package disk

import (
	"fmt"
	"os/exec"
	"path/filepath"
	"strings"
)

// MapToiSCSI maps a repository to an iSCSI LUN
func (s *Service) MapToiSCSI(repoID string, targetID string, lunNumber int) error {
	s.logger.Info("Mapping repository to iSCSI", "repo", repoID, "target", targetID, "lun", lunNumber)

	repo, err := s.GetRepository(repoID)
	if err != nil {
		return err
	}

	// Get device path for the repository
	var devicePath string
	if repo.Type == "lvm" {
		// LVM device path: /dev/vgname/lvname
		devicePath = fmt.Sprintf("/dev/%s/%s", repo.VGName, repo.Name)
	} else if repo.Type == "zfs" {
		// ZFS zvol path: /dev/zvol/poolname/volname
		devicePath = fmt.Sprintf("/dev/zvol/%s/%s", repo.PoolName, repo.Name)
	} else {
		return fmt.Errorf("unsupported repository type: %s", repo.Type)
	}

	// Verify device exists
	if _, err := filepath.EvalSymlinks(devicePath); err != nil {
		return fmt.Errorf("device not found: %s", devicePath)
	}

	// The actual mapping is done by the iSCSI service
	// This is just a helper to get the device path
	return nil
}

// GetDevicePath returns the device path for a repository
func (s *Service) GetDevicePath(repoID string) (string, error) {
	repo, err := s.GetRepository(repoID)
	if err != nil {
		return "", err
	}

	if repo.Type == "lvm" {
		return fmt.Sprintf("/dev/%s/%s", repo.VGName, repo.Name), nil
	} else if repo.Type == "zfs" {
		return fmt.Sprintf("/dev/zvol/%s/%s", repo.PoolName, repo.Name), nil
	}

	return "", fmt.Errorf("unsupported repository type: %s", repo.Type)
}

// GetRepositoryInfo returns detailed information about a repository
func (s *Service) GetRepositoryInfo(repoID string) (map[string]interface{}, error) {
	repo, err := s.GetRepository(repoID)
	if err != nil {
		return nil, err
	}

	info := map[string]interface{}{
		"id":          repo.ID,
		"name":        repo.Name,
		"type":        repo.Type,
		"size":        repo.Size,
		"used":        repo.Used,
		"status":      repo.Status,
		"mount_point": repo.MountPoint,
	}

	// Get device path
	devicePath, err := s.GetDevicePath(repoID)
	if err == nil {
		info["device_path"] = devicePath
	}

	// Get filesystem info if mounted
	if repo.MountPoint != "" {
		cmd := exec.Command("df", "-h", repo.MountPoint)
		output, err := cmd.CombinedOutput()
		if err == nil {
			lines := strings.Split(string(output), "\n")
			if len(lines) > 1 {
				fields := strings.Fields(lines[1])
				if len(fields) >= 5 {
					info["filesystem"] = fields[0]
					info["total_size"] = fields[1]
					info["used_size"] = fields[2]
					info["available"] = fields[3]
					info["usage_percent"] = fields[4]
				}
			}
		}
	}

	return info, nil
}