package ui

import (
	"bufio"
	"fmt"
	"os"
	"strings"
	"syscall"

	"golang.org/x/term"
)

// GetUserInputForGhcr prompts the user for GitHub-related credentials for GHCR.
func GetUserInputForGhcr() (username, registryToken, orgToken string, err error) {
	reader := bufio.NewReader(os.Stdin)

	fmt.Print("Enter your GitHub username: ")
	username, err = reader.ReadString('\n')
	if err != nil {
		return
	}
	username = strings.TrimSpace(username)
	if username == "" {
		err = fmt.Errorf("username cannot be empty")
		return
	}

	registryToken, err = promptForToken(reader, "Enter your GitHub PAT for container registry")
	if err != nil {
		return
	}

	orgToken, err = promptForToken(reader, "Enter your GitHub PAT for organization management")
	if err != nil {
		return
	}

	return
}

// GetUserInputForDockerHub prompts the user for Docker Hub credentials.
func GetUserInputForDockerHub() (username, password string, err error) {
	reader := bufio.NewReader(os.Stdin)
	fmt.Print("Enter your Docker Hub username: ")
	username, err = reader.ReadString('\n')
	if err != nil {
		return
	}
	username = strings.TrimSpace(username)

	fmt.Print("Enter your Docker Hub password or access token: ")
	passwordBytes, err := term.ReadPassword(int(syscall.Stdin))
	fmt.Println()
	if err != nil {
		return "", "", err
	}
	password = string(passwordBytes)

	if username == "" || password == "" {
		err = fmt.Errorf("username and password cannot be empty")
	}
	return
}

// GetUserInputForGithubAuth prompts the user for a general GitHub PAT.
func GetUserInputForGithubAuth() (username, token string, err error) {
	reader := bufio.NewReader(os.Stdin)

	fmt.Print("Enter your GitHub username: ")
	username, err = reader.ReadString('\n')
	if err != nil {
		return
	}
	username = strings.TrimSpace(username)
	if username == "" {
		err = fmt.Errorf("username cannot be empty")
		return
	}

	token, err = promptForToken(reader, "Enter your GitHub PAT for repository access")
	if err != nil {
		return
	}

	return
}

func promptForToken(reader *bufio.Reader, prompt string) (string, error) {
	token := promptSecret(reader, prompt, "")
	if token == "" {
		return "", fmt.Errorf("token cannot be empty")
	}

	validPrefixes := []string{"ghp_", "gho_", "ghu_", "ghs_", "ghr_", "github_pat_"}
	hasValidPrefix := false
	for _, prefix := range validPrefixes {
		if strings.HasPrefix(token, prefix) {
			hasValidPrefix = true
			break
		}
	}

	if !hasValidPrefix {
		fmt.Printf("[WARNING] The token does not appear to be a valid GitHub PAT (should start with one of %v)\n", validPrefixes)
		fmt.Print("Do you want to continue anyway? (y/N): ")
		confirm, _ := reader.ReadString('\n')
		if strings.TrimSpace(strings.ToLower(confirm)) != "y" {
			return "", fmt.Errorf("operation cancelled by user")
		}
	}

	return token, nil
}

func promptSecret(reader *bufio.Reader, prompt, fallback string) string {
	if fallback != "" {
		fmt.Printf("%s [saved]: ", prompt)
	} else {
		fmt.Printf("%s: ", prompt)
	}
	secretBytes, err := term.ReadPassword(int(syscall.Stdin))
	fmt.Println()
	if err != nil {
		return fallback
	}
	secret := strings.TrimSpace(string(secretBytes))
	if secret == "" {
		return fallback
	}
	return secret
}