package sshx

import (
	"context"
	"errors"
	"fmt"
	"os"

	"github.com/barerepo/server/internal/gitx"
	"github.com/barerepo/server/internal/hook"
	"github.com/barerepo/server/internal/transport"
)

// Serve decides whether this named account may do this, then hands git the connection.
func Serve(ctx context.Context, t *transport.Server, account, cmd string) error {
	r, err := Parse(cmd)
	if err != nil {
		return err
	}
	intent := transport.Read
	if r.Write() {
		// ssh runs one receive-pack per push, so there is no advertise to hold creation back from.
		intent = transport.Write
	}
	res, err := t.Open(ctx, r.Owner, r.Name, account, intent)
	var moved transport.Redirect
	switch {
	case errors.As(err, &moved):
		// ssh has no redirect, so say where it went and what to run about it.
		user := t.Cfg.Server.SSHUser
		if user == "" {
			user = "git"
		}
		return fmt.Errorf("%s/%s moved to %s/%s. update your remote:\n"+
			"       git remote set-url origin %s@%s:%s/%s",
			r.Owner, r.Name, moved.Owner, moved.Name,
			user, t.Cfg.Server.SSHHost, moved.Owner, moved.Name)
	case err != nil:
		return err
	}
	if res.Warning != "" {
		fmt.Fprintln(os.Stderr, res.Warning)
	}

	env := hook.Env{
		Account: account, Owner: res.Owner, Name: res.Name, Dir: res.Dir,
		Created: res.Created,
		URL:     t.Cfg.Server.ExternalURL + "/" + res.Owner + "/" + res.Name,
		Config:  t.Cfg.Path,
	}
	verb := r.Verb[len("git-"):]
	return gitx.Pipe(ctx, res.Dir, os.Stdin, os.Stdout, os.Stderr, env.Vars(), verb, ".")
}