package composetransform

import (
	composetypes "github.com/aanand/compose-file/types"
	"github.com/docker/docker/api/types"
	networktypes "github.com/docker/docker/api/types/network"
)

const (
	labelNamespace = "com.docker.stack.namespace"
)

// Namespace mangles names by prepending the name
type Namespace struct {
	name string
}

// Scope prepends the namespace to a name
func (n Namespace) Scope(name string) string {
	return n.name + "_" + name
}

// AddStackLabel returns labels with the namespace label added
func AddStackLabel(namespace Namespace, labels map[string]string) map[string]string {
	if labels == nil {
		labels = make(map[string]string)
	}
	labels[labelNamespace] = namespace.name
	return labels
}

type networks map[string]composetypes.NetworkConfig

// ConvertNetworks from the compose-file type to the engine API type
func ConvertNetworks(
	namespace Namespace,
	networks networks,
	servicesNetworks map[string]struct{},
) (map[string]types.NetworkCreate, []string) {
	if networks == nil {
		networks = make(map[string]composetypes.NetworkConfig)
	}

	externalNetworks := []string{}
	result := make(map[string]types.NetworkCreate)

	for internalName := range servicesNetworks {
		network := networks[internalName]
		if network.External.External {
			externalNetworks = append(externalNetworks, network.External.Name)
			continue
		}

		createOpts := types.NetworkCreate{
			Labels:  AddStackLabel(namespace, network.Labels),
			Driver:  network.Driver,
			Options: network.DriverOpts,
		}

		if network.Ipam.Driver != "" || len(network.Ipam.Config) > 0 {
			createOpts.IPAM = &networktypes.IPAM{}
		}

		if network.Ipam.Driver != "" {
			createOpts.IPAM.Driver = network.Ipam.Driver
		}
		for _, ipamConfig := range network.Ipam.Config {
			config := networktypes.IPAMConfig{
				Subnet: ipamConfig.Subnet,
			}
			createOpts.IPAM.Config = append(createOpts.IPAM.Config, config)
		}
		result[internalName] = createOpts
	}

	return result, externalNetworks
}