package torrent

import (
	"context"
	"fmt"
	"strings"
	"time"

	dockerclient "github.com/docker/docker/client"
	"github.com/rs/zerolog/log"
)

type PathMapper struct {
	containerPath string
	hostPath      string
}

func NewPathMapper(containerName string, torrentClient TorrentClient) (*PathMapper, error) {
	if containerName == "" {
		savePath, err := torrentClient.DefaultSavePath()
		if err != nil {
			return nil, fmt.Errorf("getting default save path: %w", err)
		}
		log.Info().Str("path", savePath).Msg("no container configured, using direct path")
		return &PathMapper{containerPath: savePath, hostPath: savePath}, nil
	}

	savePath, err := torrentClient.DefaultSavePath()
	if err != nil {
		return nil, fmt.Errorf("getting default save path: %w", err)
	}

	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
	defer cancel()

	cli, err := dockerclient.NewClientWithOpts(dockerclient.FromEnv, dockerclient.WithAPIVersionNegotiation())
	if err != nil {
		return nil, fmt.Errorf("creating docker client: %w", err)
	}
	defer cli.Close()

	inspect, err := cli.ContainerInspect(ctx, containerName)
	if err != nil {
		return nil, fmt.Errorf("inspecting container %s: %w", containerName, err)
	}

	hostPath := ""
	for _, mount := range inspect.Mounts {
		if mount.Destination == savePath {
			hostPath = mount.Source
			break
		}
	}

	if hostPath == "" {
		return nil, fmt.Errorf("no mount found for %s in container %s", savePath, containerName)
	}

	log.Info().
		Str("container", containerName).
		Str("container_path", savePath).
		Str("host_path", hostPath).
		Msg("resolved download path mapping")

	return &PathMapper{containerPath: savePath, hostPath: hostPath}, nil
}

func (m *PathMapper) ToHost(containerPath string) string {
	if m.containerPath == m.hostPath {
		return containerPath
	}
	return strings.Replace(containerPath, m.containerPath, m.hostPath, 1)
}

func (m *PathMapper) ToContainer(hostPath string) string {
	if m.containerPath == m.hostPath {
		return hostPath
	}
	return strings.Replace(hostPath, m.hostPath, m.containerPath, 1)
}

func (m *PathMapper) HostDownloadPath() string {
	return m.hostPath
}

func (m *PathMapper) ContainerDownloadPath() string {
	return m.containerPath
}