// Package docker — lapisan tipis di atas Docker SDK untuk core tia.
// Bebas UI: dipakai bersama oleh TUI dan CLI (F-028).
package docker

import (
	"context"
	"fmt"
	"io"
	"strconv"
	"strings"

	"github.com/docker/docker/api/types/container"
	"github.com/docker/docker/api/types/image"
	"github.com/docker/docker/api/types/network"
	"github.com/docker/docker/api/types/volume"
	"github.com/docker/docker/client"
)

// Client — pembungkus Docker SDK dengan negosiasi versi API
// (mendukung Docker Engine 20.10+ DAN Podman dengan API kompatibel-Docker).
type Client struct {
	cli *client.Client
}

func (c *Client) Close() error { return c.cli.Close() }

// Info — ringkasan daemon untuk dashboard, doctor, dan status bar.
type Info struct {
	ServerVersion string
	APIVersion    string
	Containers    int
	Running       int
	Images        int
	MemoryTotal   int64
	CPUs          int
}

func (c *Client) Info(ctx context.Context) (Info, error) {
	i, err := c.cli.Info(ctx)
	if err != nil {
		return Info{}, fmt.Errorf("docker: info: %w", err)
	}
	return Info{
		ServerVersion: i.ServerVersion,
		APIVersion:    c.cli.ClientVersion(), // hasil negosiasi API
		Containers:    i.Containers,
		Running:       i.ContainersRunning,
		Images:        i.Images,
		MemoryTotal:   i.MemTotal,
		CPUs:          i.NCPU,
	}, nil
}

// Ping — cek daemon hidup (dipakai doctor).
func (c *Client) Ping(ctx context.Context) error {
	if _, err := c.cli.Ping(ctx); err != nil {
		return fmt.Errorf("docker: ping: %w", err)
	}
	return nil
}

// Container — ringkasan kontainer untuk sidebar/dashboard.
type Container struct {
	ID      string
	ImageID string // id image lengkap (untuk menandai image yang dipakai)
	Name    string
	Image   string
	State   string // running, exited, paused, restarting, created, dead
	Status  string // "Up 2 hours (healthy)"
}

// ListContainers mengembalikan semua kontainer (termasuk yang berhenti).
func (c *Client) ListContainers(ctx context.Context) ([]Container, error) {
	list, err := c.cli.ContainerList(ctx, container.ListOptions{All: true})
	if err != nil {
		return nil, fmt.Errorf("docker: container list: %w", err)
	}
	out := make([]Container, 0, len(list))
	for _, ct := range list {
		name := ""
		if len(ct.Names) > 0 {
			name = strings.TrimPrefix(ct.Names[0], "/")
		}
		id := ct.ID
		if len(id) > 12 {
			id = id[:12]
		}
		out = append(out, Container{
			ID:      id,
			ImageID: ct.ImageID,
			Name:    name,
			Image:   ct.Image,
			State:   ct.State,
			Status:  ct.Status,
		})
	}
	return out, nil
}

// Image — ringkasan image untuk daftar.
type Image struct {
	ID      string // 12 char tanpa prefix sha256:
	Tags    []string
	Size    int64
	Created int64 // unix
}

func (c *Client) ListImages(ctx context.Context) ([]Image, error) {
	list, err := c.cli.ImageList(ctx, image.ListOptions{})
	if err != nil {
		return nil, fmt.Errorf("docker: image list: %w", err)
	}
	out := make([]Image, 0, len(list))
	for _, im := range list {
		tags := im.RepoTags
		if len(tags) == 1 && tags[0] == "<none>:<none>" {
			tags = nil
		}
		out = append(out, Image{
			ID:      trimID(im.ID),
			Tags:    tags,
			Size:    im.Size,
			Created: im.Created,
		})
	}
	return out, nil
}

// Volume — ringkasan volume.
type Volume struct {
	Name       string
	Driver     string
	Mountpoint string
}

func (c *Client) ListVolumes(ctx context.Context) ([]Volume, error) {
	resp, err := c.cli.VolumeList(ctx, volume.ListOptions{})
	if err != nil {
		return nil, fmt.Errorf("docker: volume list: %w", err)
	}
	out := make([]Volume, 0, len(resp.Volumes))
	for _, v := range resp.Volumes {
		out = append(out, Volume{Name: v.Name, Driver: v.Driver, Mountpoint: v.Mountpoint})
	}
	return out, nil
}

// Network — ringkasan jaringan (subnet pertama dari IPAM).
type Network struct {
	ID     string
	Name   string
	Driver string
	Scope  string
	Subnet string
}

func (c *Client) ListNetworks(ctx context.Context) ([]Network, error) {
	list, err := c.cli.NetworkList(ctx, network.ListOptions{})
	if err != nil {
		return nil, fmt.Errorf("docker: network list: %w", err)
	}
	out := make([]Network, 0, len(list))
	for _, n := range list {
		subnet := ""
		for _, cfg := range n.IPAM.Config {
			if cfg.Subnet != "" {
				subnet = cfg.Subnet
				break
			}
		}
		out = append(out, Network{
			ID:     trimID(n.ID),
			Name:   n.Name,
			Driver: n.Driver,
			Scope:  n.Scope,
			Subnet: subnet,
		})
	}
	return out, nil
}

// trimID — buang prefix sha256: dan potong ke 12 karakter.
func trimID(s string) string {
	s = strings.TrimPrefix(s, "sha256:")
	if len(s) > 12 {
		s = s[:12]
	}
	return s
}

// StreamLogs membuka stream log kontainer (follow). Pemanggil wajib Close.
// Stream mentah: kontainer TTY tidak dibungkus header multiplex.
func (c *Client) StreamLogs(ctx context.Context, id string, tail int, timestamps bool) (io.ReadCloser, error) {
	rc, err := c.cli.ContainerLogs(ctx, id, container.LogsOptions{
		ShowStdout: true,
		ShowStderr: true,
		Follow:     true,
		Tail:       strconv.Itoa(tail),
		Timestamps: timestamps,
	})
	if err != nil {
		return nil, fmt.Errorf("docker: stream log: %w", err)
	}
	return rc, nil
}

// ContainerTty — apakah kontainer punya TTY (menentukan perlu demux atau tidak).
func (c *Client) ContainerTty(ctx context.Context, id string) (bool, error) {
	in, err := c.cli.ContainerInspect(ctx, id)
	if err != nil {
		return false, fmt.Errorf("docker: inspect: %w", err)
	}
	return in.Config != nil && in.Config.Tty, nil
}