/*
 * 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.juneau.bct.assertions;

import static java.util.Arrays.*;
import static java.util.Collections.*;
import static java.util.stream.Collectors.*;

import java.io.*;
import java.util.*;
import java.util.function.*;

import org.apache.juneau.commons.function.*;
import org.apache.juneau.commons.utils.*;

/**
 * Used for fluent assertion calls against maps.
 *
 * <h5 class='section'>Test Methods:</h5>
 * <p>
 * <ul class='javatree'>
 *    <li class='jc'>{@link FluentMapAssertion}
 *    <ul class='javatreec'>
 *       <li class='jm'>{@link FluentMapAssertion#isEmpty() isEmpty()}
 *       <li class='jm'>{@link FluentMapAssertion#isNotEmpty() isNotEmpty()}
 *       <li class='jm'>{@link FluentMapAssertion#isContainsKey(String) isContainsKey(String)}
 *       <li class='jm'>{@link FluentMapAssertion#isNotContainsKey(String) isNotContainsKey(String)}
 *       <li class='jm'>{@link FluentMapAssertion#isSize(int) isSize(int)}
 *    </ul>
 *    <li class='jc'>{@link FluentObjectAssertion}
 *    <ul class='javatreec'>
 *       <li class='jm'>{@link FluentObjectAssertion#isExists() isExists()}
 *       <li class='jm'>{@link FluentObjectAssertion#is(Object) is(Object)}
 *       <li class='jm'>{@link FluentObjectAssertion#is(Predicate) is(Predicate)}
 *       <li class='jm'>{@link FluentObjectAssertion#isNot(Object) isNot(Object)}
 *       <li class='jm'>{@link FluentObjectAssertion#isAny(Object...) isAny(Object...)}
 *       <li class='jm'>{@link FluentObjectAssertion#isNotAny(Object...) isNotAny(Object...)}
 *       <li class='jm'>{@link FluentObjectAssertion#isNull() isNull()}
 *       <li class='jm'>{@link FluentObjectAssertion#isNotNull() isNotNull()}
 *       <li class='jm'>{@link FluentObjectAssertion#isString(String) isString(String)}
 *       <li class='jm'>{@link FluentObjectAssertion#isSame(Object) isSame(Object)}
 *       <li class='jm'>{@link FluentObjectAssertion#isType(Class) isType(Class)}
 *       <li class='jm'>{@link FluentObjectAssertion#isExactType(Class) isExactType(Class)}
 *    </ul>
 * </ul>
 *
 * <h5 class='section'>Transform Methods:</h5>
 * <p>
 * <ul class='javatree'>
 *    <li class='jc'>{@link FluentMapAssertion}
 *    <ul class='javatreec'>
 *       <li class='jm'>{@link FluentMapAssertion#asValue(Object) asValue(Object)}
 *       <li class='jm'>{@link FluentMapAssertion#asValues(Object...) asValues(Object...)}
 *       <li class='jm'>{@link FluentMapAssertion#asValueMap(Object...) asValueMap(Object...)}
 *       <li class='jm'>{@link FluentMapAssertion#asSize() asSize()}
 *    </ul>
 *    <li class='jc'>{@link FluentObjectAssertion}
 *    <ul class='javatreec'>
 *       <li class='jm'>{@link FluentObjectAssertion#asString() asString()}
 *       <li class='jm'>{@link FluentObjectAssertion#asString(ThrowingFunction) asString(ThrowingFunction)}
 *       <li class='jm'>{@link FluentObjectAssertion#asTransformed(UnaryOperator) asTransformed(UnaryOperator)}
 *       <li class='jm'>{@link FluentObjectAssertion#asAny() asAny()}
 * </ul>
 * </ul>
 *
 * <h5 class='section'>Configuration Methods:</h5>
 * <p>
 * <ul class='javatree'>
 *    <li class='jc'>{@link Assertion}
 *    <ul class='javatreec'>
 *       <li class='jm'>{@link Assertion#setMsg(String, Object...) setMsg(String, Object...)}
 *       <li class='jm'>{@link Assertion#setOut(PrintStream) setOut(PrintStream)}
 *       <li class='jm'>{@link Assertion#setSilent() setSilent()}
 *       <li class='jm'>{@link Assertion#setStdOut() setStdOut()}
 *       <li class='jm'>{@link Assertion#setThrowable(Class) setThrowable(Class)}
 *    </ul>
 * </ul>
 *
 * <h5 class='section'>See Also:</h5><ul>
 *    <li class='link'><a class="doclink" href="https://juneau.apache.org/docs/topics/JuneauEcosystemOverview">Juneau Ecosystem</a>
 * </ul>
 *
 * @param <K> The key type.
 * @param <V> The value type.
 * @param <R> The return type.
 */
@SuppressWarnings({
   "java:S115", // Constants use UPPER_snakeCase convention (e.g., MSG_mapWasNotEmpty)
   "unchecked" // Generic varargs parameters (K...keys) in the key-based assertion methods create generic arrays at call sites
})
public class FluentMapAssertion<K,V,R> extends FluentObjectAssertion<Map<K,V>,R> {

   private static final Messages MESSAGES = Messages.of(FluentMapAssertion.class, "Messages");
   private static final String MSG_mapWasNotEmpty = MESSAGES.getString("mapWasNotEmpty");
   private static final String MSG_mapDidNotContainExpectedKey = MESSAGES.getString("mapDidNotContainExpectedKey");
   private static final String MSG_mapContainedUnexpectedKey = MESSAGES.getString("mapContainedUnexpectedKey");
   private static final String MSG_mapWasEmpty = MESSAGES.getString("mapWasEmpty");
   private static final String MSG_mapDidNotHaveTheExpectedSize = MESSAGES.getString("mapDidNotHaveTheExpectedSize");

   /**
    * Chained constructor.
    *
    * <p>
    * Used when transforming one assertion into another so that the assertion config can be used by the new assertion.
    *
    * @param creator
    *    The assertion that created this assertion.
    *    <br>Should be <jk>null</jk> if this is the top-level assertion.
    * @param value
    *    The object being tested.
    *    <br>Can be <jk>null</jk> (assertions such as {@code isNull()} then operate on the absence of a value).
    * @param returns
    *    The object to return after a test method is called.
    *    <br>If <jk>null</jk>, the test method returns this object allowing multiple test method calls to be
    * used on the same assertion.
    */
   public FluentMapAssertion(Assertion creator, Map<K,V> value, R returns) {
      super(creator, value, returns);
   }

   /**
    * Constructor.
    *
    * @param value
    *    The object being tested.
    *    <br>Can be <jk>null</jk> (assertions such as {@code isNull()} then operate on the absence of a value).
    * @param returns
    *    The object to return after a test method is called.
    *    <br>If <jk>null</jk>, the test method returns this object allowing multiple test method calls to be
    * used on the same assertion.
    */
   public FluentMapAssertion(Map<K,V> value, R returns) {
      this(null, value, returns);
   }

   /**
    * Returns an integer assertion on the size of this map.
    *
    * <p>
    * If the map is <jk>null</jk>, the returned assertion is a null assertion
    * (meaning {@link FluentIntegerAssertion#isExists()} returns <jk>false</jk>).
    *
    * @return A new assertion.
    */
   public FluentIntegerAssertion<R> asSize() {
      return new FluentIntegerAssertion<>(this, valueIsNull() ? null : value().size(), returns());
   }

   @Override /* Overridden from FluentObjectAssertion */
   public FluentMapAssertion<K,V,R> asTransformed(UnaryOperator<Map<K,V>> function) {
      return new FluentMapAssertion<>(this, function.apply(orElse(null)), returns());
   }

   /**
    * Returns an object assertion on the value specified at the specified key.
    *
    * <p>
    * If the map is <jk>null</jk> or the map doesn't contain the specified key, the returned assertion is a null assertion
    * (meaning {@link FluentAnyAssertion#isExists()} returns <jk>false</jk>).
    *
    * @param key The key of the item to retrieve from the map.
    * @return A new assertion.
    */
   public FluentAnyAssertion<V,R> asValue(K key) {
      return new FluentAnyAssertion<>(this, get(key), returns());
   }

   /**
    * Extracts a subset of this map.
    *
    * @param keys The entries to extract.
    * @return This object.
    */
   public FluentMapAssertion<K,V,R> asValueMap(K...keys) {
      if (valueIsNull())
         return new FluentMapAssertion<>(this, null, returns());
      var m1 = value();
      Map<K,V> m2 = CollectionUtils.map();
      for (var k : keys)
         m2.put(k, m1.get(k));
      return new FluentMapAssertion<>(this, m2, returns());
   }

   /**
    * Returns a {@link FluentListAssertion} of the values of the specified keys.
    *
    * If the map is <jk>null</jk>, the returned assertion is a null assertion
    * (meaning {@link FluentObjectAssertion#isExists()} returns <jk>false</jk>).
    *
    * @param keys The keys of the values to retrieve from the map.
    * @return A new assertion.
    */
   public FluentListAssertion<Object,R> asValues(K...keys) {
      return new FluentListAssertion<>(this, valueIsNull() ? null : stream(keys).map(this::get).collect(toList()), returns());
   }

   /**
    * Asserts that the map contains the expected key.
    *
    * @param name The key name to check for.
    * @return The fluent return object.
    * @throws AssertionError If assertion failed or value was <jk>null</jk>.
    */
   public R isContainsKey(String name) throws AssertionError {
      if (value().containsKey(name))
         return returns();
      throw error(MSG_mapDidNotContainExpectedKey, name, value());
   }

   /**
    * Asserts that the map exists and is empty.
    *
    * @return The fluent return object.
    * @throws AssertionError If assertion failed or value was <jk>null</jk>.
    */
   public R isEmpty() throws AssertionError {
      if (! value().isEmpty())
         throw error(MSG_mapWasNotEmpty);
      return returns();
   }

   /**
    * Asserts that the map contains the expected key.
    *
    * @param name The key name to check for.
    * @return The fluent return object.
    * @throws AssertionError If assertion failed or value was <jk>null</jk>.
    */
   public R isNotContainsKey(String name) throws AssertionError {
      if (! value().containsKey(name))
         return returns();
      throw error(MSG_mapContainedUnexpectedKey, name, value());
   }

   /**
    * Asserts that the map exists and is not empty.
    *
    * @return The fluent return object.
    * @throws AssertionError If assertion failed or value was <jk>null</jk>.
    */
   public R isNotEmpty() throws AssertionError {
      if (value().isEmpty())
         throw error(MSG_mapWasEmpty);
      return returns();
   }

   /**
    * Asserts that the map exists and is the specified size.
    *
    * @param size The expected size.
    * @return The fluent return object.
    * @throws AssertionError If assertion failed or value was <jk>null</jk>.
    */
   public R isSize(int size) throws AssertionError {
      if (size2() != size)
         throw error(MSG_mapDidNotHaveTheExpectedSize, size, size2());
      return returns();
   }

   @Override /* Overridden from Assertion */
   public FluentMapAssertion<K,V,R> setMsg(String msg, Object...args) {
      super.setMsg(msg, args);
      return this;
   }

   @Override /* Overridden from Assertion */
   public FluentMapAssertion<K,V,R> setOut(PrintStream value) {
      super.setOut(value);
      return this;
   }

   @Override /* Overridden from Assertion */
   public FluentMapAssertion<K,V,R> setSilent() {
      super.setSilent();
      return this;
   }

   @Override /* Overridden from Assertion */
   public FluentMapAssertion<K,V,R> setStdOut() {
      super.setStdOut();
      return this;
   }

   @Override /* Overridden from Assertion */
   public FluentMapAssertion<K,V,R> setThrowable(Class<? extends RuntimeException> value) {
      super.setThrowable(value);
      return this;
   }

   private V get(K key) {
      return orElse(emptyMap()).get(key);
   }

   private int size2() {
      return value().size();
   }
}