package cli

import (
	"archive/tar"
	"bytes"
	"context"
	"encoding/json"
	"errors"
	"fmt"
	"io"
	"log"
	"net/http"
	"path/filepath"
	"strconv"
	"strings"

	// used for replacing abra code
	"coopcloud.tech/abra/pkg/app"
	"coopcloud.tech/abra/pkg/client"
	"coopcloud.tech/abra/pkg/config"
	containerPkg "coopcloud.tech/abra/pkg/container"
	"coopcloud.tech/abra/pkg/i18n"
	"coopcloud.tech/abra/pkg/service"
	"github.com/docker/docker/api/types"
	containertypes "github.com/docker/docker/api/types/container"
	"github.com/docker/docker/api/types/filters"
	dockerClient "github.com/docker/docker/client"

	"github.com/docker/docker/api/types/container"
	"github.com/docker/docker/pkg/stdcopy"
)

func (h *abraHandler) pingBackupBot(w http.ResponseWriter, r *http.Request, server string) {
	cl, err := client.New(server)
	if err != nil {
		InternalServerError(w, err)
	}

	_, err = RetrieveBackupBotContainer(cl)
	if err != nil {
		InternalServerError(w, err)
	}
	w.WriteHeader(http.StatusOK)
}
func (h *abraHandler) handleBackupCreateApp(w http.ResponseWriter, r *http.Request, appName string) {
	log.Printf("Handling App Backup!")
	args := []string{}

	_, err := handleBackupCommand(appName, args, "create")
	if err != nil {
		InternalServerError(w, err)
	}

	log.Printf("Finishing app backup!")
	w.WriteHeader(http.StatusOK)
}

func (h *abraHandler) handleBackupRestoreApp(w http.ResponseWriter, r *http.Request, appName string) {
	log.Printf("Handling Backup Restore!")

	args := []string{}
	d := json.NewDecoder(r.Body)
	d.DisallowUnknownFields()

	body := struct {
		Snapshot *string `json:"snapshot"`
	}{}
	err := d.Decode(&body)
	if err != nil {
		log.Printf("error: %v", err)
		BadRequest(w, err)
		return
	}
	if body.Snapshot != nil {
		args = append(args, fmt.Sprintf("SNAPSHOT=%s", *body.Snapshot))
	}
	args = append(args, fmt.Sprintf("NONINTERACTIVE=%v", true))
	_, err = handleBackupCommand(appName, args, "restore")
	if err != nil {
		InternalServerError(w, err)
	}

	log.Printf("Finishing app restore!")
	w.WriteHeader(http.StatusOK)
}

func (h *abraHandler) handleBackupListApp(w http.ResponseWriter, r *http.Request, appName string) {
	log.Printf("Handling App List Backup!")
	args := []string{}
	output, err := handleBackupCommand(appName, args, "snapshots")
	if err != nil {
		InternalServerError(w, err)
	}
	snapshots := strings.Split(output, "\n")
	resp := []AppSnapshot{}
	for _, snapshot := range snapshots {
		items := strings.Split(snapshot, " ")
		if len(items) < 3 {
			break
		}
		resp = append(resp, AppSnapshot{
			CreatedAt: items[0],
			Snapshot:  items[1],
			Version:   items[2],
		})
	}
	jsonBytes, err := json.Marshal(resp)
	if err != nil {
		InternalServerError(w, err)
		return
	}

	w.Header().Set("Content-Type", "application/json")
	w.WriteHeader(http.StatusOK)
	w.Write(jsonBytes)
}
func (h *abraHandler) handleBackupDownloadSnapshot(w http.ResponseWriter, r *http.Request, appName string) {
	log.Printf("Handling Snapshot Download!")
	app, err := app.Get(appName)
	if err != nil {
		InternalServerError(w, err)
	}
	cl, err := client.New(app.Server)
	if err != nil {
		InternalServerError(w, err)
	}

	targetContainer, err := RetrieveBackupBotContainer(cl)
	if err != nil {
		InternalServerError(w, err)
	}

	execEnv := []string{
		fmt.Sprintf("SERVICE=%s", app.Domain),
		"MACHINE_LOGS=true",
	}
	// TODO: add args
	_, err = RunBackupCmdRemote(cl, "download", targetContainer.ID, execEnv)
	if err != nil {
		InternalServerError(w, err)
	}

	remoteBackupDir := "/tmp/backup.tar.gz"
	content, size, err := CopyFromContainer(cl, targetContainer.ID, remoteBackupDir)
	if err != nil {
		InternalServerError(w, fmt.Errorf("error copying from container: %v", err))
	}
	defer content.Close()

	w.Header().Set("Content-type", "application/x-tar")
	tr := tar.NewReader(content)
	for {
		header, err := tr.Next()
		if err == io.EOF {
			break
		}
		if err != nil {
			InternalServerError(w, err)
		}
		if filepath.Base(header.Name) == "backup.tar.gz" {
			w.Header().Set(
				"Content-Disposition",
				`attachment; filename="backup.tar.gz"`,
			)
			w.Header().Set("Content-Type", "application/gzip")
			w.Header().Set(
				"Content-Length",
				strconv.FormatInt(size, 10),
			)
			if _, err := io.Copy(w, tr); err != nil {
				InternalServerError(w, err)
			}
			return
		}
	}
}

func handleBackupCommand(appName string, args []string, action string) (string, error) {
	app, err := app.Get(appName)
	if err != nil {
		return "", err
	}
	cl, err := client.New(app.Server)
	if err != nil {
		return "", err
	}

	targetContainer, err := RetrieveBackupBotContainer(cl)
	if err != nil {
		return "", err
	}

	execEnv := []string{
		fmt.Sprintf("SERVICE=%s", app.Domain),
		"MACHINE_LOGS=true",
	}
	for _, arg := range args {
		execEnv = append(execEnv, arg)
	}
	output, err := RunBackupCmdRemote(cl, action, targetContainer.ID, execEnv)
	if err != nil {
		return "", err
	}
	return output, nil
}

// copied from https://git.coopcloud.tech/toolshed/abra/src/branch/main/cli/internal/backup.go
// tty is set to false
func RunBackupCmdRemote(
	cl *dockerClient.Client,
	backupCmd string,
	containerID string,
	execEnv []string) (string, error) {
	execBackupListOpts := containertypes.ExecOptions{
		AttachStderr: true,
		AttachStdout: true,
		Cmd:          []string{"/usr/bin/backup", "--", backupCmd},
		Env:          execEnv,
		Tty:          false,
	}

	stdout, err := Exec(context.Background(), cl, containerID, &execBackupListOpts)
	log.Printf("stdout: %v | err: %v", stdout, err)
	if err != nil {
		return "", err
	}
	return stdout, nil
}

func RetrieveBackupBotContainer(cl *dockerClient.Client) (types.Container, error) {
	ctx := context.Background()
	chosenService, err := service.GetServiceByLabel(ctx, cl, config.BackupbotLabel, true)
	if err != nil {
		return types.Container{}, errors.New(i18n.G("no backupbot discovered, is it deployed?"))
	}

	filters := filters.NewArgs()
	filters.Add("name", chosenService.Spec.Name)
	targetContainer, err := containerPkg.GetContainer(
		ctx,
		cl,
		filters,
		true,
	)
	if err != nil {
		return types.Container{}, err
	}

	return targetContainer, nil
}

func Exec(ctx context.Context, cli *dockerClient.Client, containerID string, execOptions *container.ExecOptions) (string, error) {
	execResp, err := cli.ContainerExecCreate(ctx, containerID, *execOptions)
	if err != nil {
		return "", err
	}

	resp, err := cli.ContainerExecAttach(ctx, execResp.ID, container.ExecStartOptions{
		Tty: false,
	})
	if err != nil {
		return "", err
	}
	defer resp.Close()

	var stdout, stderr bytes.Buffer

	_, err = stdcopy.StdCopy(&stdout, &stderr, resp.Reader)
	if err != nil {
		return "", err
	}

	inspect, err := cli.ContainerExecInspect(ctx, execResp.ID)
	if err != nil {
		return "", err
	}

	if inspect.ExitCode != 0 {
		return stdout.String(),
			fmt.Errorf("command exited with status %d and error %s", inspect.ExitCode, stderr.String())
	}

	return stdout.String(), nil
}