1 files changed, 58 insertions, 16 deletions
diff --git a/telebot.scm b/telebot.scm
index 0a24973..8d30013 100644
--- a/telebot.scm
+++ b/telebot.scm
@@ -1,34 +1,76 @@
-(module telebot (get-me get-updates send-message)
+(module telebot (get-me
+                 get-updates
+                 send-message
+                 forward-message)
   (import chicken scheme)
+  (use srfi-1)
   (use openssl)
   (use http-client)
   (use medea)
 
   (define api-base "https://api.telegram.org/bot")
 
+  ;;; helper functions
+
   (define (get-query-url token method)
     (string-append api-base token "/" method))
 
+  (define (clean-query-parameters parameters)
+    (let ((cleaned-parameters (remove (lambda (p) (equal? #f (cdr p)))
+                                      parameters)))
+      (if (null-list? cleaned-parameters)
+        #f
+        cleaned-parameters)))
+
+  ;;; plain API wrappers, returning deserialized JSON
+
   (define (get-me token)
     (with-input-from-request (get-query-url token "getMe")
                              #f
                              read-json))
 
-  (define (get-updates token)
-    (with-input-from-request (get-query-url token "getUpdates")
-                             #f
-                             read-json))
+  (define (get-updates token
+                       #!key offset
+                             limit
+                             timeout)
+    (with-input-from-request
+      (get-query-url token "getUpdates")
+      (clean-query-parameters
+        (list (cons 'offset  offset)
+              (cons 'limit   limit)
+              (cons 'timeout timeout)))
+      read-json))
 
-  (define (send-message token chat-id text)
-    (with-input-from-request (get-query-url token "sendMessage")
-                             (list (cons 'chat_id chat-id)
-                                   (cons 'text    text))
-                             read-json))
+  (define (send-message token
+                        #!key chat-id
+                              text
+                              parse-mode
+                              disable-web-page-preview
+                              disable-notification
+                              reply-to-message-id
+                              reply-markup)
+    (with-input-from-request
+      (get-query-url token "sendMessage")
+      (clean-query-parameters
+        (list (cons 'chat_id                  chat-id)
+              (cons 'text                     text)
+              (cons 'parse_mode               parse-mode)
+              (cons 'disable_web_page_preview disable-web-page-preview)
+              (cons 'disable_notification     disable-notification)
+              (cons 'reply_to_message_id      reply-to-message-id)
+              (cons 'reply_markup             reply-markup)))
+      read-json))
 
-  (define (forward-message token chat-id from-chat-id message-id)
-    (with-input-from-request (get-query-url token "forwardMessage")
-                             (list (cons 'chat_id      chat-id)
-                                   (cons 'from_chat_id from-chat-id)
-                                   (cons 'message_id   message-id))
-                             read-json))
+  (define (forward-message token
+                           #!key chat-id
+                                 from-chat-id
+                                 message-id
+                                 disable-notification)
+    (with-input-from-request
+      (get-query-url token "forwardMessage")
+      (list (cons 'chat_id              chat-id)
+            (cons 'from_chat_id         from-chat-id)
+            (cons 'message_id           message-id)
+            (cons 'disable_notification disable-notification))
+      read-json))
 )