package main

import (
	auditV1 "audit-schema/gen/go/audit/v1"
	"context"
	"github.com/google/uuid"
	"google.golang.org/protobuf/proto"
)

// AuditApi is the interface to log audit events.
//
// It provides a Log method that can be used to validate and directly send events.
// If the transactional outbox patter should be used, the ValidateAndSerialize and Send methods
// can be called manually to decouple operations.
type AuditApi interface {

	// Log is a convenience method that validates, serializes and sends data over the wire.
	// If the transactional outbox patter should be used, the ValidateAndSerialize method
	// and Send method can be called manually.
	//
	//  Parameters:
	//  * ctx - the context object
	//  * event - the auditV1.AuditEvent
	//  * visibility - route the event only internally or to the customer (not evaluated in the legacy solution)
	//  * routingIdentifier - the identifier for the AMQP-Topic selection (optional)
	//    * auditV1.ObjectType_OBJECT_TYPE_ORGANIZATION
	//    * auditV1.ObjectType_OBJECT_TYPE_PROJECT
	//  * objectIdentifier - the identifier of the object (optional - if not folder must be identical to routingIdentifier)
	//    * auditV1.ObjectType_OBJECT_TYPE_ORGANIZATION
	//    * auditV1.ObjectType_OBJECT_TYPE_FOLDER
	//    * auditV1.ObjectType_OBJECT_TYPE_PROJECT
	//
	// It may return one of the following errors:
	/*
		- ErrEventNil - if event is nil
		- ErrObjectIdentifierVisibilityMismatch - if object identifier and visibility are not in a valid state
		- ErrRoutableIdentifierMissing - if routing identifier type and object identifier type do not match
		- ErrRoutableIdentifierTypeMismatch - if routing identifier type and object identifier types are not compatible
		- ErrUnsupportedObjectIdentifierType - if an unsupported object identifier type was provided
		- ErrUnsupportedResourceReferenceType - if an unsupported resource reference type was provided
		- protovalidate.ValidationError - if schema validation errors have been detected
		- protobuf serialization errors - if the event couldn't be serialized
	*/
	Log(ctx context.Context, event *auditV1.AuditEvent, visibility auditV1.Visibility, routingIdentifier *RoutingIdentifier, objectIdentifier *auditV1.ObjectIdentifier) error

	// ValidateAndSerialize validates and serializes the event into a byte representation.
	// The result has to be sent explicitly by calling the Send method.
	ValidateAndSerialize(event *auditV1.AuditEvent, visibility auditV1.Visibility, routingIdentifier *RoutingIdentifier, objectIdentifier *auditV1.ObjectIdentifier) (SerializedPayload, error)

	// Send the serialized content as byte array to the audit log system.
	Send(ctx context.Context, routingIdentifier *RoutingIdentifier, serializedPayload *SerializedPayload) error
}

// ProtobufValidator is an abstraction for validators.
// Concrete implementations are e.g. protovalidate.Validator
type ProtobufValidator interface {
	Validate(msg proto.Message) error
}

// SerializedPayload is an abstraction for serialized content
type SerializedPayload interface {

	// GetPayload returns the actual payload as byte array
	GetPayload() []byte

	// GetContentType returns the content type of the payload
	GetContentType() string
}

// RoutingIdentifierType is an enumeration of allowed identifier types.
type RoutingIdentifierType int

// RoutingIdentifierType enumeration values.
const (
	RoutingIdentifierTypeOrganization RoutingIdentifierType = 0
	RoutingIdentifierTypeProject      RoutingIdentifierType = 1
)

// RoutingIdentifier is a representation for identifiers of allowed types.
type RoutingIdentifier struct {
	Identifier uuid.UUID
	Type       RoutingIdentifierType
}