// Copyright (C) 2023 Marius Schellenberger

package ssh

import (
	"context"
	"errors"
	"flag"
	"fmt"
	"os"
	"text/tabwriter"

	apiclient "git.giftfish.de/ston1th/keyctl/pkg/api/client"
	clientv1 "git.giftfish.de/ston1th/keyctl/pkg/api/v1/client"
	"git.giftfish.de/ston1th/keyctl/pkg/core"
	"golang.org/x/sys/unix"
)

var fs = flag.NewFlagSet("", flag.ExitOnError)

func exit(err error) {
	fmt.Fprintf(os.Stderr, "%s\n", err)
	os.Exit(1)
}

func Run(arg string) {
	ctx := context.Background()
	switch arg {
	case "approve":
		id, err := idFlags("access id")
		if err != nil {
			exit(err)
		}
		c := client()
		err = c.AcceptAccess(ctx, id)
		if err != nil {
			exit(err)
		}
	case "reject":
		id, err := idFlags("access id")
		if err != nil {
			exit(err)
		}
		c := client()
		err = c.RejectAccess(ctx, id)
		if err != nil {
			exit(err)
		}
	case "login":
		endpoint, err := loginFlags()
		if err != nil {
			exit(err)
		}
		opts, err := apiclient.ClientOptionsFromConfig(
			apiclient.Config{Endpoint: endpoint},
		)
		if err != nil {
			exit(err)
		}
		c := client(opts...)
		host, err := os.Hostname()
		if err != nil {
			exit(err)
		}
		// TODO: fix me (user)
		ok, err := c.Access(ctx, host, "user")
		if err != nil {
			exit(err)
		}
		if ok {
			unix.Exec("/bin/bash", []string{"bash"}, os.Environ()) // does not return
		}
	case "req":
		c := client()
		access, err := c.GetAccess(ctx)
		if err != nil {
			exit(err)
		}
		print(access)
	}
	os.Exit(0)
}

func client(opts ...apiclient.ClientOption) (c *clientv1.Client) {
	var err error
	if opts == nil {
		opts, err = apiclient.ClientOptionsFromEnv()
		if err != nil {
			exit(err)
		}
	}
	apic := apiclient.NewClient(opts...)
	//if socket, ok := apic.IsUnix(); ok {
	//	err = unveil(socket)
	//	if err != nil {
	//		exit(err)
	//	}
	//}
	c, err = clientv1.NewClient(apic)
	if err != nil {
		exit(err)
	}
	return
}

func print(tw core.TableWriter) {
	if tw.Len() == 0 {
		return
	}
	w := tabwriter.NewWriter(os.Stdout, 1, 0, 1, ' ', tabwriter.Debug)
	fmt.Fprintln(w, tw.Fields())
	for _, v := range tw.Values() {
		fmt.Fprintln(w, v)
	}
	w.Flush()
}

func idFlags(desc string) (id string, err error) {
	fs.StringVar(&id, "id", "", desc)
	fs.Parse(os.Args[3:])
	if id == "" {
		err = errors.New("missing flag: id")
	}
	return
}

func loginFlags() (endpoint string, err error) {
	fs.StringVar(&endpoint, "endpoint", "", "keyctl endpoint")
	fs.Parse(os.Args[3:])
	if endpoint == "" {
		err = errors.New("missing flag: endpoint")
	}
	return
}