package commands

import (
	"fmt"
	"os"

	"golang.org/x/crypto/ssh"
)

func ResolvePort(host string) string {

	if len(host) > 0 {
		hasPort := false
		for i := len(host) - 1; i >= 0; i-- {
			if host[i] == ':' {
				hasPort = true
				break
			}
			if host[i] == ']' {
				break
			}
		}
		if !hasPort {
			host = host + ":22"
		}
	}

	return host

}

func GetSigner(private_key_file string) (ssh.Signer, error) {

	key_bytes, err := os.ReadFile(private_key_file)
	if err != nil {
		return nil, fmt.Errorf("error reading private key from file %s: %w", private_key_file, err)
	}

	signer, err := ssh.ParsePrivateKey(key_bytes)
	if err != nil {
		return nil, fmt.Errorf("error parsing private key: %w", err)
	}

	return signer, nil

}

func GetClient(private_key_file, username, host string) (*ssh.Client, error) {

	signer, err := GetSigner(private_key_file)
	if err != nil {
		return nil, err
	}

	config := &ssh.ClientConfig{
		User: username,
		Auth: []ssh.AuthMethod{
			ssh.PublicKeys(signer),
		},
		HostKeyCallback: ssh.InsecureIgnoreHostKey(),
	}

	addr := ResolvePort(host)

	client, err := ssh.Dial("tcp", addr, config)
	if err != nil {
		return nil, fmt.Errorf("error connecting to server: %w", err)
	}

	return client, nil
}