X-Git-Url: http://git.giacomolli.uk/onechat/blobdiff_plain/4b063ca25798c78cc03d1d07f67b02c94c95248d..f80b058ae0550a56b4e62f8e65c2a74349b970e4:/telegram.go?ds=inline

diff --git a/telegram.go b/telegram.go
index dabf2e8..9a24a4e 100644
--- a/telegram.go
+++ b/telegram.go
@@ -8,6 +8,7 @@ import (
 	"fmt"
 	"io"
 	"log"
+	"net/http"
 	"os"
 	"path/filepath"
 	"strings"
@@ -50,9 +51,10 @@ type botConfig struct {
 // telegramBot connects the private chat of the owner with the agent. It polls
 // the Bot API for new messages and sends each text message of the owner to the
 // agent. It ignores every other update. Its sender sends the replies, the
-// errors, and the user messages of the other clients to the chat as plain text,
-// and shows the typing action while a turn runs. Tool calls do not go to the
-// chat.
+// errors, the notices of the bot, and the user messages of the other clients to
+// the chat, and shows the typing action while a turn runs. Only the replies
+// have a format: their Markdown goes as message entities. The rest is plain
+// text. Tool calls do not go to the chat.
 //
 // The offset file holds the ID of the next update. It moves past an update
 // only after the message of the update is durable in the log, so a restart
@@ -74,6 +76,13 @@ type telegramBot struct {
 	ready chan struct{}
 }
 
+// botPart is the text of one message to the chat, at most messageUnits long,
+// and its entities.
+type botPart struct {
+	text     string
+	entities []botEntity
+}
+
 // offsetFile is the content of the offset file.
 type offsetFile struct {
 	Offset int64 `json:"offset"`
@@ -156,7 +165,7 @@ func newTelegramBot(api *botAPI, owner int64, offsetPath string, logger *log.Log
 // stop the agent.
 func (b *telegramBot) Notify(event Event) {
 	switch event.Kind {
-	case "busy", "idle", "reply", "error":
+	case "busy", "idle", "reply", "error", "notice":
 	case "user":
 		if event.Source == telegramSource {
 			return
@@ -228,7 +237,7 @@ func (b *telegramBot) send(ctx context.Context) {
 		case "idle":
 			busy = false
 		default:
-			for _, part := range splitMessage(botText(event), messageUnits) {
+			for _, part := range botParts(event) {
 				b.deliver(ctx, part)
 			}
 
@@ -260,16 +269,26 @@ func (b *telegramBot) typing(ctx context.Context) {
 	_ = b.api.SendTyping(ctx, b.owner)
 }
 
-// deliver sends text to the chat. It tries again after each failure that a
-// later try can fix, until ctx ends. It drops the text after any other failure.
-func (b *telegramBot) deliver(ctx context.Context, text string) {
+// deliver sends part to the chat. When Telegram refuses a part with entities
+// (HTTP 400), it sends the text of the part again once with no entities, so a
+// reply is not lost to a bad entity. It tries again after each failure that a
+// later try can fix, until ctx ends. It drops the part after any other failure.
+func (b *telegramBot) deliver(ctx context.Context, part botPart) {
 	wait := b.minWait
 	for {
-		err := b.api.SendMessage(ctx, b.owner, text)
+		err := b.api.SendMessage(ctx, b.owner, part.text, part.entities)
 		if err == nil || ctx.Err() != nil {
 			return
 		}
 
+		var answer *botError
+		if len(part.entities) > 0 && errors.As(err, &answer) && answer.Status == http.StatusBadRequest {
+			b.logger.Printf("entities refused, the message goes again as plain text: %v", err)
+			part.entities = nil
+
+			continue
+		}
+
 		retry, asked := retryable(err)
 		if !retry {
 			b.logger.Printf("message dropped: %v", err)
@@ -379,7 +398,7 @@ func (b *telegramBot) handle(ctx context.Context, l *loop, update botUpdate) err
 // notice queues a short answer of the bot for the chat.
 func (b *telegramBot) notice(text string) {
 	b.Notify(Event{
-		Kind: "reply",
+		Kind: "notice",
 		Text: text,
 	})
 }
@@ -422,6 +441,23 @@ func saveOffset(path string, offset int64) error {
 	return nil
 }
 
+// botParts returns the messages of event for the chat. The Markdown of a reply
+// becomes text with entities. Every other event is plain text. A reply that has
+// no text left after the conversion, such as an empty code block, goes as its
+// Markdown.
+func botParts(event Event) []botPart {
+	text, entities := botText(event), []botEntity(nil)
+	if event.Kind == "reply" {
+		text, entities = markdownEntities(event.Text)
+	}
+
+	if strings.TrimSpace(text) == "" {
+		text, entities = event.Text, nil
+	}
+
+	return splitEntities(text, entities, messageUnits)
+}
+
 // botText returns the text of event for the chat. A user message of another
 // client has its source as a mark.
 func botText(event Event) string {
@@ -435,6 +471,38 @@ func botText(event Event) string {
 	}
 }
 
+// splitEntities cuts text into parts with splitMessage, and gives each part the
+// entities in it, with offsets from the start of the part. An entity that
+// crosses a cut becomes one entity in each part.
+func splitEntities(text string, entities []botEntity, limit int) []botPart {
+	var parts []botPart
+	start := 0
+	for _, part := range splitMessage(text, limit) {
+		end := start + utf16Units(part)
+		var kept []botEntity
+		for _, entity := range entities {
+			from := max(entity.Offset, start)
+			to := min(entity.Offset+entity.Length, end)
+			if to <= from {
+				continue
+			}
+
+			entity.Offset = from - start
+			entity.Length = to - from
+			kept = append(kept, entity)
+		}
+
+		parts = append(parts, botPart{
+			text:     part,
+			entities: kept,
+		})
+
+		start = end
+	}
+
+	return parts
+}
+
 // splitMessage cuts text into parts of at most limit UTF-16 code units, the
 // unit of the Telegram message limit. It cuts after the last line break or
 // space of a part when one is in its second half, and else at the limit. It