package notification

import (
	"context"

	"github.com/target/goalert/auth/authlink"
	"github.com/target/goalert/gadb"
)

// A Receiver processes incoming messages and responses.
type Receiver interface {
	// SetMessageStatus can be used to update the state of a message.
	SetMessageStatus(ctx context.Context, externalID string, status *Status) error

	// Receive records a response to a previously sent message.
	Receive(ctx context.Context, callbackID string, result Result) error

	// ReceiveSubject records a response to a previously sent message from a provider/subject (e.g. Slack user).
	ReceiveSubject(ctx context.Context, providerID, subjectID, callbackID string, result Result) error

	// AuthLinkURL will generate a URL to link a provider and subject to a GoAlert user.
	AuthLinkURL(ctx context.Context, providerID, subjectID string, meta authlink.Metadata) (string, error)

	// Start indicates a user has opted-in for notifications to this contact method.
	Start(context.Context, gadb.DestV1) error

	// Stop indicates a user has opted-out of notifications from a contact method.
	Stop(context.Context, gadb.DestV1) error

	// IsKnownDest checks if the given destination is known/not disabled.
	IsKnownDest(ctx context.Context, dest gadb.DestV1) (bool, error)
}

// UnknownSubjectError is returned from ReceiveSubject when the subject is unknown.
type UnknownSubjectError struct {
	AlertID int
}

func (e UnknownSubjectError) Error() string {
	return "unknown subject for that provider"
}