)
const (
- // telegramAPI is the Telegram Bot API service.
- telegramAPI = "https://api.telegram.org"
+ // telegramAPIURL is the Telegram Bot API service.
+ telegramAPIURL = "https://api.telegram.org"
- // botConfigFileName is the bot config in the data directory. The daemon
- // runs the bot only when the file exists.
- botConfigFileName = "telegram.json"
+ // telegramConfigFileName is the bot config in the data directory. The
+ // daemon runs the bot only when the file exists.
+ telegramConfigFileName = "telegram.json"
- // offsetFileName is the update offset of the bot in the agent directory.
- offsetFileName = "telegram-offset.json"
+ // telegramOffsetFileName is the update offset of the bot in the agent
+ // directory.
+ telegramOffsetFileName = "telegram-offset.json"
// telegramSource is the source of the user messages from Telegram.
telegramSource = "telegram"
- // messageUnits is the most UTF-16 code units of one Telegram message.
- messageUnits = 4096
+ // telegramMessageUnits is the most UTF-16 code units of one Telegram
+ // message.
+ telegramMessageUnits = 4096
- // richMessageBytes is the most bytes of the Markdown of one rich
+ // telegramRichBytes is the most bytes of the Markdown of one rich
// message. The Bot API allows 32768 characters of rendered text, and
// the Markdown of a text has at least as many bytes as the text has
// characters.
- richMessageBytes = 32768
+ telegramRichBytes = 32768
- // typingInterval is how often the bot shows the typing action while a
- // turn runs. Telegram shows the action for about five seconds.
- typingInterval = 4 * time.Second
+ // telegramTypingInterval is how often the bot shows the typing action
+ // while a turn runs. Telegram shows the action for about five seconds.
+ telegramTypingInterval = 4 * time.Second
- // textOnly is the answer to a message that is not text.
- textOnly = "Only text messages are supported."
+ // telegramTextOnly is the answer to a message that is not text.
+ telegramTextOnly = "Only text messages are supported."
)
-// botConfig holds the settings of telegram.json: the bot token and the user ID
-// of the owner. The token is a secret, so the file must have mode 0600.
-type botConfig struct {
- Token string `json:"token"`
- Owner int64 `json:"owner"`
-}
-
-// 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, 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
-// does not lose a message. A crash between the flush and the offset write
-// makes Telegram send the update again, and the message repeats once.
-//
-// A failed Bot API call waits and tries again, from minWait up to maxWait, or
-// as long as the Bot API asks. It never stops the agent.
-type telegramBot struct {
- api *botAPI
- owner int64
- offsetPath string
- logger *log.Logger
- minWait time.Duration
- maxWait time.Duration
-
- mutex sync.Mutex
- queue []Event
- 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"`
-}
-
-// loadBotConfig reads telegram.json in dir. It returns false when the file
+// loadTelegramConfig reads telegram.json in dir. It returns false when the file
// does not exist. An error never holds the token.
-func loadBotConfig(dir string) (botConfig, bool, error) {
- path := filepath.Join(dir, botConfigFileName)
+func loadTelegramConfig(dir string) (TelegramConfig, bool, error) {
+ path := filepath.Join(dir, telegramConfigFileName)
info, err := os.Stat(path)
if errors.Is(err, os.ErrNotExist) {
- return botConfig{}, false, nil
+ return TelegramConfig{}, false, nil
}
if err != nil {
- return botConfig{}, false, fmt.Errorf("read bot config: %w", err)
+ return TelegramConfig{}, false, fmt.Errorf("read bot config: %w", err)
}
if info.Mode().Perm()&0o077 != 0 {
- return botConfig{}, false, fmt.Errorf("%s holds the bot token, so its mode must be 0600", botConfigFileName)
+ return TelegramConfig{}, false, fmt.Errorf("%s holds the bot token, so its mode must be 0600", telegramConfigFileName)
}
data, err := os.ReadFile(path)
if err != nil {
- return botConfig{}, false, fmt.Errorf("read bot config: %w", err)
+ return TelegramConfig{}, false, fmt.Errorf("read bot config: %w", err)
}
- var config botConfig
+ var config TelegramConfig
decoder := json.NewDecoder(bytes.NewReader(data))
decoder.DisallowUnknownFields()
err = decoder.Decode(&config)
}
if err != nil {
- return botConfig{}, false, fmt.Errorf("%s is not valid JSON with the fields token and owner", botConfigFileName)
+ return TelegramConfig{}, false, fmt.Errorf("%s is not valid JSON with the fields token and owner", telegramConfigFileName)
}
err = config.validate()
if err != nil {
- return botConfig{}, false, fmt.Errorf("%s: %w", botConfigFileName, err)
+ return TelegramConfig{}, false, fmt.Errorf("%s: %w", telegramConfigFileName, err)
}
return config, true, nil
}
+// newTelegramBot returns the bot of owner on api. The offset file is at
+// offsetPath, and logger gets the failures. No log line holds the text of a
+// message.
+func newTelegramBot(api *TelegramAPI, owner int64, offsetPath string, logger *log.Logger) *TelegramBot {
+ return &TelegramBot{
+ api: api,
+ owner: owner,
+ offsetPath: offsetPath,
+ logger: logger,
+ minWait: time.Second,
+ maxWait: time.Minute,
+ ready: make(chan struct{}, 1),
+ }
+}
+
+// TelegramConfig holds the settings of telegram.json: the bot token and the
+// user ID of the owner. The token is a secret, so the file must have mode 0600.
+type TelegramConfig struct {
+ Token string `json:"token"`
+ Owner int64 `json:"owner"`
+}
+
// validate makes sure that the token has the form of a bot token and that the
// owner is a user ID. The token goes into a URL path, so it can only hold the
// characters of a bot token.
-func (c botConfig) validate() error {
+func (c TelegramConfig) validate() error {
id, secret, found := strings.Cut(c.Token, ":")
if !found || id == "" || secret == "" || strings.Trim(id, "0123456789") != "" || strings.Trim(secret, "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ_-") != "" {
return errors.New("token does not have the form of a bot token from BotFather")
return nil
}
-// newTelegramBot returns the bot of owner on api. The offset file is at
-// offsetPath, and logger gets the failures. No log line holds the text of a
-// message.
-func newTelegramBot(api *botAPI, owner int64, offsetPath string, logger *log.Logger) *telegramBot {
- return &telegramBot{
- api: api,
- owner: owner,
- offsetPath: offsetPath,
- logger: logger,
- minWait: time.Second,
- maxWait: time.Minute,
- ready: make(chan struct{}, 1),
- }
+// 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, 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 rich messages, which Telegram renders
+// itself, and as message entities only when Telegram refuses a rich message.
+// 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
+// does not lose a message. A crash between the flush and the offset write
+// makes Telegram send the update again, and the message repeats once.
+//
+// A failed Bot API call waits and tries again, from minWait up to maxWait, or
+// as long as the Bot API asks. It never stops the agent.
+type TelegramBot struct {
+ api *TelegramAPI
+ owner int64
+ offsetPath string
+ logger *log.Logger
+ minWait time.Duration
+ maxWait time.Duration
+
+ mutex sync.Mutex
+ queue []Event
+ ready chan struct{}
}
// Notify queues event for the chat. It never blocks, so a slow network does not
-// stop the agent.
-func (b *telegramBot) Notify(event Event) {
+// stop the agent. The WhatsApp batches and the runs of the schedules do not go
+// to the chat: the reply of the agent tells the user what needs the user.
+func (b *TelegramBot) Notify(event Event) {
switch event.Kind {
- case "busy", "idle", "reply", "error", "notice":
+ case "busy", "idle", "reply", "error", "notice", "subagent":
+ case "work":
+ if event.Source == whatsappSource || event.Source == scheduleSource {
+ return
+ }
case "user":
if event.Source == telegramSource {
return
// Run polls for the messages of the owner and sends the queued events to the
// chat until ctx ends. It returns an error only when a message or the offset
// cannot be written, because then the bot would lose or repeat messages.
-func (b *telegramBot) Run(ctx context.Context, l *loop) error {
+func (b *TelegramBot) Run(ctx context.Context, l *TurnLoop, whatsapp *WhatsApp) error {
ctx, cancel := context.WithCancel(ctx)
defer cancel()
b.send(ctx)
}()
- err := b.poll(ctx, l)
+ err := b.poll(ctx, l, whatsapp)
cancel()
sender.Wait()
}
// send sends each queued event to the chat in order until ctx ends. While a
-// turn runs, it shows the typing action every typingInterval and after each
-// message, because a message ends the action.
-func (b *telegramBot) send(ctx context.Context) {
- ticker := time.NewTicker(typingInterval)
+// turn runs, it shows the typing action every telegramTypingInterval and after
+// each message, because a message ends the action.
+func (b *TelegramBot) send(ctx context.Context) {
+ ticker := time.NewTicker(telegramTypingInterval)
defer ticker.Stop()
busy := false
case "busy":
busy = true
b.typing(ctx)
- ticker.Reset(typingInterval)
+ ticker.Reset(telegramTypingInterval)
case "idle":
busy = false
default:
- for _, part := range botParts(event) {
- b.deliver(ctx, part)
- }
+ b.post(ctx, event)
if busy {
b.typing(ctx)
}
}
+// poll gets the updates from the stored offset on and handles each one, until
+// ctx ends. Each update is handled to its end also when ctx ends during it, so
+// a stop does not repeat its message.
+func (b *TelegramBot) poll(ctx context.Context, l *TurnLoop, whatsapp *WhatsApp) error {
+ offset, err := telegramLoadOffset(b.offsetPath)
+ if err != nil {
+ return err
+ }
+
+ wait := b.minWait
+ for ctx.Err() == nil {
+ updates, err := b.api.GetUpdates(ctx, offset)
+ if ctx.Err() != nil {
+ return nil
+ }
+
+ if err != nil {
+ _, asked := telegramRetryable(err)
+ wait = b.pause(ctx, err, wait, asked)
+
+ continue
+ }
+
+ wait = b.minWait
+ for _, update := range updates {
+ if ctx.Err() != nil {
+ return nil
+ }
+
+ err = b.handle(context.WithoutCancel(ctx), l, whatsapp, update)
+ if err != nil {
+ return err
+ }
+
+ offset = update.UpdateID + 1
+ err = telegramSaveOffset(b.offsetPath, offset)
+ if err != nil {
+ return err
+ }
+ }
+ }
+
+ return nil
+}
+
// next removes the first queued event and returns it.
-func (b *telegramBot) next() (Event, bool) {
+func (b *TelegramBot) next() (Event, bool) {
b.mutex.Lock()
defer b.mutex.Unlock()
// typing shows the typing action once. A failure is not logged, because the
// next message or poll logs the state of the network.
-func (b *telegramBot) typing(ctx context.Context) {
+func (b *TelegramBot) typing(ctx context.Context) {
_ = b.api.SendTyping(ctx, b.owner)
}
-// 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, part.text, part.entities)
- if err == nil || ctx.Err() != nil {
- return
+// post sends event to the chat. A reply goes as rich messages of its Markdown,
+// with each < and & outside code escaped by telegramEscapeTags and then split
+// with telegramSplitRich, so that the length limit counts the escaped text.
+// Every other event goes as plain text, split with telegramSplitMessage.
+func (b *TelegramBot) post(ctx context.Context, event Event) {
+ if event.Kind != "reply" {
+ for _, text := range telegramSplitMessage(telegramText(event), telegramMessageUnits) {
+ b.deliver(ctx, TelegramPart{
+ text: text,
+ })
}
- 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)
- return
- }
+ return
+ }
- wait = b.pause(ctx, err, wait, asked)
+ for _, markdown := range telegramSplitRich(telegramEscapeTags(event.Text), telegramRichBytes) {
+ b.deliverRich(ctx, markdown)
}
}
// pause logs err and waits the longer of wait and asked, or until ctx ends. It
// returns the wait of the next failure: twice wait, up to maxWait.
-func (b *telegramBot) pause(ctx context.Context, err error, wait, asked time.Duration) time.Duration {
+func (b *TelegramBot) pause(ctx context.Context, err error, wait, asked time.Duration) time.Duration {
delay := max(wait, asked)
b.logger.Printf("%v (next try in %s)", err, delay)
return min(2*wait, b.maxWait)
}
-// poll gets the updates from the stored offset on and handles each one, until
-// ctx ends. Each update is handled to its end also when ctx ends during it, so
-// a stop does not repeat its message.
-func (b *telegramBot) poll(ctx context.Context, l *loop) error {
- offset, err := loadOffset(b.offsetPath)
- if err != nil {
- return err
- }
-
- wait := b.minWait
- for ctx.Err() == nil {
- updates, err := b.api.GetUpdates(ctx, offset)
- if ctx.Err() != nil {
- return nil
- }
-
- if err != nil {
- _, asked := retryable(err)
- wait = b.pause(ctx, err, wait, asked)
-
- continue
- }
-
- wait = b.minWait
- for _, update := range updates {
- if ctx.Err() != nil {
- return nil
- }
-
- err = b.handle(context.WithoutCancel(ctx), l, update)
- if err != nil {
- return err
- }
-
- offset = update.UpdateID + 1
- err = saveOffset(b.offsetPath, offset)
- if err != nil {
- return err
- }
- }
- }
-
- return nil
-}
-
// handle runs one update. A text message of the owner in the private chat goes
// to the agent, and handle returns when it is durable in the log. The line
-// /stop interrupts the turn. Any other message of the owner gets the answer
+// /stop interrupts the turn, the line /stop NAME stops the subagent NAME, and a
+// line that starts with /whatsapp runs a WhatsApp command on whatsapp, whose
+// answers go to the chat only. Any other message of the owner gets the answer
// that only text is supported. Every other update is ignored, and its content
// is not logged.
-func (b *telegramBot) handle(ctx context.Context, l *loop, update botUpdate) error {
+func (b *TelegramBot) handle(ctx context.Context, l *TurnLoop, whatsapp *WhatsApp, update TelegramUpdate) error {
message := update.Message
if message == nil || message.Chat.Type != "private" || message.Chat.ID != b.owner || message.From == nil || message.From.ID != b.owner {
b.logger.Print("update ignored: not a message of the owner in the private chat")
return nil
}
+ name, stop := stopSubagentName(message.Text)
+ args, isWhatsApp := whatsappCommandArgs(message.Text)
switch {
case message.Text == "":
- b.notice(textOnly)
+ b.notice(telegramTextOnly)
case strings.TrimSpace(message.Text) == stopCommand:
if !l.Interrupt() {
b.notice("No turn runs.")
}
+ case stop:
+ found, err := l.StopSubagent(name)
+ if err != nil {
+ return fmt.Errorf("stop subagent %s: %w", name, err)
+ }
+
+ if !found {
+ b.notice("No subagent " + name + " runs.")
+ }
+ case isWhatsApp:
+ whatsapp.Command(args, b.notice)
default:
_, err := l.Submit(telegramSource, message.Text)
if err != nil {
return nil
}
+// 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 TelegramPart) {
+ wait := b.minWait
+ for {
+ err := b.api.SendMessage(ctx, b.owner, part.text, part.entities)
+ if err == nil || ctx.Err() != nil {
+ return
+ }
+
+ var answer *TelegramError
+ 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 := telegramRetryable(err)
+ if !retry {
+ b.logger.Printf("message dropped: %v", err)
+ return
+ }
+
+ wait = b.pause(ctx, err, wait, asked)
+ }
+}
+
+// deliverRich sends markdown, escaped with telegramEscapeTags, to the chat as a
+// rich message. When the Bot API refuses it with HTTP 400 or 404, the message
+// was not sent, so deliverRich sends the text of the part once with message
+// entities, and the reply is not lost and does not repeat. Message entities
+// read no HTML, so the fallback gets the Markdown of telegramUnescapeTags, as
+// the model wrote it. It tries again after each failure that a later try can
+// fix, until ctx ends. It drops the message after any other failure.
+func (b *TelegramBot) deliverRich(ctx context.Context, markdown string) {
+ wait := b.minWait
+ for {
+ err := b.api.SendRichMessage(ctx, b.owner, markdown)
+ if err == nil || ctx.Err() != nil {
+ return
+ }
+
+ if telegramRejected(err) {
+ b.logger.Printf("rich message refused, the reply goes with entities: %v", err)
+ for _, part := range telegramReplyParts(telegramUnescapeTags(markdown)) {
+ b.deliver(ctx, part)
+ }
+
+ return
+ }
+
+ retry, asked := telegramRetryable(err)
+ if !retry {
+ b.logger.Printf("message dropped: %v", err)
+ return
+ }
+
+ wait = b.pause(ctx, err, wait, asked)
+ }
+}
+
// notice queues a short answer of the bot for the chat.
-func (b *telegramBot) notice(text string) {
+func (b *TelegramBot) notice(text string) {
b.Notify(Event{
Kind: "notice",
Text: text,
})
}
-// loadOffset reads the update offset at path. A missing file gives 0, which
-// asks for every update that Telegram keeps.
-func loadOffset(path string) (int64, error) {
+// TelegramPart is the text of one message to the chat, at most
+// telegramMessageUnits long, and its entities.
+type TelegramPart struct {
+ text string
+ entities []TelegramEntity
+}
+
+// TelegramOffsetFile is the content of the offset file.
+type TelegramOffsetFile struct {
+ Offset int64 `json:"offset"`
+}
+
+// telegramLoadOffset reads the update offset at path. A missing file gives 0,
+// which asks for every update that Telegram keeps.
+func telegramLoadOffset(path string) (int64, error) {
data, err := os.ReadFile(path)
if errors.Is(err, os.ErrNotExist) {
return 0, nil
return 0, fmt.Errorf("read update offset: %w", err)
}
- var file offsetFile
+ var file TelegramOffsetFile
err = json.Unmarshal(data, &file)
if err != nil {
return 0, fmt.Errorf("%s: %w", path, err)
return file.Offset, nil
}
-// saveOffset replaces the update offset at path.
-func saveOffset(path string, offset int64) error {
- data, err := json.Marshal(offsetFile{
+// telegramSaveOffset replaces the update offset at path.
+func telegramSaveOffset(path string, offset int64) error {
+ data, err := json.Marshal(TelegramOffsetFile{
Offset: offset,
})
if err != nil {
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 {
- switch event.Kind {
- case "user":
- return "[" + event.Source + "] " + event.Text
- case "error":
- return "Error: " + event.Text
- default:
- return event.Text
- }
-}
-
-// 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
+// telegramSplitMessage 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
// never cuts a character.
-func splitMessage(text string, limit int) []string {
+func telegramSplitMessage(text string, limit int) []string {
var parts []string
for {
- end := prefixEnd(text, limit)
+ end := telegramPrefixEnd(text, limit)
if end == len(text) {
return append(parts, text)
}
}
}
-// prefixEnd returns the byte length of the longest prefix of text with at most
-// limit UTF-16 code units.
-func prefixEnd(text string, limit int) int {
- units := 0
- for index, char := range text {
- size := 1
- if char > 0xFFFF {
- size = 2
- }
-
- if units+size > limit {
- return index
- }
-
- units += size
+// telegramText returns the text of event for the chat. A user message of
+// another client has its source as a mark. A subagent shows only its start and
+// how its run ended, because the reply of the agent carries the content of the
+// report.
+func telegramText(event Event) string {
+ switch event.Kind {
+ case "user":
+ return "[" + event.Source + "] " + event.Text
+ case "subagent":
+ return "[" + event.Text + "] started"
+ case "work":
+ return "[" + event.Source + "] " + event.Status
+ case "error":
+ return "Error: " + event.Text
+ default:
+ return event.Text
}
-
- return len(text)
}
-// splitRich cuts the Markdown of a reply into parts of at most limit bytes. It
-// cuts after a blank line outside a code block, so a table, a code block, or a
-// paragraph stays whole. When no such cut fits in a part, it cuts after the
-// last line break outside a code block, then after the last line break in a
-// code block, which it closes at the end of the part and opens again in the
-// next part with the same fence line. A line longer than limit is cut at the
-// limit. It never cuts a character.
-func splitRich(markdown string, limit int) []string {
+// telegramSplitRich cuts the Markdown of a reply into parts of at most limit
+// bytes. It cuts after a blank line outside a code block, so a table, a code
+// block, or a paragraph stays whole. When no such cut fits in a part, it cuts
+// after the last line break outside a code block, then after the last line
+// break in a code block, which it closes at the end of the part and opens again
+// in the next part with the same fence line. A line longer than limit is cut at
+// the limit, or before an & in the four bytes before the limit, so that it does
+// not cut an entity of telegramEscapeTags. It never cuts a character.
+func telegramSplitRich(markdown string, limit int) []string {
var parts []string
for len(markdown) > limit {
- cut, fence, opening := richCut(markdown, limit)
+ cut, fence, opening := telegramRichCut(markdown, limit)
if fence == "" {
parts = append(parts, markdown[:cut])
markdown = markdown[cut:]
return append(parts, markdown)
}
-// richCut returns where splitRich cuts markdown, which is longer than limit.
-// For a cut in a code block, it also returns the fence that closes the block
-// and the line that opens it. Each part before a cut holds text other than
-// space, and a cut in a code block leaves room for the fence, so each cut makes
-// the rest shorter.
-func richCut(markdown string, limit int) (int, string, string) {
+// telegramReplyParts returns the messages of the Markdown of a reply with
+// message entities. A reply that has no text left after the conversion, such as
+// an empty code block, goes as its Markdown.
+func telegramReplyParts(markdown string) []TelegramPart {
+ text, entities := telegramMarkdownEntities(markdown)
+ if strings.TrimSpace(text) == "" {
+ text, entities = markdown, nil
+ }
+
+ return telegramSplitEntities(text, entities, telegramMessageUnits)
+}
+
+// telegramPrefixEnd returns the byte length of the longest prefix of text with
+// at most limit UTF-16 code units.
+func telegramPrefixEnd(text string, limit int) int {
+ units := 0
+ for index, char := range text {
+ size := 1
+ if char > 0xFFFF {
+ size = 2
+ }
+
+ if units+size > limit {
+ return index
+ }
+
+ units += size
+ }
+
+ return len(text)
+}
+
+// telegramRichCut returns where telegramSplitRich cuts markdown, which is
+// longer than limit. For a cut in a code block, it also returns the fence that
+// closes the block and the line that opens it. Each part before a cut holds
+// text other than space, and a cut in a code block leaves room for the fence,
+// so each cut makes the rest shorter.
+func telegramRichCut(markdown string, limit int) (int, string, string) {
blank, line, code := 0, 0, 0
var fence, opening, inFence, inOpening string
for start := 0; start < limit; {
end += start + 1
text := strings.TrimRight(markdown[start:end], "\r\n")
- _, opens := codeFence(text)
+ _, opens := telegramCodeFence(text)
switch {
case fence != "":
- if closesFence(text, fence) {
+ if telegramClosesFence(text, fence) {
fence = ""
} else if end > len(opening)+1 && end+len(fence)+1 <= limit {
code, inFence, inOpening = end, fence, opening
cut--
}
+ start := max(cut-len("&")+1, 0)
+ entity := strings.LastIndexByte(markdown[start:cut], '&')
+ if entity >= 0 && start+entity > 0 {
+ cut = start + entity
+ }
+
return cut, "", ""
}
+
+// telegramSplitEntities cuts text into parts with telegramSplitMessage, 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 telegramSplitEntities(text string, entities []TelegramEntity, limit int) []TelegramPart {
+ var parts []TelegramPart
+ start := 0
+ for _, part := range telegramSplitMessage(text, limit) {
+ end := start + telegramUTF16Units(part)
+ var kept []TelegramEntity
+ 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, TelegramPart{
+ text: part,
+ entities: kept,
+ })
+
+ start = end
+ }
+
+ return parts
+}
projects / onechat / blobdiff