package main

import (
	"fmt"
	"net"
	"os"
	"strings"

	glider_ssh "github.com/gliderlabs/ssh"
	"go.lindenii.runxiyu.org/lindenii-common/ansiec"
	"go.lindenii.runxiyu.org/lindenii-common/clog"
	go_ssh "golang.org/x/crypto/ssh"
)

var (
	server_public_key_string      string
	server_public_key_fingerprint string
	server_public_key             go_ssh.PublicKey
)

func serve_ssh(listener net.Listener) error {
	host_key_bytes, err := os.ReadFile(config.SSH.Key)
	if err != nil {
		return err
	}

	host_key, err := go_ssh.ParsePrivateKey(host_key_bytes)
	if err != nil {
		return err
	}

	server_public_key = host_key.PublicKey()
	server_public_key_string = string(go_ssh.MarshalAuthorizedKey(server_public_key))
	server_public_key_fingerprint = string(go_ssh.FingerprintSHA256(server_public_key))

	server := &glider_ssh.Server{
		Handler: func(session glider_ssh.Session) {
			client_public_key := session.PublicKey()
			var client_public_key_string string
			if client_public_key != nil {
				client_public_key_string = strings.TrimSuffix(string(go_ssh.MarshalAuthorizedKey(client_public_key)), "\n")
			}

			clog.Info("Incoming SSH: " + session.RemoteAddr().String() + " " + client_public_key_string + " " + session.RawCommand())

			fmt.Fprintln(session.Stderr(), ansiec.Blue + "Lindenii Forge "+VERSION+", source at "+strings.TrimSuffix(config.HTTP.Root, "/")+"/:/source/" + ansiec.Reset + "\r")

			fmt.Fprintln(session.Stderr(), ansiec.Blue+"Lindenii Forge "+VERSION+", source at "+strings.TrimSuffix(config.HTTP.Root, "/")+"/:/source/"+ansiec.Reset+"\r")

			cmd := session.Command()

			if len(cmd) < 2 {
				fmt.Fprintln(session.Stderr(), "Insufficient arguments\r")
				return
			}

			switch cmd[0] {
			case "git-upload-pack":
				if len(cmd) > 2 {
					fmt.Fprintln(session.Stderr(), "Too many arguments\r")
					return
				}
				err = ssh_handle_upload_pack(session, client_public_key_string, cmd[1])
			case "git-receive-pack":
				if len(cmd) > 2 {
					fmt.Fprintln(session.Stderr(), "Too many arguments\r")
					return
				}
				err = ssh_handle_receive_pack(session, client_public_key_string, cmd[1])
			default:
				fmt.Fprintln(session.Stderr(), "Unsupported command: "+cmd[0]+"\r")
				return
			}
			if err != nil {
				fmt.Fprintln(session.Stderr(), err.Error())
				return
			}
		},
		PublicKeyHandler:           func(ctx glider_ssh.Context, key glider_ssh.PublicKey) bool { return true },
		KeyboardInteractiveHandler: func(ctx glider_ssh.Context, challenge go_ssh.KeyboardInteractiveChallenge) bool { return true },
		// It is intentional that we do not check any credentials and accept all connections.
		// This allows all users to connect and clone repositories. However, the public key
		// is passed to handlers, so e.g. the push handler could check the key and reject the
		// push if it needs to.
	}

	server.AddHostKey(host_key)

	err = server.Serve(listener)
	if err != nil {
		clog.Fatal(1, "Serving SSH: "+err.Error())
	}

	return nil
}

package main

import (
	"context"
	"errors"
	"fmt"
	"io"
	"net/url"
	"strings"

	"go.lindenii.runxiyu.org/lindenii-common/ansiec"
)

var err_ssh_illegal_endpoint = errors.New("illegal endpoint during SSH access")

func get_repo_path_perms_from_ssh_path_pubkey(ctx context.Context, ssh_path string, ssh_pubkey string) (group_name string, repo_name string, repo_id int, repo_path string, direct_access bool, contrib_requirements string, user_type string, user_id int, err error) {
	segments := strings.Split(strings.TrimPrefix(ssh_path, "/"), "/")

	for i, segment := range segments {
		var err error
		segments[i], err = url.PathUnescape(segment)
		if err != nil {
			return "", "", 0, "", false, "", "", 0, err
		}
	}

	if segments[0] == ":" {
		return "", "", 0, "", false, "", "", 0, err_ssh_illegal_endpoint
	}

	separator_index := -1
	for i, part := range segments {
		if part == ":" {
			separator_index = i
			break
		}
	}
	if segments[len(segments)-1] == "" {
		segments = segments[:len(segments)-1]
	}

	switch {
	case separator_index == -1:
		return "", "", 0, "", false, "", "", 0, err_ssh_illegal_endpoint
	case len(segments) <= separator_index+2:
		return "", "", 0, "", false, "", "", 0, err_ssh_illegal_endpoint
	}

	group_name = segments[0]
	module_type := segments[separator_index+1]
	module_name := segments[separator_index+2]
	repo_name = module_name
	switch module_type {
	case "repos":
		_1, _2, _3, _4, _5, _6, _7 := get_path_perm_by_group_repo_key(ctx, group_name, module_name, ssh_pubkey)
		return group_name, repo_name, _1, _2, _3, _4, _5, _6, _7
	default:
		return "", "", 0, "", false, "", "", 0, err_ssh_illegal_endpoint
	}
}

func wf_error(w io.Writer, format string, args ...any) {

	fmt.Fprintln(w, ansiec.Red + fmt.Sprintf(format, args...) + ansiec.Reset)

	fmt.Fprintln(w, ansiec.Red+fmt.Sprintf(format, args...)+ansiec.Reset)

}