package containers

import (
	"archive/tar"
	"context"
	"errors"
	"fmt"
	"sync"

	"github.com/docker/docker/api/types"
	"github.com/docker/go-connections/nat"
)

var (
	_               Container = (*containerRef)(nil)
	ErrNoMappedPort           = errors.New("no mapped port found")
)

type containerRef struct {
	info         types.ContainerJSON
	shutdowner   Shutdowner
	client       Client
	resourceName string
	containerID  string
	networkID    string
	inspectOnce  sync.Once
}

func (c *containerRef) CopyFileFromContainer(ctx context.Context, path string, f CopyContainerFileHandler) (err error) {
	reader, _, err := c.client.CopyFromContainer(ctx, c.containerID, path)
	if err != nil {
		return err
	}

	defer func() {
		err = errors.Join(err, reader.Close())
	}()

	tarReader := tar.NewReader(reader)

	var header *tar.Header
	for header, err = tarReader.Next(); err == nil; header, err = tarReader.Next() {
		if err := f(header, tarReader); err != nil {
			return err
		}
	}

	return nil
}

func (c *containerRef) NetworkID() string {
	return c.networkID
}

func (c *containerRef) ID() string {
	return c.containerID
}

func (c *containerRef) MappedPort(ctx context.Context, port nat.Port) (hostIP, hostPort string, err error) {
	c.inspectOnce.Do(func() {
		c.info, err = c.client.ContainerInspect(ctx, c.containerID)
	})

	if err != nil {
		return "", "", err
	}

	binding, ok := c.info.NetworkSettings.Ports[port]
	if !ok || len(binding) == 0 {
		return "", "", fmt.Errorf("%w: %s", ErrNoMappedPort, port.Port())
	}

	return binding[0].HostIP, binding[0].HostPort, nil
}

func (c *containerRef) Shutdown(ctx context.Context) error {
	return c.shutdowner.ShutdownContainer(ctx, c)
}