/*
Copyright 2014 Google Inc. All rights reserved.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

package client

import (
	"errors"
	"fmt"

	"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
	"github.com/GoogleCloudPlatform/kubernetes/pkg/fields"
	"github.com/GoogleCloudPlatform/kubernetes/pkg/labels"
	"github.com/GoogleCloudPlatform/kubernetes/pkg/watch"
)

// ServicesNamespacer has methods to work with Service resources in a namespace
type ServicesNamespacer interface {
	Services(namespace string) ServiceInterface
}

// ServiceInterface has methods to work with Service resources.
type ServiceInterface interface {
	List(selector labels.Selector) (*api.ServiceList, error)
	Get(name string) (*api.Service, error)
	Create(srv *api.Service) (*api.Service, error)
	Update(srv *api.Service) (*api.Service, error)
	Delete(name string) error
	Watch(label labels.Selector, field fields.Selector, resourceVersion string) (watch.Interface, error)
}

// services implements PodsNamespacer interface
type services struct {
	r  *Client
	ns string
}

// newServices returns a PodsClient
func newServices(c *Client, namespace string) *services {
	return &services{c, namespace}
}

// List takes a selector, and returns the list of services that match that selector
func (c *services) List(selector labels.Selector) (result *api.ServiceList, err error) {
	result = &api.ServiceList{}
	err = c.r.Get().
		Namespace(c.ns).
		Resource("services").
		LabelsSelectorParam(api.LabelSelectorQueryParam(c.r.APIVersion()), selector).
		Do().
		Into(result)
	return
}

// Get returns information about a particular service.
func (c *services) Get(name string) (result *api.Service, err error) {
	if len(name) == 0 {
		return nil, errors.New("name is required parameter to Get")
	}

	result = &api.Service{}
	err = c.r.Get().Namespace(c.ns).Resource("services").Name(name).Do().Into(result)
	return
}

// Create creates a new service.
func (c *services) Create(svc *api.Service) (result *api.Service, err error) {
	result = &api.Service{}
	// v1beta3 does not allow POST without a namespace.
	needNamespace := !api.PreV1Beta3(c.r.APIVersion())
	namespace := c.ns
	if needNamespace && len(namespace) == 0 {
		namespace = api.NamespaceDefault
	}
	err = c.r.Post().Namespace(namespace).Resource("services").Body(svc).Do().Into(result)
	return
}

// Update updates an existing service.
func (c *services) Update(svc *api.Service) (result *api.Service, err error) {
	result = &api.Service{}
	if len(svc.ResourceVersion) == 0 {
		err = fmt.Errorf("invalid update object, missing resource version: %v", svc)
		return
	}
	// v1beta3 does not allow PUT without a namespace.
	needNamespace := !api.PreV1Beta3(c.r.APIVersion())
	namespace := c.ns
	if needNamespace && len(namespace) == 0 {
		namespace = api.NamespaceDefault
	}
	err = c.r.Put().Namespace(namespace).Resource("services").Name(svc.Name).Body(svc).Do().Into(result)
	return
}

// Delete deletes an existing service.
func (c *services) Delete(name string) error {
	// v1beta3 does not allow DELETE without a namespace.
	needNamespace := !api.PreV1Beta3(c.r.APIVersion())
	namespace := c.ns
	if needNamespace && len(namespace) == 0 {
		namespace = api.NamespaceDefault
	}
	return c.r.Delete().Namespace(c.ns).Resource("services").Name(name).Do().Error()
}

// Watch returns a watch.Interface that watches the requested services.
func (c *services) Watch(label labels.Selector, field fields.Selector, resourceVersion string) (watch.Interface, error) {
	return c.r.Get().
		Prefix("watch").
		Namespace(c.ns).
		Resource("services").
		Param("resourceVersion", resourceVersion).
		LabelsSelectorParam(api.LabelSelectorQueryParam(c.r.APIVersion()), label).
		FieldsSelectorParam(api.FieldSelectorQueryParam(c.r.APIVersion()), field).
		Watch()
}