package creature

import "testing"

func runMachineTest(program []int, test *testing.T) (machine *Machine) {
	machine = &Machine { Program: program }

	err := machine.Execute(0)
	if err != nil {
		test.Log("machine exited with error:", err)
		test.Fail()
	}

	return
}

func TestPush(test *testing.T) {
	machine := runMachineTest ([]int {
		PUSH, 654,
	}, test)
	
	result := machine.Pop()
	test.Log("popped:", result)

	if result != 654 {
		test.Log("result should be", 654)
		test.Fail()
	}
}

func TestArithmetic(test *testing.T) {
	machine := runMachineTest([]int {
		PUSH, 2,
		PUSH, 3,
		ADD,
		
		PUSH, 4,
		PUSH, 10,
		SUB,
		
		PUSH, 7,
		PUSH, 2,
		MUL,
		
		PUSH, 3,
		PUSH, 12,
		DIV,
		
		PUSH, 6,
		PUSH, 8,
		MOD,
	}, test)

	modResult := machine.Pop()
	divResult := machine.Pop()
	mulResult := machine.Pop()
	subResult := machine.Pop()
	addResult := machine.Pop()

	test.Log("add:", addResult)
	test.Log("sub:", subResult)
	test.Log("mul:", mulResult)
	test.Log("div:", divResult)
	test.Log("mod:", modResult)

	if addResult != 5 {
		test.Log("add result should be", 5)
		test.Fail()
	}

	if subResult != 6 {
		test.Log("sub result should be", 6)
		test.Fail()
	}

	if mulResult != 14 {
		test.Log("mul result should be", 14)
		test.Fail()
	}

	if divResult != 4 {
		test.Log("div result should be", 4)
		test.Fail()
	}

	if modResult != 2 {
		test.Log("mod result should be", 2)
		test.Fail()
	}
}

func TestComparison(test *testing.T) {
	machine := runMachineTest([]int {
		PUSH, 6,
		PUSH, 6,
		EQ,
		
		PUSH, 4,
		PUSH, 324,
		GT,
		
		PUSH, 324,
		PUSH, 4,
		LT,
		
		PUSH, 6,
		PUSH, 54,
		NEQ,
		
	}, test)

	neqResult := machine.Pop()
	ltResult := machine.Pop()
	gtResult := machine.Pop()
	eqResult := machine.Pop()

	test.Log("eq:", eqResult)
	test.Log("gt:", gtResult)
	test.Log("lt:", ltResult)
	test.Log("neq:", neqResult)

	if eqResult != 1 {
		test.Log("eq result should be", 1)
		test.Fail()
	}

	if gtResult != 1 {
		test.Log("gt result should be", 1)
		test.Fail()
	}

	if ltResult != 1 {
		test.Log("lt result should be", 1)
		test.Fail()
	}

	if neqResult != 1 {
		test.Log("neq result should be", 1)
		test.Fail()
	}
}