package k8s

import (
	"context"
	"flag"
	"fmt"
	"log"
	"math/rand"
	"path/filepath"
	"strconv"

	"basic.com/aps/aps_deploy.git/src/util"
	appsv1 "k8s.io/api/apps/v1"
	apiv1 "k8s.io/api/core/v1"
	"k8s.io/apimachinery/pkg/api/errors"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/util/intstr"
	"k8s.io/client-go/kubernetes"
	"k8s.io/client-go/tools/clientcmd"
)

var (
	replicas      int32 = 3
	port          int32 = 9081
	rpcPort       int32 = 9091
	namespaces          = []string{"guangsheng", "geruimi", "tongsheng"}
	usedNodePorts       = make(map[int32]bool)
)

func create_test() {
	// 配置 Kubernetes 集群的 kubeconfig 路径
	kubeconfig := flag.String("kubeconfig", filepath.Join(util.HomeDir(), ".kube", "config"), "kubeconfig file")
	flag.Parse()

	// 创建 Kubernetes 客户端
	config, err := clientcmd.BuildConfigFromFlags("", *kubeconfig)
	if err != nil {
		panic(err.Error())
	}

	clientset, err := kubernetes.NewForConfig(config)
	if err != nil {
		panic(err.Error())
	}

	// 创建多个 Namespace 下的相同名称的 Deployment 和 Service
	for _, ns := range namespaces {
		err = CreateDeploymentAndService(clientset, ns, ns, ns)
		if err != nil {
			panic(err)
		}

		nodeport, err := GetServiceNodePort(clientset, ns, ns)
		if err != nil {
			panic(err)
		}

		log.Printf("Service NodePort: %d\n", nodeport)
	}
}

// CheckAndDeleteResources 检测并删除指定的 Namespace、Deployment 和 Service
func CheckAndDeleteResources(clientset *kubernetes.Clientset, namespace, deploymentName, serviceName string) error {
	fmt.Println("\033[1;37;40mChecking and deleting resources in Namespace:", namespace, "\033[0m")

	// 检查并删除 Deployment
	err := deleteDeploymentIfExists(clientset, namespace, deploymentName)
	if err != nil {
		return err
	}

	// 检查并删除 Service
	err = deleteServiceIfExists(clientset, namespace, serviceName)
	if err != nil {
		return err
	}

	return nil
}

// deleteDeploymentIfExists 检查并删除指定的 Deployment（如果存在）
func deleteDeploymentIfExists(clientset *kubernetes.Clientset, namespace, deploymentName string) error {
	fmt.Println("\033[1;37;40mChecking and deleting Deployment:", deploymentName, "\033[0m")

	err := clientset.AppsV1().Deployments(namespace).Delete(context.TODO(), deploymentName, metav1.DeleteOptions{})
	if err != nil {
		if errors.IsNotFound(err) {
			fmt.Printf("Deployment %s not found in Namespace %s\n", deploymentName, namespace)
		} else {
			return fmt.Errorf("failed to delete Deployment: %v", err)
		}
	} else {
		fmt.Printf("Deployment %s deleted from Namespace %s\n", deploymentName, namespace)
	}

	return nil
}

// deleteServiceIfExists 检查并删除指定的 Service（如果存在）
func deleteServiceIfExists(clientset *kubernetes.Clientset, namespace, serviceName string) error {
	fmt.Println("\033[1;37;40mChecking and deleting Service:", serviceName, "\033[0m")

	err := clientset.CoreV1().Services(namespace).Delete(context.TODO(), serviceName, metav1.DeleteOptions{})
	if err != nil {
		if errors.IsNotFound(err) {
			fmt.Printf("Service %s not found in Namespace %s\n", serviceName, namespace)
		} else {
			return fmt.Errorf("failed to delete Service: %v", err)
		}
	} else {
		fmt.Printf("Service %s deleted from Namespace %s\n", serviceName, namespace)
	}

	return nil
}

func CreateDeploymentAndService(clientset *kubernetes.Clientset, namespace, deploymentName, serviceName string) error {
	fmt.Println("\033[1;37;40mCreating resources in Namespace:", namespace, "\033[0m")

	// 检测并删除已存在的 Deployment 和 Service
	err := CheckAndDeleteResources(clientset, namespace, deploymentName, serviceName)
	if err != nil {
		return err
	}

	// 创建 Namespace
	err = createNamespace(clientset, namespace)
	if err != nil {
		return err
	}

	nodePort1, nodePort2, err := getTwoNodePort(clientset)
	if err != nil {
		return err
	}

	port1 := fmt.Sprint(nodePort1)
	port2 := fmt.Sprint(nodePort2)
	// 创建 Deployment
	err = createDeployment(clientset, namespace, deploymentName, port1, port2)
	if err != nil {
		return err
	}

	log.Printf("Waiting for Deployment %s to be ready...\n", deploymentName)
	// 创建 Service
	err = createService(clientset, namespace, serviceName, nodePort1, nodePort2)
	if err != nil {
		return err
	}

	return nil
}

// createNamespace 创建指定的 Namespace
func createNamespace(clientset *kubernetes.Clientset, namespace string) error {
	log.Printf("Creating Namespace: %s\n", namespace)

	ns := &apiv1.Namespace{
		ObjectMeta: metav1.ObjectMeta{
			Name: namespace,
		},
	}

	_, err := clientset.CoreV1().Namespaces().Create(context.TODO(), ns, metav1.CreateOptions{})
	if err != nil {
		if !errors.IsAlreadyExists(err) {
			return fmt.Errorf("failed to create Namespace: %w", err)
		}
		log.Printf("Namespace %s already exists\n", namespace)
	} else {
		log.Printf("Namespace %s created\n", namespace)
	}

	return nil
}

func createDeployment(clientset *kubernetes.Clientset, namespace, deploymentName, port1, port2 string) error {
	fmt.Println("\033[1;37;40mCreating Deployment:", deploymentName, "\033[0m")

	deployment := &appsv1.Deployment{
		ObjectMeta: metav1.ObjectMeta{
			Name: deploymentName,
		},
		Spec: appsv1.DeploymentSpec{
			Replicas: &replicas,
			Selector: &metav1.LabelSelector{
				MatchLabels: map[string]string{
					"cid": namespace,
				},
			},
			Template: apiv1.PodTemplateSpec{
				ObjectMeta: metav1.ObjectMeta{
					Labels: map[string]string{
						"cid": namespace,
					},
				},
				Spec: apiv1.PodSpec{
					TopologySpreadConstraints: []apiv1.TopologySpreadConstraint{
						{
							MaxSkew:           1,
							TopologyKey:       "kubernetes.io/hostname",
							WhenUnsatisfiable: apiv1.DoNotSchedule,
							LabelSelector: &metav1.LabelSelector{
								MatchLabels: map[string]string{
									"cid": namespace,
								},
							},
						},
					},
					Containers: []apiv1.Container{
						{
							Name:  namespace,
							Image: "192.168.20.119/apsserver/apsserver:v0.5",
							Env: []apiv1.EnvVar{
								{
									Name:  "NODE_PORT1",
									Value: port1,
								},
								{
									Name:  "NODE_PORT2",
									Value: port2,
								},
								{
									Name:  "DB_HOST",
									Value: "localhost",
								},
								{
									Name:  "DB_NAME",
									Value: namespace,
								},
								{
									Name:  "DB_PORT",
									Value: strconv.Itoa(3306),
								},
								{
									Name:  "DB_USER",
									Value: namespace,
								},
								{
									Name:  "DB_PASSWD",
									Value: namespace + "@Basic2023",
								},
							},
							ImagePullPolicy: apiv1.PullAlways, // 设置镜像拉取策略为 Always
						},
					},
				},
			},
		},
	}

	_, err := clientset.AppsV1().Deployments(namespace).Create(context.TODO(), deployment, metav1.CreateOptions{})
	if err != nil {
		if !errors.IsAlreadyExists(err) {
			return fmt.Errorf("failed to create Deployment: %v", err)
		}
		fmt.Printf("Deployment %s already exists in Namespace %s\n", deploymentName, namespace)
	} else {
		fmt.Printf("Deployment %s created in Namespace %s\n", deploymentName, namespace)
	}

	return nil
}

// createService 创建指定的 Service
func createService(clientset *kubernetes.Clientset, namespace, serviceName string, port1, port2 int32) error {
	fmt.Println("\033[1;37;40mCreating Service:", serviceName, "\033[0m")

	service := &apiv1.Service{
		ObjectMeta: metav1.ObjectMeta{
			Name: serviceName,
		},
		Spec: apiv1.ServiceSpec{
			Selector: map[string]string{
				"cid": namespace,
			},
			Type: apiv1.ServiceTypeNodePort,
			Ports: []apiv1.ServicePort{
				{
					Name:       "http",
					Protocol:   apiv1.ProtocolTCP,
					Port:       port,                      // 集群内部访问端口
					TargetPort: intstr.FromInt(int(port)), // 容器对外端口
					NodePort:   port1,                     // 外部访问端口
				},
				{
					Name:       "tcp",
					Protocol:   apiv1.ProtocolTCP,
					Port:       rpcPort,
					TargetPort: intstr.FromInt(int(rpcPort)),
					NodePort:   port2,
				},
			},
		},
	}

	_, err := clientset.CoreV1().Services(namespace).Create(context.TODO(), service, metav1.CreateOptions{})

	if err != nil {
		if !errors.IsAlreadyExists(err) {
			return fmt.Errorf("failed to create Service: %v", err)
		}
		log.Printf("Service %s already exists in Namespace %s\n", serviceName, namespace)
	} else {
		log.Printf("Service %s created in Namespace %s\n", serviceName, namespace)
	}

	return nil
}

func getTwoNodePort(client *kubernetes.Clientset) (nodePort1, nodePort2 int32, err error) {
	nodePort1, err = getRandomNodePort(client)
	if err != nil {
		return 0, 0, err
	}

	for {
		nodePort2, err = getRandomNodePort(client)
		if err != nil {
			return 0, 0, err
		}

		if nodePort2 != nodePort1 {
			break
		}

	}

	return nodePort1, nodePort2, nil
}

// getRandomNodePort 获取一个未使用的随机 NodePort
func getRandomNodePort(clientset *kubernetes.Clientset) (int32, error) {
	// 获取一个随机的 NodePort
	nodePort := int32(0)
	for {
		// 生成一个随机的 NodePort
		nodePort = generateRandomNodePort()

		// 检查该 NodePort 是否已被使用
		used, err := isNodePortUsed(clientset, nodePort)
		if err != nil {
			return 0, err

		}

		// 如果未被使用，则标记为已使用，并退出循环
		if !used {
			usedNodePorts[nodePort] = true
			break
		}
	}

	return nodePort, nil
}

// generateRandomNodePort 生成一个随机的 NodePort
func generateRandomNodePort() int32 {
	// 在范围 30000-32767 中生成随机数作为 NodePort
	return int32(rand.Intn(32767-30000+1) + 30000)
}

// isNodePortUsed 检查指定的 NodePort 是否已被使用
func isNodePortUsed(clientset *kubernetes.Clientset, nodePort int32) (bool, error) {
	// 获取所有 Service
	services, err := clientset.CoreV1().Services("").List(context.TODO(), metav1.ListOptions{})
	if err != nil {
		return false, err
	}

	// 检查每个 Service 的 NodePort 是否与指定的 NodePort 相同
	for _, svc := range services.Items {
		for _, port := range svc.Spec.Ports {
			if port.NodePort == nodePort {
				return true, nil
			}
		}
	}

	return false, nil
}

// GetServiceNodePort 获取指定 Service 的 NodePort
func GetServiceNodePort(clientset *kubernetes.Clientset, namespace, serviceName string) (int32, error) {
	svc, err := clientset.CoreV1().Services(namespace).Get(context.TODO(), serviceName, metav1.GetOptions{})
	if err != nil {
		return 0, fmt.Errorf("failed to get Service: %v", err)
	}

	// 检查 Service 类型是否为 NodePort
	if svc.Spec.Type != apiv1.ServiceTypeNodePort {
		return 0, fmt.Errorf("Service %s is not of type NodePort", serviceName)
	}

	// 获取第一个端口的 NodePort
	if len(svc.Spec.Ports) > 0 {
		for _, p := range svc.Spec.Ports {
			// return tcp port
			if p.Name == "tcp" {
				return p.NodePort, nil
			}
		}
	}

	return 0, fmt.Errorf("no ports defined for Service %s", serviceName)
}