package auth

import (
	"fmt"
	"net/url"
)

func NewFromURL(authURL string) (AuthProvider, error) {
	u, err := url.Parse(authURL)
	if err != nil {
		return nil, fmt.Errorf("error parsing auth URL: %s", err.Error())
	}

	switch u.Scheme {
	case "imap":
		return NewIMAP(u.Host, false), nil
	case "imaps":
		return NewIMAP(u.Host, true), nil
	case "pam":
		return NewPAM()
	case "file":
		path := u.Path
		if u.Host != "" {
			path = u.Host + path
		}
		return NewHtpasswd(path)
	case "null":
		return NewNull()
	case "http", "https":
		if u.User == nil {
			return nil, fmt.Errorf("missing client ID for OAuth 2.0")
		}
		clientID := u.User.Username()
		clientSecret, _ := u.User.Password()
		u.User = nil
		return NewOAuth2(u.String(), clientID, clientSecret)
	default:
		return nil, fmt.Errorf("no auth provider found for %s:// URL", u.Scheme)
	}
}