     }
 
     @ParameterizedTest
     @MethodSource("getList")
     <T extends Addition<T>> void testZero(FieldTestData<T> data) {
         Field<T> field = data.getField();
         T a = data.getA();
 
         final T r1 = field.zero();
         final T r2 = a.zero();
         assertEquals(r1, r2, data::equals);
 
         // Test the definition:
         // zero().add(a).equals(a)
         // Here we ignore the equality predicate so there is no tolerance
         Arrays.asList(a, data.getB(), data.getC())
               .forEach(t -> Assertions.assertEquals(t, r2.add(t), () -> "zero add " + t));
     }
 
     @ParameterizedTest
     @MethodSource("getList")
     <T extends Multiplication<T>> void testMultiply(FieldTestData<T> data) {
         Field<T> field = data.getField();
         T a = data.getA();
         T b = data.getB();
 
         final T r1 = field.multiply(a, b);
         final T r2 = a.multiply(b);
         assertEquals(r1, r2, data::equals);
     }
 
     @ParameterizedTest
     @MethodSource("getList")
     <T extends Multiplication<T>> void testDivide(FieldTestData<T> data) {
         Field<T> field = data.getField();
         T a = data.getA();
         T b = data.getB();
 
         final T r1 = field.divide(a, b);
         final T r2 = a.multiply(b.reciprocal());
         assertEquals(r1, r2, data::equals);
     }
 
     @ParameterizedTest
     @MethodSource("getList")
     <T extends Multiplication<T>> void testOne(FieldTestData<T> data) {
         Field<T> field = data.getField();
         T a = data.getA();
 
         final T r1 = field.one();
         final T r2 = a.one();
         assertEquals(r1, r2, data::equals);
 
         // Test the definition:
         // one().multiply(a).equals(a)
         // Here we ignore the equality predicate so there is no tolerance
         Arrays.asList(a, data.getB(), data.getC())
               .forEach(t -> Assertions.assertEquals(t, r2.multiply(t), () -> "one multiply " + t));
     }
 
     /**
      * @param a Instance.
      * @param b Instance.
      */
     private static <T> void assertEquals(T a,
                                          T b,
                                          BiPredicate<T, T> equals) {
         Assertions.assertTrue(equals.test(a, b), () -> a + " != " + b);
     }
 }