// Package runtime is a service runtime manager
package runtime

import "fmt"

const (
	TypeNamespace     = "namespace"
	TypeNetworkPolicy = "networkpolicy"
	TypeService       = "service"
)

// Resource represents any resource handled by runtime
type Resource interface {
	String() string
	Type() string
}

// Namespace represents a logical namespace for organising resources
type Namespace struct {
	// Name of the namespace
	Name string
}

// NewNamespace mints a new namespace
func NewNamespace(name string) (*Namespace, error) {
	if name == "" {
		return nil, ErrInvalidResource
	}
	return &Namespace{
		Name: name,
	}, nil
}

// String implements Resource
func (r *Namespace) String() string {
	return r.Name
}

// Type implements Resource
func (*Namespace) Type() string {
	return TypeNamespace
}

// NetworkPolicy represents an ACL of label pairs allowing ignress to a namespace
type NetworkPolicy struct {
	// The labels allowed ingress by this policy
	AllowedLabels map[string]string
	// Name of the network policy
	Name string
	// Namespace the network policy belongs to
	Namespace string
}

// NewNetworkPolicy mints a new networkpolicy
func NewNetworkPolicy(name, namespace string, allowedLabels map[string]string) (*NetworkPolicy, error) {
	if name == "" || namespace == "" {
		return nil, ErrInvalidResource
	}
	if allowedLabels == nil {
		allowedLabels = map[string]string{
			"origin": "micro",
		}
	}
	return &NetworkPolicy{
		AllowedLabels: allowedLabels,
		Name:          name,
		Namespace:     namespace,
	}, nil
}

// String implements Resource
func (r *NetworkPolicy) String() string {
	return fmt.Sprintf("%s.%s", r.Namespace, r.Name)
}

// Type implements Resource
func (*NetworkPolicy) Type() string {
	return TypeNetworkPolicy
}

// Service represents a Micro service running within a namespace
type Service struct {
	// Name of the service
	Name string
	// Version of the service
	Version string
	// url location of source
	Source string
	// Metadata stores metadata
	Metadata map[string]string
	// Status of the service
	Status ServiceStatus
}

// NewService mints a new service
func NewService(name, version string) (*Service, error) {
	if name == "" {
		return nil, ErrInvalidResource
	}
	if version == "" {
		version = "latest"
	}
	return &Service{
		Name:    name,
		Version: version,
	}, nil
}

// String implements Resource
func (r *Service) String() string {
	return fmt.Sprintf("service://%s@%s:%s", r.Metadata["namespace"], r.Name, r.Version)
}

// Type implements Resource
func (*Service) Type() string {
	return TypeService
}