package net.bytebuddy.implementation.bytecode.member;

import net.bytebuddy.description.type.TypeDefinition;
import net.bytebuddy.implementation.Implementation;
import net.bytebuddy.implementation.bytecode.StackManipulation;
import org.junit.After;
import org.junit.Before;
import org.junit.Rule;
import org.junit.Test;
import org.junit.rules.MethodRule;
import org.junit.runner.RunWith;
import org.junit.runners.Parameterized;
import org.mockito.Mock;
import org.mockito.junit.MockitoJUnit;
import org.objectweb.asm.MethodVisitor;
import org.objectweb.asm.Opcodes;

import java.util.Arrays;
import java.util.Collection;

import static org.hamcrest.CoreMatchers.is;
import static org.hamcrest.MatcherAssert.assertThat;
import static org.mockito.Mockito.verify;
import static org.mockito.Mockito.verifyNoMoreInteractions;
import static org.mockito.Mockito.when;

@RunWith(Parameterized.class)
public class MethodReturnTest {

    private final Class<?> type;

    private final int opcode;

    private final int sizeChange;

    @Rule
    public MethodRule mockitoRule = MockitoJUnit.rule().silent();

    @Mock
    private MethodVisitor methodVisitor;

    @Mock
    private TypeDefinition typeDefinition;

    @Mock
    private Implementation.Context implementationContext;

    public MethodReturnTest(Class<?> type, int opcode, int sizeChange) {
        this.type = type;
        this.opcode = opcode;
        this.sizeChange = sizeChange;
    }

    @Parameterized.Parameters
    public static Collection<Object[]> data() {
        return Arrays.asList(new Object[][]{
                {void.class, Opcodes.RETURN, 0},
                {Object.class, Opcodes.ARETURN, 1},
                {Object[].class, Opcodes.ARETURN, 1},
                {long.class, Opcodes.LRETURN, 2},
                {double.class, Opcodes.DRETURN, 2},
                {float.class, Opcodes.FRETURN, 1},
                {int.class, Opcodes.IRETURN, 1},
                {char.class, Opcodes.IRETURN, 1},
                {short.class, Opcodes.IRETURN, 1},
                {byte.class, Opcodes.IRETURN, 1},
                {boolean.class, Opcodes.IRETURN, 1},
        });
    }

    @Before
    public void setUp() throws Exception {
        when(typeDefinition.isPrimitive()).thenReturn(type.isPrimitive());
        when(typeDefinition.represents(type)).thenReturn(true);
    }

    @After
    public void tearDown() throws Exception {
        verifyNoMoreInteractions(implementationContext);
    }

    @Test
    public void testVoidReturn() throws Exception {
        StackManipulation stackManipulation = MethodReturn.of(typeDefinition);
        assertThat(stackManipulation.isValid(), is(true));
        StackManipulation.Size size = stackManipulation.apply(methodVisitor, implementationContext);
        assertThat(size.getSizeImpact(), is(-1 * sizeChange));
        assertThat(size.getMaximalSize(), is(0));
        verify(methodVisitor).visitInsn(opcode);
        verifyNoMoreInteractions(methodVisitor);
    }
}
