package nomino

import (
	"errors"
	"testing"
	"time"

	"github.com/google/uuid"
	"github.com/stretchr/testify/assert"
)

func TestWithGenerator(t *testing.T) {
	g := func() (string, error) { return "abc", nil }
	var c config
	WithGenerator(g)(&c)
	st, err := c.generator()
	assert.NoError(t, err)
	assert.Equal(t, "abc", st)
}

func TestMultiGeneratorInOrder(t *testing.T) {
	st1 := "abc"
	st2 := "def"
	er1 := errors.New("oops")
	g1 := func() (string, error) { return st1, nil }
	g2 := func() (string, error) { return st2, nil }
	g3 := func() (string, error) { return "", er1 }
	g := MultiGeneratorInOrder(g1, g2, g3)
	st, err := g()
	assert.NoError(t, err)
	assert.Equal(t, st1, st)
	st, err = g()
	assert.NoError(t, err)
	assert.Equal(t, st2, st)
	st, err = g()
	assert.Zero(t, st)
	assert.ErrorIs(t, err, er1)
	st, err = g()
	assert.NoError(t, err)
	assert.Equal(t, st1, st)
}

func TestMultiGeneratorInOrderOne(t *testing.T) {
	st1 := "abc"
	g1 := func() (string, error) { return st1, nil }
	g := MultiGeneratorInOrder(g1)

	st, err := g()
	assert.NoError(t, err)
	assert.Equal(t, st1, st)
	st, err = g()
	assert.NoError(t, err)
	assert.Equal(t, st1, st)
}

func TestMultiGeneratorInOrderMissing(t *testing.T) {
	g := MultiGeneratorInOrder()
	st, err := g()
	assert.Zero(t, st)
	assert.ErrorIs(t, err, ErrMissingGenerators)
	st, err = g()
	assert.Zero(t, st)
	assert.ErrorIs(t, err, ErrMissingGenerators)
}

func TestUUID(t *testing.T) {
	st, err := UUID()()
	assert.NoError(t, err)
	_, parseErr := uuid.Parse(st)
	assert.NoError(t, parseErr)
}

type badRead struct{}

func (badRead) Read([]byte) (int, error) {
	return 0, errors.New("sorry")
}

func TestUUIDFail(t *testing.T) {
	uuid.SetRand(badRead{})
	defer uuid.SetRand(nil)

	_, err := UUID()()
	assert.Equal(t, errors.New("sorry"), err)
}

func TestTimestamp(t *testing.T) {
	n := time.Now()
	st, err := Timestamp()()
	assert.NoError(t, err)
	assert.Equal(t, n.Format(FileTimestamp), st)
}

func TestTime(t *testing.T) {
	d := time.Date(1986, time.March, 28, 12, 0, 0, 0, time.UTC)

	st, err := Time(d)()
	assert.NoError(t, err)
	assert.Equal(t, d.Format(FileTimestamp), st)
}

func TestTimestampUTC(t *testing.T) {
	n := time.Now()
	st, err := TimestampUTC()()
	assert.NoError(t, err)
	assert.Equal(t, n.UTC().Format(FileTimestampNoTZ), st)
}