package ut

import (
	"errors"
	"testing"

	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
)

type optional struct {
	err  error
	exec bool
}

func (o *optional) Invoke() error {
	o.exec = true
	return o.err
}

func TestDeopterInvoked(t *testing.T) {
	var o = &optional{}
	var d = NewDeopter(o.Invoke)

	var err = d.Invoke()

	assert.Nil(t, err)
	assert.True(t, o.exec)
}

func TestDeopterOptOut(t *testing.T) {
	var o = &optional{}
	var d = NewDeopter(o.Invoke)

	d.Deopt()
	var err = d.Invoke()

	assert.Nil(t, err)
	assert.False(t, o.exec)
}

func TestDeopterErrorOnInvocation(t *testing.T) {
	var o = &optional{err: errors.New("err")}
	var d = NewDeopter(o.Invoke)

	var err = d.Invoke()

	assert.Equal(t, o.err, err)
}

func TestDeopterMultipleInvocations(t *testing.T) {
	var o1, o2 = &optional{}, &optional{}
	var d = NewDeopter(o1.Invoke, o2.Invoke)

	var err = d.Invoke()

	assert.Nil(t, err)
	assert.True(t, o1.exec)
	assert.True(t, o2.exec)
}

func TestDeopterMultipleErrors(t *testing.T) {
	var o1, o2 = &optional{err: errors.New("err1")}, &optional{err: errors.New("err2")}
	var d = NewDeopter(o1.Invoke, o2.Invoke)

	var err = d.Invoke()

	assert.NotNil(t, err)
	require.IsType(t, &Errors{}, err)
	var errs = err.(*Errors).Errs
	require.Equal(t, 2, len(errs))
	assert.True(t, o1.exec)
	assert.True(t, o2.exec)
}

func TestDeopterCanAdd(t *testing.T) {
	var o1, o2 = &optional{}, &optional{}
	var d = NewDeopter(o1.Invoke)

	d.Add(o2.Invoke)

	var err = d.Invoke()
	assert.Nil(t, err)
	assert.True(t, o1.exec)
	assert.True(t, o2.exec)
}