package api

import (
	"encoding/base64"
	"testing"

	"github.com/stretchr/testify/assert"

	pkgAuditCommon "dev.azure.com/schwarzit/schwarzit.stackit-public/audit-go.git/pkg/audit/common"
)

func Test_ToBase64(t *testing.T) {

	t.Run("cloud event nil", func(t *testing.T) {
		var cloudEvent *pkgAuditCommon.CloudEvent = nil
		routableIdentifier := pkgAuditCommon.RoutableSystemIdentifier

		base64str, err := ToBase64(cloudEvent, routableIdentifier)
		assert.ErrorIs(t, err, pkgAuditCommon.ErrCloudEventNil)
		assert.Nil(t, base64str)
	})

	t.Run("routable identifier nil", func(t *testing.T) {
		cloudEvent := &pkgAuditCommon.CloudEvent{}
		var routableIdentifier *pkgAuditCommon.RoutableIdentifier = nil

		base64str, err := ToBase64(cloudEvent, routableIdentifier)
		assert.ErrorIs(t, err, ErrRoutableIdentifierNil)
		assert.Nil(t, base64str)
	})

	t.Run("encoded event", func(t *testing.T) {
		e := &pkgAuditCommon.CloudEvent{}
		r := pkgAuditCommon.RoutableSystemIdentifier
		base64str, err := ToBase64(e, r)
		assert.NoError(t, err)

		cloudEvent, routableIdentifier, err := FromBase64(*base64str)
		assert.NoError(t, err)
		assert.Equal(t, e, cloudEvent)
		assert.Equal(t, r, routableIdentifier)
	})
}

func Test_FromBase64(t *testing.T) {

	t.Run("empty string", func(t *testing.T) {
		cloudEvent, routableIdentifier, err := FromBase64("")
		assert.ErrorIs(t, err, ErrBase64StringEmpty)
		assert.Nil(t, cloudEvent)
		assert.Nil(t, routableIdentifier)
	})

	t.Run("without version suffix", func(t *testing.T) {
		cloudEvent, routableIdentifier, err := FromBase64("ey")
		assert.ErrorIs(t, err, ErrUnsupportedBase64StringVersion)
		assert.Nil(t, cloudEvent)
		assert.Nil(t, routableIdentifier)
	})

	t.Run("no base64 string", func(t *testing.T) {
		cloudEvent, routableIdentifier, err := FromBase64("no base 64 v1")
		assert.EqualError(t, err, "illegal base64 data at input byte 2")
		assert.Nil(t, cloudEvent)
		assert.Nil(t, routableIdentifier)
	})

	t.Run("no json serialized event", func(t *testing.T) {
		base64Str := base64.StdEncoding.EncodeToString([]byte("not expected"))
		base64Str = base64Str + base64AuditEventV1
		cloudEvent, routableIdentifier, err := FromBase64(base64Str)
		assert.EqualError(t, err, "invalid character 'o' in literal null (expecting 'u')")
		assert.Nil(t, cloudEvent)
		assert.Nil(t, routableIdentifier)
	})

	t.Run("decoded event", func(t *testing.T) {
		e := &pkgAuditCommon.CloudEvent{}
		r := pkgAuditCommon.RoutableSystemIdentifier
		base64str, err := ToBase64(e, r)
		assert.NoError(t, err)

		cloudEvent, routableIdentifier, err := FromBase64(*base64str)
		assert.NoError(t, err)
		assert.Equal(t, e, cloudEvent)
		assert.Equal(t, r, routableIdentifier)
	})
}