package updater

import (
	"context"
	"fmt"
	"os"
	"strconv"
	"strings"

	"coopcloud.tech/abra/cli/internal"
	appPkg "coopcloud.tech/abra/pkg/app"
	"coopcloud.tech/abra/pkg/client"
	"coopcloud.tech/abra/pkg/envfile"
	"coopcloud.tech/abra/pkg/lint"
	"coopcloud.tech/abra/pkg/recipe"
	"coopcloud.tech/abra/pkg/upstream/convert"
	"coopcloud.tech/abra/pkg/upstream/stack"
	"coopcloud.tech/tagcmp"
	charmLog "github.com/charmbracelet/log"
	composetypes "github.com/docker/cli/cli/compose/types"
	"github.com/docker/docker/api/types"
	"github.com/docker/docker/api/types/filters"
	dockerclient "github.com/docker/docker/client"
	"github.com/spf13/cobra"

	"coopcloud.tech/abra/pkg/log"
)

const SERVER = "localhost"

// NotifyCommand checks for available upgrades.
var NotifyCommand = &cobra.Command{
	Use:     "notify [flags]",
	Aliases: []string{"n"},
	Short:   "Check for available upgrades",
	Long: `Notify on new versions for deployed apps.

If a new patch/minor version is available, a notification is printed.

Use "--major/-m" to include new major versions.`,
	Args: cobra.NoArgs,
	Run: func(cmd *cobra.Command, args []string) {
		cl, err := client.New("default")
		if err != nil {
			log.Fatal(err)
		}

		stacks, err := stack.GetStacks(cl)
		if err != nil {
			log.Fatal(err)
		}

		for _, stackInfo := range stacks {
			stackName := stackInfo.Name
			recipeName, err := getLabel(cl, stackName, "recipe")
			if err != nil {
				log.Fatal(err)
			}

			if recipeName != "" {
				_, err = getLatestUpgrade(cl, stackName, recipeName)
				if err != nil {
					log.Fatal(err)
				}
			}
		}
	},
}

// UpgradeCommand upgrades apps.
var UpgradeCommand = &cobra.Command{
	Use:     "upgrade [[stack] [recipe] | --all] [flags]",
	Aliases: []string{"u"},
	Short:   "Upgrade apps",
	Long: `Upgrade an app by specifying stack name and recipe. 

Use "--all" to upgrade every deployed app.

For each app with auto updates enabled, the deployed version is compared with
the current recipe catalogue version. If a new patch/minor version is
available, the app is upgraded.

To include major versions use the "--major/-m" flag. You probably don't want
that as it will break things. Only apps that are not deployed with "--chaos/-C"
are upgraded, to update chaos deployments use the "--chaos/-C" flag. Use it
with care.`,
	Args: cobra.RangeArgs(0, 2),
	// TODO(d1): complete stack/recipe
	// ValidArgsFunction: func(
	// 	cmd *cobra.Command,
	// 	args []string,
	// 	toComplete string) ([]string, cobra.ShellCompDirective) {
	// },
	Run: func(cmd *cobra.Command, args []string) {
		cl, err := client.New("default")
		if err != nil {
			log.Fatal(err)
		}

		if !updateAll && len(args) != 2 {
			log.Fatal("missing arguments or --all/-a flag")
		}

		if !updateAll {
			stackName := args[0]
			recipeName := args[1]

			err = tryUpgrade(cl, stackName, recipeName)
			if err != nil {
				log.Fatal(err)
			}

			return
		}

		stacks, err := stack.GetStacks(cl)
		if err != nil {
			log.Fatal(err)
		}

		for _, stackInfo := range stacks {
			stackName := stackInfo.Name
			recipeName, err := getLabel(cl, stackName, "recipe")
			if err != nil {
				log.Fatal(err)
			}

			err = tryUpgrade(cl, stackName, recipeName)
			if err != nil {
				log.Fatal(err)
			}
		}
	},
}

// getLabel reads docker labels from running services in the format of "coop-cloud.${STACK_NAME}.${LABEL}".
func getLabel(cl *dockerclient.Client, stackName string, label string) (string, error) {
	filter := filters.NewArgs()
	filter.Add("label", fmt.Sprintf("%s=%s", convert.LabelNamespace, stackName))

	services, err := cl.ServiceList(context.Background(), types.ServiceListOptions{Filters: filter})
	if err != nil {
		return "", err
	}

	for _, service := range services {
		labelKey := fmt.Sprintf("coop-cloud.%s.%s", stackName, label)
		if labelValue, ok := service.Spec.Labels[labelKey]; ok {
			return labelValue, nil
		}
	}

	log.Debugf("no %s label found for %s", label, stackName)

	return "", nil
}

// getBoolLabel reads a boolean docker label from running services
func getBoolLabel(cl *dockerclient.Client, stackName string, label string) (bool, error) {
	lableValue, err := getLabel(cl, stackName, label)
	if err != nil {
		return false, err
	}

	if lableValue != "" {
		value, err := strconv.ParseBool(lableValue)
		if err != nil {
			return false, err
		}

		return value, nil
	}

	log.Debugf("boolean label %s could not be found for %s, set default to false.", label, stackName)

	return false, nil
}

// getEnv reads env variables from docker services.
func getEnv(cl *dockerclient.Client, stackName string) (envfile.AppEnv, error) {
	envMap := make(map[string]string)
	filter := filters.NewArgs()
	filter.Add("label", fmt.Sprintf("%s=%s", convert.LabelNamespace, stackName))

	services, err := cl.ServiceList(context.Background(), types.ServiceListOptions{Filters: filter})
	if err != nil {
		return nil, err
	}

	for _, service := range services {
		envList := service.Spec.TaskTemplate.ContainerSpec.Env
		for _, envString := range envList {
			splitString := strings.SplitN(envString, "=", 2)
			if len(splitString) != 2 {
				log.Debugf("can't separate key from value: %s (this variable is probably unset)", envString)
				continue
			}
			k := splitString[0]
			v := splitString[1]
			log.Debugf("for %s read env %s with value: %s from docker service", stackName, k, v)
			envMap[k] = v
		}
	}

	return envMap, nil
}

// getLatestUpgrade returns the latest available version for an app respecting
// the "--major" flag if it is newer than the currently deployed version.
func getLatestUpgrade(cl *dockerclient.Client, stackName string, recipeName string) (string, error) {
	deployedVersion, err := getDeployedVersion(cl, stackName, recipeName)
	if err != nil {
		return "", err
	}

	availableUpgrades, err := getAvailableUpgrades(cl, stackName, recipeName, deployedVersion)
	if err != nil {
		return "", err
	}

	if len(availableUpgrades) == 0 {
		log.Debugf("no available upgrades for %s", stackName)
		return "", nil
	}

	var chosenUpgrade string
	if len(availableUpgrades) > 0 {
		chosenUpgrade = availableUpgrades[len(availableUpgrades)-1]
		log.Infof("%s (%s) can be upgraded from version %s to %s", stackName, recipeName, deployedVersion, chosenUpgrade)
	}

	return chosenUpgrade, nil
}

// getDeployedVersion returns the currently deployed version of an app.
func getDeployedVersion(cl *dockerclient.Client, stackName string, recipeName string) (string, error) {
	log.Debugf("retrieve deployed version whether %s is already deployed", stackName)

	deployMeta, err := stack.IsDeployed(context.Background(), cl, stackName)
	if err != nil {
		return "", err
	}

	if !deployMeta.IsDeployed {
		return "", fmt.Errorf("%s is not deployed?", stackName)
	}

	if deployMeta.Version == "unknown" {
		return "", fmt.Errorf("failed to determine deployed version of %s", stackName)
	}

	return deployMeta.Version, nil
}

// getAvailableUpgrades returns all available versions of an app that are newer
// than the deployed version. It only includes major upgrades if the "--major"
// flag is set.
func getAvailableUpgrades(cl *dockerclient.Client, stackName string, recipeName string,
	deployedVersion string) ([]string, error) {
	catl, err := recipe.ReadRecipeCatalogue(internal.Offline)
	if err != nil {
		return nil, err
	}

	versions, err := recipe.GetRecipeCatalogueVersions(recipeName, catl)
	if err != nil {
		return nil, err
	}

	if len(versions) == 0 {
		log.Warnf("no published releases for %s in the recipe catalogue?", recipeName)
		return nil, nil
	}

	var availableUpgrades []string
	for _, version := range versions {
		parsedDeployedVersion, err := tagcmp.Parse(deployedVersion)
		if err != nil {
			return nil, err
		}

		parsedVersion, err := tagcmp.Parse(version)
		if err != nil {
			return nil, err
		}

		versionDelta, err := parsedDeployedVersion.UpgradeDelta(parsedVersion)
		if err != nil {
			return nil, err
		}

		if 0 < versionDelta.UpgradeType() && (versionDelta.UpgradeType() < 4 || includeMajorUpdates) {
			availableUpgrades = append(availableUpgrades, version)
		}
	}

	log.Debugf("available updates for %s: %s", stackName, availableUpgrades)

	return availableUpgrades, nil
}

// processRecipeRepoVersion clones, pulls, checks out the version and lints the
// recipe repository.
func processRecipeRepoVersion(r recipe.Recipe, version string) error {
	if err := r.EnsureExists(); err != nil {
		return err
	}

	if err := r.EnsureUpToDate(); err != nil {
		return err
	}

	if _, err := r.EnsureVersion(version); err != nil {
		return err
	}

	if err := lint.LintForErrors(r); err != nil {
		return err
	}

	return nil
}

// mergeAbraShEnv merges abra.sh env vars into the app env vars.
func mergeAbraShEnv(recipe recipe.Recipe, env envfile.AppEnv) error {
	abraShEnv, err := envfile.ReadAbraShEnvVars(recipe.AbraShPath)
	if err != nil {
		return err
	}

	for k, v := range abraShEnv {
		log.Debugf("read v:%s k: %s", v, k)
		env[k] = v
	}

	return nil
}

// createDeployConfig merges and enriches the compose config for the deployment.
func createDeployConfig(r recipe.Recipe, stackName string, env envfile.AppEnv) (*composetypes.Config, stack.Deploy, error) {
	env["STACK_NAME"] = stackName

	deployOpts := stack.Deploy{
		Namespace:    stackName,
		Prune:        false,
		ResolveImage: stack.ResolveImageAlways,
		Detach:       false,
	}

	composeFiles, err := r.GetComposeFiles(env)
	if err != nil {
		return nil, deployOpts, err
	}

	deployOpts.Composefiles = composeFiles
	compose, err := appPkg.GetAppComposeConfig(stackName, deployOpts, env)
	if err != nil {
		return nil, deployOpts, err
	}

	appPkg.ExposeAllEnv(stackName, compose, env)

	// after the upgrade the deployment won't be in chaos state anymore
	appPkg.SetChaosLabel(compose, stackName, false)
	appPkg.SetRecipeLabel(compose, stackName, r.Name)
	appPkg.SetUpdateLabel(compose, stackName, env)

	return compose, deployOpts, nil
}

// tryUpgrade performs the upgrade if all the requirements are fulfilled.
func tryUpgrade(cl *dockerclient.Client, stackName, recipeName string) error {
	if recipeName == "" {
		log.Debugf("don't update %s due to missing recipe name", stackName)
		return nil
	}

	chaos, err := getBoolLabel(cl, stackName, "chaos")
	if err != nil {
		return err
	}

	if chaos && !internal.Chaos {
		log.Debugf("don't update %s due to chaos deployment", stackName)
		return nil
	}

	updatesEnabled, err := getBoolLabel(cl, stackName, "autoupdate")
	if err != nil {
		return err
	}

	if !updatesEnabled {
		log.Debugf("don't update %s due to disabled auto updates or missing ENABLE_AUTO_UPDATE env", stackName)
		return nil
	}

	upgradeVersion, err := getLatestUpgrade(cl, stackName, recipeName)
	if err != nil {
		return err
	}

	if upgradeVersion == "" {
		log.Debugf("don't update %s due to no new version", stackName)
		return nil
	}

	err = upgrade(cl, stackName, recipeName, upgradeVersion)

	return err
}

// upgrade performs all necessary steps to upgrade an app.
func upgrade(cl *dockerclient.Client, stackName, recipeName, upgradeVersion string) error {
	env, err := getEnv(cl, stackName)
	if err != nil {
		return err
	}

	app := appPkg.App{
		Name:   stackName,
		Recipe: recipe.Get(recipeName),
		Server: SERVER,
		Env:    env,
	}

	r := recipe.Get(recipeName)

	if err = processRecipeRepoVersion(r, upgradeVersion); err != nil {
		return err
	}

	if err = mergeAbraShEnv(app.Recipe, app.Env); err != nil {
		return err
	}

	compose, deployOpts, err := createDeployConfig(r, stackName, app.Env)
	if err != nil {
		return err
	}

	log.Infof("upgrade %s (%s) to version %s", stackName, recipeName, upgradeVersion)

	err = stack.RunDeploy(cl, deployOpts, compose, stackName, true)

	return err
}

func newKadabraApp(version, commit string) *cobra.Command {
	rootCmd := &cobra.Command{
		Use:     "kadabra [cmd] [flags]",
		Version: fmt.Sprintf("%s-%s", version, commit[:7]),
		Short:   "The Co-op Cloud auto-updater 🤖 🚀",
		PersistentPreRun: func(cmd *cobra.Command, args []string) {
			log.Logger.SetStyles(charmLog.DefaultStyles())
			charmLog.SetDefault(log.Logger)

			if internal.Debug {
				log.SetLevel(log.DebugLevel)
				log.SetOutput(os.Stderr)
				log.SetReportCaller(true)
			}

			log.Debugf("kadabra version %s, commit %s", version, commit)
		},
	}

	rootCmd.PersistentFlags().BoolVarP(
		&internal.Debug, "debug", "d", false,
		"show debug messages",
	)

	rootCmd.PersistentFlags().BoolVarP(
		&internal.NoInput, "no-input", "n", false,
		"toggle non-interactive mode",
	)

	rootCmd.AddCommand(
		NotifyCommand,
		UpgradeCommand,
	)

	return rootCmd
}

// RunApp runs CLI abra app.
func RunApp(version, commit string) {
	app := newKadabraApp(version, commit)

	if err := app.Execute(); err != nil {
		log.Fatal(err)
	}
}

var (
	includeMajorUpdates bool
	updateAll           bool
)

func init() {
	NotifyCommand.Flags().BoolVarP(
		&includeMajorUpdates,
		"major",
		"m",
		false,
		"check for major updates",
	)

	UpgradeCommand.Flags().BoolVarP(
		&internal.Chaos,
		"chaos",
		"C",
		false,
		"ignore uncommitted recipes changes",
	)

	UpgradeCommand.Flags().BoolVarP(
		&includeMajorUpdates,
		"major",
		"m",
		false,
		"check for major updates",
	)

	UpgradeCommand.Flags().BoolVarP(
		&updateAll,
		"all",
		"a",
		false,
		"update all deployed apps",
	)
}