/*
 * RiskScape™ Copyright New Zealand Institute for Earth Science Limited
 * (Earth Sciences New Zealand) is distributed for research purposes only
 * under the terms of AGPLv3.
 *
 * RiskScape™ Copyright 2026 New Zealand Institute for Earth Science
 * Limited (Earth Sciences New Zealand). All rights reserved. Source code
 * available under the AGPLv3.
 * 
 * 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 for RESEARCH PURPOSES ONLY, in the hope that it will
 * be useful for research and education initiatives.
 * 
 * If you are not a researcher, or you are a researcher who wishes to use this
 * program on terms other than AGPLv3 (including those who wish to restrict the
 * distribution of any source code created using this program), please contact:
 * https://riskscape.org.nz
 * 
 * This program is distributed 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
 * <http://www.gnu.org/licenses/>.
 * 
 * By way of summary only, under the AGPLv3:
 *     • Permissions of this strongest copyleft license are conditioned
 *       on making available complete source code of licensed works and
 *       modifications, which include larger works using a licensed work,
 *       under the same license.
 *     • Copyright and license notices must be preserved.
 *     • Contributors provide an express grant of patent rights.
 *     • When a modified version is used to provide a service over a
 *       network, the complete source code of the modified version must be made
 *       available.
 */
package nz.org.riskscape.rl.ast;

import static org.junit.Assert.*;

import org.junit.Test;

import nz.org.riskscape.rl.ExpressionParser;

public class ExpressionLiteralTest {

  private final ExpressionParser parser = new ExpressionParser();

  private Expression parse(String expr) {
    return parser.parse(expr);
  }

  @Test
  public void constantIsLiteral() {
    assertTrue(parse("42").isLiteral());
    assertTrue(parse("'hello'").isLiteral());
    assertTrue(parse("3.14").isLiteral());
    assertTrue(parse("true").isLiteral());
    assertTrue(parse("false").isLiteral());
  }

  @Test
  public void emptyListIsLiteral() {
    assertTrue(parse("[]").isLiteral());
  }

  @Test
  public void listOfConstantsIsLiteral() {
    assertTrue(parse("[1, 2, 3]").isLiteral());
  }

  @Test
  public void listWithNonLiteralIsNotLiteral() {
    assertFalse(parse("[1, foo, 3]").isLiteral());
  }

  @Test
  public void nestedListOfLiteralsIsLiteral() {
    assertTrue(parse("[[1, 2], 3]").isLiteral());
  }

  @Test
  public void emptyStructIsLiteral() {
    assertTrue(parse("{}").isLiteral());
  }

  @Test
  public void structOfConstantsIsLiteral() {
    assertTrue(parse("{a: 1, b: 'text'}").isLiteral());
  }

  @Test
  public void structWithNonLiteralIsNotLiteral() {
    assertFalse(parse("{a: 1, b: foo}").isLiteral());
  }

  @Test
  public void nestedStructOfLiteralsIsLiteral() {
    assertTrue(parse("{inner: {x: 10}, y: 20}").isLiteral());
  }

  @Test
  public void structWithLiteralListIsLiteral() {
    assertTrue(parse("{items: [1, 2]}").isLiteral());
  }

  @Test
  public void propertyAccessIsNotLiteral() {
    assertFalse(parse("foo").isLiteral());
    assertFalse(parse("foo.bar.baz").isLiteral());
  }

  @Test
  public void propertyAccessOnAStructIsLiteralIfThePropertyWasLiteral() {
    assertTrue(parse("{foo: 'bar'}.foo").isLiteral());
  }

  @Test
  public void propertyAccessOnAStructIsNotLiteralIfThePropertyWasNotLiteral() {
    assertFalse(parse("{foo: bar}.foo").isLiteral());
  }

  @Test
  public void propertyAccessOnAStructIsNotLiteralIfThePropertyWasLiteralButOthersAreNot() {
    // this is an awkward case - because the struct is not literal, the ast isn't smart enough to see that accessing
    // foo isn't itself literal.  Realization could determine this, but not the ast.
    assertFalse(parse("{foo: 'bar', baz: qux}.foo").isLiteral());
  }

  @Test
  public void functionCallIsNotLiteral() {
    assertFalse(parse("myFunc(1)").isLiteral());
  }

  @Test
  public void lambdaIsNotLiteral() {
    assertFalse(parse("x -> 1").isLiteral());
  }

  @Test
  public void binaryOperationWithLiteralsIsLiteral() {
    assertTrue(parse("1 + 2").isLiteral());
    assertTrue(parse("3 * 4").isLiteral());
    assertTrue(parse("true and false").isLiteral());
  }

  @Test
  public void binaryOperationWithNonLiteralIsNotLiteral() {
    assertFalse(parse("1 + x").isLiteral());
    assertFalse(parse("x * 4").isLiteral());
  }

  @Test
  public void bracketedLiteralIsLiteral() {
    assertTrue(parse("(42)").isLiteral());
    assertTrue(parse("(1 + 2)").isLiteral());
  }

  @Test
  public void bracketedNonLiteralIsNotLiteral() {
    assertFalse(parse("(foo)").isLiteral());
  }

  @Test
  public void complexLiteralStructure() {
        assertTrue(parse("{a: [1, 2, {x: 3}], b: 4 + 5}").isLiteral());
  }

  @Test
  public void complexNonLiteralStructure() {
    assertFalse(parse("{a: [1, foo(), 3], b: 4}").isLiteral());
  }
}
