package services

import (
	"context"
	"fmt"
	corev1 "k8s.io/api/core/v1"
	apierrors "k8s.io/apimachinery/pkg/api/errors"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/client-go/tools/clientcmd"
	"opsxloki/models"
	"sort"
	"strings"
	"time"
)

type ClusterInfo struct {
	Version    string     `json:"version"`
	Nodes      []NodeInfo `json:"nodes"`
	Namespaces []string   `json:"namespaces"`
	Contexts   []string   `json:"contexts"`
	CurrentCtx string     `json:"currentContext"`
}

type NodeInfo struct {
	Name       string            `json:"name"`
	Status     string            `json:"status"`
	Roles      []string          `json:"roles"`
	Version    string            `json:"version"`
	OS         string            `json:"os"`
	Arch       string            `json:"arch"`
	InternalIP string            `json:"internalIP"`
	Labels     map[string]string `json:"labels"`
}

// GetClusterInfo 从 API Server 读取集群信息，context 列表由 kubeconfig 本地解析。
func GetClusterInfo(ctx context.Context, cluster *models.Cluster) (*ClusterInfo, error) {
	client, err := clusterClient(cluster, 30*time.Second)
	if err != nil {
		return nil, err
	}
	info := &ClusterInfo{Nodes: []NodeInfo{}, Namespaces: []string{}, Contexts: []string{}}
	if version, err := client.Discovery().ServerVersion(); err == nil {
		info.Version = version.GitVersion
	}
	nodes, err := client.CoreV1().Nodes().List(ctx, metav1.ListOptions{})
	if err != nil && !apierrors.IsForbidden(err) {
		return nil, fmt.Errorf("获取节点列表失败: %w", err)
	}
	// 命名空间级 Token 通常没有 nodes 权限：跳过节点信息，不影响集群可用性
	var nodeItems []corev1.Node
	if nodes != nil {
		nodeItems = nodes.Items
	}
	for _, item := range nodeItems {
		status := "Unknown"
		for _, cond := range item.Status.Conditions {
			if cond.Type == "Ready" {
				if cond.Status == "True" {
					status = "Ready"
				} else {
					status = "NotReady"
				}
				break
			}
		}
		roles := []string{}
		for label := range item.Labels {
			if strings.HasPrefix(label, "node-role.kubernetes.io/") {
				roles = append(roles, strings.TrimPrefix(label, "node-role.kubernetes.io/"))
			}
		}
		if len(roles) == 0 {
			roles = []string{"worker"}
		}
		sort.Strings(roles)
		ip := ""
		for _, address := range item.Status.Addresses {
			if address.Type == "InternalIP" {
				ip = address.Address
				break
			}
		}
		info.Nodes = append(info.Nodes, NodeInfo{Name: item.Name, Status: status, Roles: roles, Version: item.Status.NodeInfo.KubeletVersion, OS: item.Status.NodeInfo.OperatingSystem, Arch: item.Status.NodeInfo.Architecture, InternalIP: ip, Labels: item.Labels})
	}
	if namespaces, err := client.CoreV1().Namespaces().List(ctx, metav1.ListOptions{}); err == nil {
		for _, item := range namespaces.Items {
			info.Namespaces = append(info.Namespaces, item.Name)
		}
		sort.Strings(info.Namespaces)
	}
	source, err := resolveKubeconfig(cluster)
	if err == nil {
		if raw, err := clientcmd.Load([]byte(source)); err == nil {
			for name := range raw.Contexts {
				info.Contexts = append(info.Contexts, name)
			}
			sort.Strings(info.Contexts)
			info.CurrentCtx = raw.CurrentContext
			if cluster.Context != "" {
				info.CurrentCtx = cluster.Context
			}
		}
	}
	return info, nil
}