package vault

import (
	"encoding/base64"
	"encoding/json"
	"fmt"
	"os/exec"
	"strings"

	"github.com/Pingu-Studio/MaidnCLI/internal/utils"
)

// Constants for Vault and Kubernetes
const (
	vaultNamespace           = "vault"
	vaultPodLabelSelector    = "app.kubernetes.io/name=vault"
	vaultRootTokenSecretName = "vault-unseal-keys"
	vaultRootTokenSecretKey  = "vault-root"
	defaultVaultAddress      = "https://127.0.0.1:8200"

	// Exported constants
	GhcrSecretPath          = "secret/ghcr-auth"
	DockerHubSecretPath     = "secret/dockerhub-auth"
	GithubAuthSecretPath    = "secret/github-auth"
	OrgManagementSecretPath = "secret/org-management-pat"
	DockerConfigJSONKey     = ".dockerconfigjson"
	OrgManagementPATKey     = "ORG_MANAGEMENT_PAT"
	GhcrRegistry            = "ghcr.io"
	DockerHubRegistry       = "https://index.docker.io/v1/"
)

// DockerConfig represents the structure of a Docker config.json
type DockerConfig struct {
	Auths map[string]DockerAuth `json:"auths"`
}

// DockerAuth represents the authentication info for a Docker registry
type DockerAuth struct {
	Username string `json:"username"`
	Password string `json:"password"`
	Auth     string `json:"auth"`
}

// VaultManager handles all interactions with Kubernetes and Vault.
type VaultManager struct {
	podName   string
	rootToken string
}

// NewVaultManager creates and initializes a new VaultManager.
func NewVaultManager() (*VaultManager, error) {
	vm := &VaultManager{}

	fmt.Println("[INFO] Checking dependencies (kubectl)...")
	if !utils.CommandExists("kubectl") {
		return nil, fmt.Errorf("'kubectl' must be installed and in your PATH")
	}

	fmt.Println("[INFO] Finding Vault pod...")
	podName, err := vm.getVaultPodName()
	if err != nil {
		return nil, err
	}
	vm.podName = podName
	fmt.Printf("[INFO] Using Vault pod: %s\n", vm.podName)

	fmt.Println("[INFO] Retrieving Vault root token...")
	rootToken, err := vm.getVaultRootToken()
	if err != nil {
		return nil, err
	}
	vm.rootToken = rootToken
	fmt.Println("[SUCCESS] Found Vault root token.")

	fmt.Println("[INFO] Verifying Vault connection and token...")
	if err := vm.verifyVaultToken(); err != nil {
		return nil, fmt.Errorf("failed to validate Vault token: %w", err)
	}
	fmt.Println("[SUCCESS] Vault token is valid.")

	return vm, nil
}

func (vm *VaultManager) getVaultPodName() (string, error) {
	commonNames := []string{"vault-0", "vault-1", "vault-2"}
	for _, name := range commonNames {
		if err := utils.RunCommandQuiet("kubectl", "get", "pod", name, "-n", vaultNamespace); err == nil {
			return name, nil
		}
	}

	cmd := exec.Command("kubectl", "get", "pods", "-n", vaultNamespace, "-l", vaultPodLabelSelector, "-o", "jsonpath={.items[0].metadata.name}")
	output, err := cmd.Output()
	if err == nil && len(output) > 0 {
		return string(output), nil
	}

	return "", fmt.Errorf("could not find any running Vault pods in the '%s' namespace", vaultNamespace)
}

func (vm *VaultManager) getVaultRootToken() (string, error) {
	cmd := exec.Command("kubectl", "get", "secret", vaultRootTokenSecretName, "-n", vaultNamespace, "-o", fmt.Sprintf("jsonpath={.data.%s}", vaultRootTokenSecretKey))
	output, err := cmd.Output()
	if err != nil {
		return "", fmt.Errorf("failed to get '%s' secret from '%s' namespace: %w", vaultRootTokenSecretName, vaultNamespace, err)
	}

	if len(output) == 0 {
		return "", fmt.Errorf("key '%s' not found in secret '%s'", vaultRootTokenSecretKey, vaultRootTokenSecretName)
	}

	decoded, err := base64.StdEncoding.DecodeString(string(output))
	if err != nil {
		return "", fmt.Errorf("failed to decode base64 root token: %w", err)
	}

	return strings.TrimSpace(string(decoded)), nil
}

func (vm *VaultManager) runVaultCommandQuiet(command string) error {
	envSetup := fmt.Sprintf("export VAULT_SKIP_VERIFY=true && export VAULT_ADDR='%s' && export VAULT_TOKEN='%s'", defaultVaultAddress, vm.rootToken)
	fullCmd := fmt.Sprintf("%s && %s", envSetup, command)

	return utils.RunCommandQuiet("kubectl", "exec", "-n", vaultNamespace, vm.podName, "--", "sh", "-c", fullCmd)
}

func (vm *VaultManager) verifyVaultToken() error {
	return vm.runVaultCommandQuiet("vault token lookup")
}

// StoreSecret stores a key-value secret at the specified path in Vault quietly.
func (vm *VaultManager) StoreSecret(path string, data map[string]string) error {
	fmt.Printf("[INFO] Storing secret in Vault at path: %s...\n", path)

	var kvPairs []string
	for key, value := range data {
		escapedValue := strings.ReplaceAll(value, "'", "'\"'\"'")
		kvPairs = append(kvPairs, fmt.Sprintf("%s='%s'", key, escapedValue))
	}

	vaultCmd := fmt.Sprintf("vault kv put %s %s", path, strings.Join(kvPairs, " "))
	if err := vm.runVaultCommandQuiet(vaultCmd); err != nil {
		return fmt.Errorf("failed to store secret in Vault: %w", err)
	}

	fmt.Printf("[SUCCESS] Secret at '%s' stored successfully in Vault!\n", path)
	return nil
}

// CreateDockerConfig creates a Docker config JSON string.
func CreateDockerConfig(registry, username, token string) (string, error) {
	auth := base64.StdEncoding.EncodeToString([]byte(username + ":" + token))
	config := DockerConfig{
		Auths: map[string]DockerAuth{
			registry: {
				Username: username,
				Password: token,
				Auth:     auth,
			},
		},
	}
	configJSON, err := json.Marshal(config)
	if err != nil {
		return "", fmt.Errorf("failed to marshal docker config: %w", err)
	}
	return string(configJSON), nil
}