package keys

import (
	"context"
	"encoding/json"
	"fmt"
	"os"
	"strings"

	"github.com/urfave/cli/v3"
	"tangled.org/core/knot2/config"
	"tangled.org/core/knot2/db"
	"tangled.org/core/log"
)

func Command() *cli.Command {
	return &cli.Command{
		Name:   "keys",
		Usage:  "fetch public keys from the knot server",
		Action: Run,
		Flags: []cli.Flag{
			&cli.StringFlag{
				Name:     "config",
				Aliases:  []string{"c"},
				Usage:    "config path",
				Required: true,
			},
			&cli.StringFlag{
				Name:    "output",
				Aliases: []string{"o"},
				Usage:   "output format (table, json, authorized-keys)",
				Value:   "table",
			},
		},
	}
}

func Run(ctx context.Context, cmd *cli.Command) error {
	l := log.FromContext(ctx)
	l = log.SubLogger(l, cmd.Name)
	ctx = log.IntoContext(ctx, l)

	var (
		output     = cmd.String("output")
		configPath = cmd.String("config")
	)

	cfg, err := config.Load(ctx, configPath)
	if err != nil {
		return fmt.Errorf("failed to load config: %w", err)
	}

	d, err := db.New(cfg.DbPath())
	if err != nil {
		return fmt.Errorf("failed to load db: %w", err)
	}

	pubkeyDidListMap, err := db.GetPubkeyDidListMap(d)
	if err != nil {
		return err
	}

	switch output {
	case "json":
		prettyJSON, err := json.MarshalIndent(pubkeyDidListMap, "", "    ")
		if err != nil {
			return err
		}
		if _, err := os.Stdout.Write(prettyJSON); err != nil {
			return err
		}
	case "table":
		fmt.Printf("%-40s %-40s\n", "KEY", "DID")
		fmt.Println(strings.Repeat("-", 80))

		for key, didList := range pubkeyDidListMap {
			fmt.Printf("%-40s %-40s\n", key, strings.Join(didList, ","))
		}
	case "authorized-keys":
		for key, didList := range pubkeyDidListMap {
			executablePath, err := os.Executable()
			if err != nil {
				l.Error("error getting path of executable", "error", err)
				return err
			}
			command := fmt.Sprintf("%s guard", executablePath)
			for _, did := range didList {
				command += fmt.Sprintf(" -user %s", did)
			}
			fmt.Printf(
				`command="%s",no-port-forwarding,no-X11-forwarding,no-agent-forwarding,no-pty %s`+"\n",
				command,
				key,
			)
		}
		if err != nil {
			l.Error("error writing to stdout", "error", err)
			return err
		}
	}

	return nil
}