package swarm

import (
	"sync"

	log "github.com/Sirupsen/logrus"
	"github.com/docker/swarm/cluster"
	"github.com/docker/swarm/discovery"
	"github.com/docker/swarm/scheduler"
	"github.com/docker/swarm/state"
	"github.com/samalba/dockerclient"
)

type SwarmCluster struct {
	sync.RWMutex

	nodes     *cluster.Nodes
	scheduler *scheduler.Scheduler
	options   *cluster.Options
	store     *state.Store
}

func NewCluster(scheduler *scheduler.Scheduler, store *state.Store, options *cluster.Options) cluster.Cluster {
	log.WithFields(log.Fields{"name": "swarm"}).Debug("Initializing cluster")
	return &SwarmCluster{
		nodes:     cluster.NewNodes(),
		scheduler: scheduler,
		options:   options,
		store:     store,
	}
}

// Schedule a brand new container into the cluster.
func (s *SwarmCluster) CreateContainer(config *dockerclient.ContainerConfig, name string) (*cluster.Container, error) {

	s.RLock()
	defer s.RUnlock()

	node, err := s.scheduler.SelectNodeForContainer(s.nodes.List(), config)
	if err != nil {
		return nil, err
	}

	container, err := node.Create(config, name, true)
	if err != nil {
		return nil, err
	}

	st := &state.RequestedState{
		ID:     container.Id,
		Name:   name,
		Config: config,
	}
	return container, s.store.Add(container.Id, st)
}

// Remove a container from the cluster. Containers should always be destroyed
// through the scheduler to guarantee atomicity.
func (s *SwarmCluster) RemoveContainer(container *cluster.Container, force bool) error {
	s.Lock()
	defer s.Unlock()

	if err := container.Node.Destroy(container, force); err != nil {
		return err
	}

	if err := s.store.Remove(container.Id); err != nil {
		if err == state.ErrNotFound {
			log.Debugf("Container %s not found in the store", container.Id)
			return nil
		}
		return err
	}
	return nil
}

// Entries are Docker Nodes
func (s *SwarmCluster) NewEntries(entries []*discovery.Entry) {
	for _, entry := range entries {
		go func(m *discovery.Entry) {
			if s.nodes.Get(m.String()) == nil {
				n := cluster.NewNode(m.String(), s.options.OvercommitRatio)
				if err := n.Connect(s.options.TLSConfig); err != nil {
					log.Error(err)
					return
				}
				if err := s.nodes.Add(n); err != nil {
					log.Error(err)
					return
				}
			}
		}(entry)
	}
}

func (s *SwarmCluster) Events(eventsHandler cluster.EventHandler) {
	s.nodes.Events(eventsHandler)
}

func (s *SwarmCluster) Nodes() []*cluster.Node {
	return s.nodes.List()
}

func (s *SwarmCluster) Containers() []*cluster.Container {
	return s.nodes.Containers()
}

func (s *SwarmCluster) Container(IdOrName string) *cluster.Container {
	return s.nodes.Container(IdOrName)
}