package server

import (
	"os"
	"path/filepath"

	"coopcloud.tech/abra/cli/internal"
	"coopcloud.tech/abra/pkg/autocomplete"
	"coopcloud.tech/abra/pkg/client"
	"coopcloud.tech/abra/pkg/config"
	contextPkg "coopcloud.tech/abra/pkg/context"
	"coopcloud.tech/abra/pkg/dns"
	"coopcloud.tech/abra/pkg/log"
	"coopcloud.tech/abra/pkg/server"
	sshPkg "coopcloud.tech/abra/pkg/ssh"
	"github.com/spf13/cobra"
)

var ServerAddCommand = &cobra.Command{
	Use:     "add [[server] | --local] [flags]",
	Aliases: []string{"a"},
	Short:   "Add a new server",
	Long: `Add a new server to your configuration so that it can be managed by Abra.

Abra relies on the standard SSH command-line and ~/.ssh/config for client
connection details. You must configure an entry per-host in your ~/.ssh/config
for each server:

  Host 1312.net 1312
    Hostname 1312.net
    User antifa
    Port 12345
    IdentityFile ~/.ssh/antifa@somewhere

If "--local" is passed, then Abra assumes that the current local server is
intended as the target server. This is useful when you want to have your entire
Co-op Cloud config located on the server itself, and not on your local
developer machine. The domain is then set to "default".`,
	Example: "  abra server add 1312.net",
	Args:    cobra.RangeArgs(0, 1),
	ValidArgsFunction: func(
		cmd *cobra.Command,
		args []string,
		toComplete string) ([]string, cobra.ShellCompDirective) {
		if !local {
			return autocomplete.ServerNameComplete()
		}
		return nil, cobra.ShellCompDirectiveDefault
	},
	Run: func(cmd *cobra.Command, args []string) {
		if len(args) > 0 && local {
			log.Fatal("cannot use [server] and --local together")
		}

		if len(args) == 0 && !local {
			log.Fatal("missing argument or --local/-l flag")
		}

		name := "default"
		if !local {
			name = internal.ValidateDomain(args)
		}

		// NOTE(d1): reasonable 5 second timeout for connections which can't
		// succeed. The connection is attempted twice, so this results in 10
		// seconds.
		timeout := client.WithTimeout(5)

		if local {
			created, err := createServerDir(name)
			if err != nil {
				log.Fatal(err)
			}

			log.Debugf("attempting to create client for %s", name)

			if _, err := client.New(name, timeout); err != nil {
				cleanUp(name)
				log.Fatal(err)
			}

			if created {
				log.Info("local server successfully added")
			} else {
				log.Warn("local server already exists")
			}

			return
		}

		_, err := createServerDir(name)
		if err != nil {
			log.Fatal(err)
		}

		created, err := newContext(name)
		if err != nil {
			cleanUp(name)
			log.Fatalf("unable to create local context: %s", err)
		}

		log.Debugf("attempting to create client for %s", name)

		if _, err := client.New(name, timeout); err != nil {
			cleanUp(name)
			log.Fatalf("ssh %s error: %s", name, sshPkg.Fatal(name, err))
		}

		if created {
			log.Infof("%s successfully added", name)

			if _, err := dns.EnsureIPv4(name); err != nil {
				log.Warnf("unable to resolve IPv4 for %s", name)
			}

			return
		}

		log.Warnf("%s already exists", name)
	},
}

// cleanUp cleans up the partially created context/client details for a failed
// "server add" attempt.
func cleanUp(name string) {
	if name != "default" {
		log.Debugf("serverAdd: cleanUp: cleaning up context for %s", name)
		if err := client.DeleteContext(name); err != nil {
			log.Fatal(err)
		}
	}

	serverDir := filepath.Join(config.SERVERS_DIR, name)
	files, err := config.GetAllFilesInDirectory(serverDir)
	if err != nil {
		log.Fatalf("serverAdd: cleanUp: unable to list files in %s: %s", serverDir, err)
	}

	if len(files) > 0 {
		log.Debugf("serverAdd: cleanUp: %s is not empty, aborting cleanup", serverDir)
		return
	}

	if err := os.RemoveAll(serverDir); err != nil {
		log.Fatalf("serverAdd: cleanUp: failed to remove %s: %s", serverDir, err)
	}
}

// newContext creates a new internal Docker context for a server. This is how
// Docker manages SSH connection details. These are stored to disk in
// ~/.docker. Abra can manage this completely for the user, so it's an
// implementation detail.
func newContext(name string) (bool, error) {
	store := contextPkg.NewDefaultDockerContextStore()
	contexts, err := store.Store.List()
	if err != nil {
		return false, err
	}

	for _, context := range contexts {
		if context.Name == name {
			log.Debugf("context for %s already exists", name)
			return false, nil
		}
	}

	log.Debugf("creating context with domain %s", name)

	if err := client.CreateContext(name); err != nil {
		return false, nil
	}

	return true, nil
}

// createServerDir creates the ~/.abra/servers/... directory for a new server.
func createServerDir(name string) (bool, error) {
	if err := server.CreateServerDir(name); err != nil {
		if !os.IsExist(err) {
			return false, err
		}

		log.Debugf("server dir for %s already created", name)

		return false, nil
	}

	return true, nil
}

var (
	local bool
)

func init() {
	ServerAddCommand.Flags().BoolVarP(
		&local,
		"local",
		"l",
		false,
		"use local server",
	)
}