package common

import (
	"strconv"

	"github.com/cri-o/ocicni/pkg/ocicni"
	"github.com/docker/go-connections/nat"
	"github.com/pkg/errors"
)

// createPortBindings iterates ports mappings and exposed ports into a format CNI understands
func createPortBindings(ports []string) ([]ocicni.PortMapping, error) {
	// TODO wants someone to rewrite this code in the future
	var portBindings []ocicni.PortMapping
	// The conversion from []string to natBindings is temporary while mheon reworks the port
	// deduplication code.  Eventually that step will not be required.
	_, natBindings, err := nat.ParsePortSpecs(ports)
	if err != nil {
		return nil, err
	}
	for containerPb, hostPb := range natBindings {
		var pm ocicni.PortMapping
		pm.ContainerPort = int32(containerPb.Int())
		for _, i := range hostPb {
			var hostPort int
			var err error
			pm.HostIP = i.HostIP
			if i.HostPort == "" {
				hostPort = containerPb.Int()
			} else {
				hostPort, err = strconv.Atoi(i.HostPort)
				if err != nil {
					return nil, errors.Wrapf(err, "unable to convert host port to integer")
				}
			}

			pm.HostPort = int32(hostPort)
			pm.Protocol = containerPb.Proto()
			portBindings = append(portBindings, pm)
		}
	}
	return portBindings, nil
}