From afb63d6437a6955124e5339ec9ff2d14ce7f575e Mon Sep 17 00:00:00 2001
From: Aleksandr Razumov <ernado@go-faster.org>
Date: Fri, 29 Nov 2024 10:20:49 +0300
Subject: [PATCH] feat(telegram): add OnSelfError

Ref: #1458
---
 telegram/client.go  | 4 ++++
 telegram/connect.go | 6 ++++++
 telegram/options.go | 8 ++++++++
 3 files changed, 18 insertions(+)

diff --git a/telegram/client.go b/telegram/client.go
index 32ffa4eaf1..bd39d5acd1 100644
--- a/telegram/client.go
+++ b/telegram/client.go
@@ -134,6 +134,9 @@ type Client struct {
 
 	// onTransfer is called in transfer.
 	onTransfer AuthTransferHandler
+
+	// onSelfError is called on error calling Self().
+	onSelfError func(ctx context.Context, err error) error
 }
 
 // NewClient creates new unstarted client.
@@ -169,6 +172,7 @@ func NewClient(appID int, appHash string, opt Options) *Client {
 		noUpdatesMode:    opt.NoUpdates,
 		mw:               opt.Middlewares,
 		onTransfer:       opt.OnTransfer,
+		onSelfError:      opt.OnSelfError,
 	}
 	if opt.TracerProvider != nil {
 		client.tracer = opt.TracerProvider.Tracer(oteltg.Name)
diff --git a/telegram/connect.go b/telegram/connect.go
index 3b359dbc3d..92ec227cef 100644
--- a/telegram/connect.go
+++ b/telegram/connect.go
@@ -30,6 +30,12 @@ func (c *Client) runUntilRestart(ctx context.Context) error {
 				if !auth.IsUnauthorized(err) {
 					c.log.Warn("Got error on self", zap.Error(err))
 				}
+				if h := c.onSelfError; h != nil {
+					// Help with https://github.com/gotd/td/issues/1458.
+					if err := h(ctx, err); err != nil {
+						return errors.Wrap(err, "onSelfError")
+					}
+				}
 				return nil
 			}
 
diff --git a/telegram/options.go b/telegram/options.go
index 9c271fd149..a35e3f85d3 100644
--- a/telegram/options.go
+++ b/telegram/options.go
@@ -100,6 +100,14 @@ type Options struct {
 	// OnTransfer is called during authorization transfer.
 	// See [AuthTransferHandler] for details.
 	OnTransfer AuthTransferHandler
+
+	// OnSelfError is called when client receives error calling Self() on connect.
+	// Return error to stop reconnection.
+	//
+	// NB: this method is called immediately after connection, so it's not expected to be
+	// non-nil error on first connection before auth, so it's safe to return nil until
+	// first successful auth.
+	OnSelfError func(ctx context.Context, err error) error
 }
 
 func (opt *Options) setDefaults() {