package org.checkerframework.framework.test.junit;

import com.sun.source.tree.ArrayAccessTree;
import com.sun.source.tree.ExpressionTree;
import com.sun.source.tree.IdentifierTree;
import com.sun.source.tree.LiteralTree;
import com.sun.source.tree.MemberSelectTree;
import com.sun.source.tree.MethodInvocationTree;
import com.sun.tools.javac.processing.JavacProcessingEnvironment;
import com.sun.tools.javac.util.Context;
import javax.annotation.processing.ProcessingEnvironment;
import org.checkerframework.javacutil.trees.TreeParser;
import org.junit.Assert;
import org.junit.Test;

public class TreeParserTest {
  private final ProcessingEnvironment env;
  private final TreeParser parser;

  public TreeParserTest() {
    env = JavacProcessingEnvironment.instance(new Context());
    parser = new TreeParser(env);
  }

  @Test
  public void parsesIdentifiers() {
    String value = "id";
    ExpressionTree parsed = parser.parseTree(value);

    Assert.assertTrue(parsed instanceof IdentifierTree);
  }

  @Test
  public void parsesNumbers() {
    String value = "23";
    ExpressionTree parsed = parser.parseTree(value);

    Assert.assertTrue(parsed instanceof LiteralTree);
  }

  @Test
  public void parsesMethodInvocations() {
    String value = "test()";
    ExpressionTree parsed = parser.parseTree(value);

    Assert.assertTrue(parsed instanceof MethodInvocationTree);
    MethodInvocationTree invocation = (MethodInvocationTree) parsed;
    Assert.assertTrue(invocation.getMethodSelect() instanceof IdentifierTree);
    Assert.assertEquals(
        "test", ((IdentifierTree) invocation.getMethodSelect()).getName().toString());
  }

  @Test
  public void parsesMethodInvocationsWithSelect() {
    String value = "Class.test()";
    ExpressionTree parsed = parser.parseTree(value);

    Assert.assertTrue(parsed instanceof MethodInvocationTree);
    MethodInvocationTree invocation = (MethodInvocationTree) parsed;
    Assert.assertTrue(invocation.getMethodSelect() instanceof MemberSelectTree);
    MemberSelectTree select = (MemberSelectTree) invocation.getMethodSelect();
    Assert.assertEquals("test", select.getIdentifier().toString());
    Assert.assertEquals("Class", select.getExpression().toString());
  }

  @Test
  public void parsesIndex() {
    String value = "array[2]";
    ExpressionTree parsed = parser.parseTree(value);

    Assert.assertTrue(parsed instanceof ArrayAccessTree);
    ArrayAccessTree access = (ArrayAccessTree) parsed;

    Assert.assertEquals(2, ((LiteralTree) access.getIndex()).getValue());
    Assert.assertEquals("array", ((IdentifierTree) access.getExpression()).getName().toString());
  }

  @Test
  public void randomParses() {
    ExpressionTree parsed = parser.parseTree("Class.method()[4].field[3]");

    Assert.assertTrue(parsed instanceof ArrayAccessTree);
    MemberSelectTree array = (MemberSelectTree) ((ArrayAccessTree) parsed).getExpression();
    Assert.assertEquals("field", array.getIdentifier().toString());
    Assert.assertTrue(array.getExpression() instanceof ArrayAccessTree);
  }

  @Test
  public void parsesMethodArguments() {
    parser.parseTree("method()");
    parser.parseTree("method(1)");
    parser.parseTree("method(1,2)");
  }
}