package com.loomcom.symon;

import com.loomcom.symon.devices.Memory;
import org.junit.Test;

import static junit.framework.TestCase.assertFalse;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertTrue;

/**
 * Test for Zero Page Indirect addressing mode, found on some instructions
 * in the 65C02 and 65816
 */
public class CpuZeroPageIndirectTest {
    protected Cpu    cpu;
    protected Bus    bus;
    protected Memory mem;

    private void makeCmosCpu() throws Exception {
        makeCpu(InstructionTable.CpuBehavior.CMOS_6502);
    }

    private void makeNmosCpu() throws Exception {
        makeCpu(InstructionTable.CpuBehavior.NMOS_6502);
    }

    private void makeCpu(InstructionTable.CpuBehavior behavior) throws Exception {
        this.cpu = new Cpu(behavior);
        this.bus = new Bus(0x0000, 0xffff);
        this.mem = new Memory(0x0000, 0xffff);
        bus.addCpu(cpu);
        bus.addDevice(mem);

        // Load the reset vector.
        bus.write(0xfffc, Bus.DEFAULT_LOAD_ADDRESS & 0x00ff);
        bus.write(0xfffd, (Bus.DEFAULT_LOAD_ADDRESS & 0xff00) >>> 8);

        cpu.reset();
    }

    @Test
    public void test_ora() throws Exception {
        makeCmosCpu();

        // Set some initial values in zero page.
        bus.write(0x30, 0x00);
        bus.write(0x31, 0x10);

        bus.write(0x40, 0x01);
        bus.write(0x41, 0x10);

        bus.write(0x50, 0x02);
        bus.write(0x51, 0x10);

        bus.write(0x60, 0x03);
        bus.write(0x61, 0x10);

        bus.write(0x1000, 0x11);
        bus.write(0x1001, 0x22);
        bus.write(0x1002, 0x44);
        bus.write(0x1003, 0x88);

        bus.loadProgram(0x12, 0x30,  // ORA ($30)
                        0x12, 0x40,  // ORA ($40)
                        0x12, 0x50,  // ORA ($50)
                        0x12, 0x60); // ORA ($60)


        assertEquals(0x00, cpu.getAccumulator());

        // 0x00 | 0x11 = 0x11
        cpu.step();
        assertEquals(0x11, cpu.getAccumulator());
        assertFalse(cpu.getZeroFlag());
        assertFalse(cpu.getNegativeFlag());

        // 0x11 | 0x22 = 0x33
        cpu.step();
        assertEquals(0x33, cpu.getAccumulator());
        assertFalse(cpu.getZeroFlag());
        assertFalse(cpu.getNegativeFlag());

        // 0x33 | 0x44 = 0x77
        cpu.step();
        assertEquals(0x77, cpu.getAccumulator());
        assertFalse(cpu.getZeroFlag());
        assertFalse(cpu.getNegativeFlag());

        // 0x77 | 0x88 = 0xff
        cpu.step();
        assertEquals(0xff, cpu.getAccumulator());
        assertFalse(cpu.getZeroFlag());
        assertTrue(cpu.getNegativeFlag());
    }

    @Test
    public void test_ora_requiresCmosCpu() throws Exception {
        makeNmosCpu();

        // Set some initial values in zero page.
        bus.write(0x30, 0x00);
        bus.write(0x31, 0x10);

        bus.write(0x40, 0x01);
        bus.write(0x41, 0x10);

        bus.write(0x50, 0x02);
        bus.write(0x51, 0x10);

        bus.write(0x60, 0x03);
        bus.write(0x61, 0x10);

        bus.write(0x1000, 0x11);
        bus.write(0x1001, 0x22);
        bus.write(0x1002, 0x44);
        bus.write(0x1003, 0x88);

        bus.loadProgram(0x12, 0x30,  // ORA ($30)
                        0x12, 0x40,  // ORA ($40)
                        0x12, 0x50,  // ORA ($50)
                        0x12, 0x60); // ORA ($60)


        assertEquals(0x00, cpu.getAccumulator());

        boolean zState = cpu.getZeroFlag();
        boolean nState = cpu.getNegativeFlag();

        // 0x00 | 0x11 = 0x11, but not implemented in NMOS cpu
        cpu.step();
        assertEquals(0x00, cpu.getAccumulator());
        assertEquals(zState, cpu.getZeroFlag());         // unchanged
        assertEquals(nState, cpu.getNegativeFlag());     // unchanged

        // 0x11 | 0x22 = 0x33, but not implemented in NMOS cpu
        cpu.step();
        assertEquals(0x00, cpu.getAccumulator());
        assertEquals(zState, cpu.getZeroFlag());         // unchanged
        assertEquals(nState, cpu.getNegativeFlag());     // unchanged

        // 0x33 | 0x44 = 0x77, but not implemented in NMOS cpu
        cpu.step();
        assertEquals(0x00, cpu.getAccumulator());
        assertEquals(zState, cpu.getZeroFlag());         // unchanged
        assertEquals(nState, cpu.getNegativeFlag());     // unchanged

        // 0x77 | 0x88 = 0xff, but not implemented in NMOS cpu
        cpu.step();
        assertEquals(0x00, cpu.getAccumulator());
        assertEquals(zState, cpu.getZeroFlag());         // unchanged
        assertEquals(nState, cpu.getNegativeFlag());     // unchanged
    }

    @Test
    public void test_and() throws Exception {
        makeCmosCpu();

        // Set some initial values in zero page.
        bus.write(0x30, 0x00);
        bus.write(0x31, 0x10);

        bus.write(0x40, 0x01);
        bus.write(0x41, 0x10);

        bus.write(0x50, 0x02);
        bus.write(0x51, 0x10);

        bus.write(0x1000, 0x33);
        bus.write(0x1001, 0x11);
        bus.write(0x1002, 0x88);

        bus.loadProgram(0x32, 0x30,  // AND ($30)
                        0x32, 0x40,  // AND ($40)
                        0x32, 0x50); // AND ($50)

        cpu.setAccumulator(0xff);

        // 0xFF & 0x33 == 0x33
        cpu.step();
        assertEquals(0x33, cpu.getAccumulator());
        assertFalse(cpu.getZeroFlag());
        assertFalse(cpu.getNegativeFlag());

        // 0x33 & 0x11 == 0x11
        cpu.step();
        assertEquals(0x11, cpu.getAccumulator());
        assertFalse(cpu.getZeroFlag());
        assertFalse(cpu.getNegativeFlag());

        // 0x11 & 0x80 == 0
        cpu.step();
        assertEquals(0, cpu.getAccumulator());
        assertTrue(cpu.getZeroFlag());
        assertFalse(cpu.getNegativeFlag());
    }

    @Test
    public void test_and_requiresCmosCpu() throws Exception {
        makeNmosCpu();

        // Set some initial values in zero page.
        bus.write(0x30, 0x00);
        bus.write(0x31, 0x10);

        bus.write(0x40, 0x01);
        bus.write(0x41, 0x10);

        bus.write(0x50, 0x02);
        bus.write(0x51, 0x10);

        bus.write(0x1000, 0x33);
        bus.write(0x1001, 0x11);
        bus.write(0x1002, 0x88);

        bus.loadProgram(0x32, 0x30,  // AND ($30)
                        0x32, 0x40,  // AND ($40)
                        0x32, 0x50); // AND ($50)


        cpu.setAccumulator(0xff);

        boolean zState = cpu.getZeroFlag();
        boolean nState = cpu.getNegativeFlag();

        // 0xFF & 0x33 == 0x33, but not implemented in NMOS cpu
        cpu.step();
        assertEquals(0xff, cpu.getAccumulator());
        assertEquals(zState, cpu.getZeroFlag());
        assertEquals(nState, cpu.getNegativeFlag());

        // 0x33 & 0x11 == 0x11, but not implemented in NMOS cpu
        cpu.step();
        assertEquals(0xff, cpu.getAccumulator());
        assertEquals(zState, cpu.getZeroFlag());
        assertEquals(nState, cpu.getNegativeFlag());

        // 0x11 & 0x80 == 0, but not implemented in NMOS cpu
        cpu.step();
        assertEquals(0xff, cpu.getAccumulator());
        assertEquals(zState, cpu.getZeroFlag());
        assertEquals(nState, cpu.getNegativeFlag());
    }

    @Test
    public void test_eor() throws Exception {
        makeCmosCpu();

        // Set some initial values in zero page.
        bus.write(0x30, 0x00);
        bus.write(0x31, 0x10);

        bus.write(0x40, 0x01);
        bus.write(0x41, 0x10);

        bus.write(0x50, 0x02);
        bus.write(0x51, 0x10);

        bus.write(0x60, 0x03);
        bus.write(0x61, 0x10);

        bus.write(0x1000, 0x00);
        bus.write(0x1001, 0xff);
        bus.write(0x1002, 0x33);
        bus.write(0x1003, 0x44);

        bus.loadProgram(0x52, 0x30,  // AND ($30)
                        0x52, 0x40,  // AND ($40)
                        0x52, 0x50,  // EOR ($50)
                        0x52, 0x60); // AND ($60)


        cpu.setAccumulator(0x88);

        cpu.step();
        assertEquals(0x88, cpu.getAccumulator());

        cpu.step();
        assertEquals(0x77, cpu.getAccumulator());

        cpu.step();
        assertEquals(0x44, cpu.getAccumulator());

        cpu.step();
        assertEquals(0x00, cpu.getAccumulator());
    }

    @Test
    public void test_eor_requiresCmosCpu() throws Exception {
        makeNmosCpu();

        // Set some initial values in zero page.
        bus.write(0x30, 0x00);
        bus.write(0x31, 0x10);

        bus.write(0x40, 0x01);
        bus.write(0x41, 0x10);

        bus.write(0x50, 0x02);
        bus.write(0x51, 0x10);

        bus.write(0x60, 0x03);
        bus.write(0x61, 0x10);

        bus.write(0x1000, 0x00);
        bus.write(0x1001, 0xff);
        bus.write(0x1002, 0x33);
        bus.write(0x1003, 0x44);

        bus.loadProgram(0x52, 0x30,  // AND ($30)
                        0x52, 0x40,  // AND ($40)
                        0x52, 0x50,  // EOR ($50)
                        0x52, 0x60); // AND ($60)


        cpu.setAccumulator(0x88);

        cpu.step();
        assertEquals(0x88, cpu.getAccumulator());

        cpu.step();
        assertEquals(0x88, cpu.getAccumulator());

        cpu.step();
        assertEquals(0x88, cpu.getAccumulator());

        cpu.step();
        assertEquals(0x88, cpu.getAccumulator());
    }
}