/*
 * lemonad - Some functional sweetness for Java
 * Copyright (C) 2019  Pacien TRAN-GIRARD
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

package org.pacien.lemonad.validation;

import org.junit.jupiter.api.Assertions;
import org.junit.jupiter.api.Test;
import org.pacien.lemonad.attempt.Attempt;

import java.util.List;

import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertFalse;
import static org.junit.jupiter.api.Assertions.assertTrue;
import static org.junit.jupiter.api.Assertions.fail;

/**
 * @author pacien
 */
class ValidationTest {
  @Test void testValidResult() {
    var subject = "subject";
    var validation = Validation.of(subject);
    assertTrue(validation.getErrors().isEmpty());
    assertTrue(validation.isValid());
    assertFalse(validation.isInvalid());
    validation.ifValid(innerSubject -> assertEquals(subject, innerSubject));
    validation.ifInvalid((__, ___) -> fail());
    assertEquals(Attempt.success(subject), validation.toAttempt());
  }

  @Test void testInvalidResult() {
    var subject = "subject";
    var errors = List.of(0, 1);
    var validation = Validation.of(subject, 0, 1);
    assertEquals(errors, validation.getErrors());
    assertFalse(validation.isValid());
    assertTrue(validation.isInvalid());
    validation.ifValid(Assertions::fail);
    validation.ifInvalid((innerSubject, innerErrors) -> {
      assertEquals(subject, innerSubject);
      assertEquals(errors, innerErrors);
    });
    assertEquals(Attempt.failure(errors), validation.toAttempt());
  }

  @Test void testFlatMap() {
    Validation
      .of("subject")
      .ifInvalid((__, ___) -> fail())
      .flatMap(res -> Validation.of(res.getSubject(), 0))
      .ifValid(innerSubject -> fail());
  }

  @Test void testMerge() {
    var validation = Validation
      .of(12345, 0)
      .merge(s -> Validation.of(s, 1))
      .merge((Integer s) -> Integer.toString(s), (String s) -> Validation.of(s, 2))
      .merge(Validation.of(0L, List.of(3)))
      .merge(List.of(4));

    assertEquals(Validation.of(12345, 0, 1, 2, 3, 4), validation);
  }

  @Test void testValidate() {
    var validation = Validation
      .of("subject")
      .validate(String::isEmpty, 0)
      .validate(String::length, len -> len > 0, 1)
      .validate(subject -> List.of(2, 3))
      .validate(subject -> subject.charAt(0), firstChar -> firstChar == 's' ? List.of() : List.of(4));

    assertEquals(Validation.of("subject", 0, 2, 3), validation);
  }
}