--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/vendor/github.com/McKael/madon/v3/login.go	Sat Feb 04 12:58:35 2023 +0100
@@ -0,0 +1,129 @@
+/*
+Copyright 2017-2018 Mikael Berthe
+
+Licensed under the MIT license.  Please see the LICENSE file is this directory.
+*/
+
+package madon
+
+import (
+	"encoding/json"
+	"strings"
+
+	"golang.org/x/net/context"
+	"golang.org/x/oauth2"
+
+	"github.com/pkg/errors"
+	"github.com/sendgrid/rest"
+)
+
+const oAuthRelPath = "/oauth/"
+
+// UserToken represents a user token as returned by the Mastodon API
+type UserToken struct {
+	AccessToken string `json:"access_token"`
+	CreatedAt   int64  `json:"created_at"`
+	Scope       string `json:"scope"`
+	TokenType   string `json:"token_type"`
+}
+
+// LoginBasic does basic user authentication
+func (mc *Client) LoginBasic(username, password string, scopes []string) error {
+	if mc == nil {
+		return ErrUninitializedClient
+	}
+
+	if username == "" {
+		return errors.New("missing username")
+	}
+	if password == "" {
+		return errors.New("missing password")
+	}
+
+	hdrs := make(map[string]string)
+	opts := make(map[string]string)
+
+	hdrs["User-Agent"] = "madon/" + MadonVersion
+
+	opts["grant_type"] = "password"
+	opts["client_id"] = mc.ID
+	opts["client_secret"] = mc.Secret
+	opts["username"] = username
+	opts["password"] = password
+	if len(scopes) > 0 {
+		opts["scope"] = strings.Join(scopes, " ")
+	}
+
+	req := rest.Request{
+		BaseURL:     mc.InstanceURL + oAuthRelPath + "token",
+		Headers:     hdrs,
+		QueryParams: opts,
+		Method:      rest.Post,
+	}
+
+	r, err := restAPI(req)
+	if err != nil {
+		return err
+	}
+
+	var resp UserToken
+
+	err = json.Unmarshal([]byte(r.Body), &resp)
+	if err != nil {
+		return errors.Wrap(err, "cannot unmarshal server response")
+	}
+
+	mc.UserToken = &resp
+	return nil
+}
+
+// SetUserToken sets an existing user credentials
+// No verification of the arguments is made.
+func (mc *Client) SetUserToken(token, username, password string, scopes []string) error {
+	if mc == nil {
+		return ErrUninitializedClient
+	}
+
+	mc.UserToken = &UserToken{
+		AccessToken: token,
+		Scope:       strings.Join(scopes, " "),
+		TokenType:   "bearer",
+	}
+	return nil
+}
+
+// LoginOAuth2 handles OAuth2 authentication
+// If code is empty, the URL to the server consent page will be returned;
+// if not, the user token is set.
+func (mc *Client) LoginOAuth2(code string, scopes []string) (string, error) {
+	if mc == nil {
+		return "", ErrUninitializedClient
+	}
+
+	conf := &oauth2.Config{
+		ClientID:     mc.ID,
+		ClientSecret: mc.Secret,
+		Scopes:       scopes,
+		Endpoint: oauth2.Endpoint{
+			AuthURL:  mc.InstanceURL + oAuthRelPath + "authorize",
+			TokenURL: mc.InstanceURL + oAuthRelPath + "token",
+		},
+		RedirectURL: NoRedirect,
+	}
+
+	if code == "" {
+		// URL to consent page to ask for permission
+		// for the scopes specified above.
+		return conf.AuthCodeURL("state", oauth2.AccessTypeOffline), nil
+	}
+
+	// Return token
+	t, err := conf.Exchange(context.TODO(), code)
+	if err != nil {
+		return "", errors.Wrap(err, "cannot convert code into a token")
+	}
+	if t == nil || t.AccessToken == "" {
+		return "", errors.New("empty token")
+	}
+	return "", mc.SetUserToken(t.AccessToken, "", "", scopes)
+}