package services

import (
	"fmt"
	"os"
	"regexp"

	"lokideploy/models"
)

// resolveKubeconfig 取集群最终的 kubeconfig 文本（优先内存字段，其次磁盘文件）
func resolveKubeconfig(cluster *models.Cluster) (string, error) {
	if cluster.KubeConfig != "" {
		return cluster.KubeConfig, nil
	}
	if cluster.KubeConfigPath != "" {
		data, err := os.ReadFile(cluster.KubeConfigPath)
		if err != nil {
			return "", fmt.Errorf("读取 kubeconfig 文件失败: %v", err)
		}
		return string(data), nil
	}
	return "", fmt.Errorf("集群未配置 kubeconfig")
}

// BuildKubeconfigFromToken 用 API Server + Token 构造最小 kubeconfig
// 采用 insecure-skip-tls-verify，便于内网/自签证书集群接入
func BuildKubeconfigFromToken(apiServer, token string) string {
	return fmt.Sprintf(`apiVersion: v1
kind: Config
clusters:
- cluster:
    insecure-skip-tls-verify: true
    server: %s
  name: loki-cluster
contexts:
- context:
    cluster: loki-cluster
    user: loki-user
  name: loki-context
current-context: loki-context
users:
- name: loki-user
  user:
    token: %s
`, apiServer, token)
}

var apiServerRe = regexp.MustCompile(`(?m)^\s*server:\s*(\S+)`)

// ExtractAPIServer 从 kubeconfig 文本提取 server 地址（展示用）
func ExtractAPIServer(kubeconfig string) string {
	m := apiServerRe.FindStringSubmatch(kubeconfig)
	if len(m) >= 2 {
		return m[1]
	}
	return ""
}