package controller

import (
	"fmt"
	"io/ioutil"

	"bitbucket.org/lightcodelabs/ingress/internal/caddy"
	"k8s.io/api/extensions/v1beta1"
)

// onResourceAdded runs when an ingress resource is added to the cluster.
func (c *CaddyController) onResourceAdded(obj interface{}) {
	c.syncQueue.Add(ResourceAddedAction{
		resource: obj,
	})
}

// onResourceUpdated is run when an ingress resource is updated in the cluster.
func (c *CaddyController) onResourceUpdated(old interface{}, new interface{}) {
	c.syncQueue.Add(ResourceUpdatedAction{
		resource:    new,
		oldResource: old,
	})
}

// onResourceDeleted is run when an ingress resource is deleted from the cluster.
func (c *CaddyController) onResourceDeleted(obj interface{}) {
	c.syncQueue.Add(ResourceDeletedAction{
		resource: obj,
	})
}

// onSyncStatus is run every sync interval to update the source address on ingresses.
func (c *CaddyController) onSyncStatus(obj interface{}) {
	c.syncQueue.Add(SyncStatusAction{})
}

// Action is an interface for ingress actions
type Action interface {
	handle(c *CaddyController) error
}

// ResourceAddedAction provides an implementation of the action interface
type ResourceAddedAction struct {
	resource interface{}
}

// ResourceUpdatedAction provides an implementation of the action interface
type ResourceUpdatedAction struct {
	resource    interface{}
	oldResource interface{}
}

// ResourceDeletedAction provides an implementation of the action interface
type ResourceDeletedAction struct {
	resource interface{}
}

func (r ResourceAddedAction) handle(c *CaddyController) error {
	// configure caddy to handle this resource
	ing, ok := r.resource.(*v1beta1.Ingress)
	if !ok {
		return fmt.Errorf("ResourceAddedAction: incoming resource is not of type ingress")
	}

	// get current caddy config for rollback purposes
	oldConfig := *c.resourceStore.CaddyConfig
	fmt.Fprint(ioutil.Discard, oldConfig)

	// update internal caddy config with new ingress info
	newConfig, err := caddy.AddIngressConfig(c.resourceStore.CaddyConfig, ing)
	if err != nil {
		return err
	}

	// TODO :- reload caddy2 config with newConfig
	fmt.Fprint(ioutil.Discard, newConfig)

	// TODO :- if err rollback to old config

	// ensure that ingress source is updated to point to this ingress controller's ip
	c.syncStatus([]*v1beta1.Ingress{ing})

	c.resourceStore.AddIngress(ing)

	// ~~~~
	// when updating caddy config the ingress controller should bypass kube-proxy and get the ip address of
	// the pod that the deployment we are proxying to is running on so that we can proxy to that ip address port.
	// this is good for session affinity and increases performance (since we don't have to hit dns).

	// example getting an ingress
	// ingClient := c.kubeClient.ExtensionsV1beta1().Ingresses(c.namespace) // get a client to update the ingress
	// ingClient.UpdateStatus(ing) // pass an ingress with the status.address field updated
	// ~~~

	return nil
}

func (r ResourceUpdatedAction) handle(c *CaddyController) error {
	// find the caddy config related to the oldResource and update it

	fmt.Printf("\nUpdated resource:\n +%v\n\nOld resource: \n %+v\n", r.resource, r.oldResource)

	return nil
}

func (r ResourceDeletedAction) handle(c *CaddyController) error {
	// delete all resources from caddy config that are associated with this resource
	// reload caddy config

	fmt.Printf("\nDeleted resource:\n +%v\n", r.resource)

	return nil
}