implement message sending to channels

libdc/include/dc/api.h

@@ -90,6 +90,12 @@ bool dc_api_create_channel(dc_api_t api, dc_account_t login,
  */
 bool dc_api_get_messages(dc_api_t api, dc_account_t login, dc_channel_t c);
 
+/**
+ * post a message to the given channel
+ */
+bool dc_api_post_message(dc_api_t api, dc_account_t login,
+                         dc_channel_t c, dc_message_t m);
+
 /**
  * Fetch a list of friends of the login account "login". The friends are stored
  * within the login object.

libdc/include/dc/message.h

@@ -10,6 +10,7 @@ struct dc_message_;
 typedef struct dc_message_ *dc_message_t;
 
 dc_message_t dc_message_new(void);
+dc_message_t dc_message_new_content(char const *s, int len);
 dc_message_t dc_message_from_json(json_t *j);
 json_t *dc_message_to_json(dc_message_t m);
 

libdc/include/dc/session.h

@@ -52,6 +52,12 @@ bool dc_session_has_token(dc_session_t s);
  */
 dc_account_t dc_session_me(dc_session_t s);
 
+/**
+ * Return the API handle in use by the session. Do not unref the reference
+ * and if you need it for something else, dc_ref() it yourself.
+ */
+dc_api_t dc_session_api(dc_session_t s);
+
 /**
  * access to the internal account cache
  */

libdc/src/api-channel.c

@@ -2,6 +2,36 @@
 
 #include "internal.h"
 
+bool dc_api_post_message(dc_api_t api, dc_account_t login,
+                         dc_channel_t c, dc_message_t m)
+{
+    bool ret = false;
+    char *url = NULL;
+    json_t *j = NULL, *reply = NULL;
+
+    return_if_true(api == NULL || login == NULL || m == NULL, false);
+    return_if_true(dc_message_content(m) == NULL, false);
+
+    asprintf(&url, "channels/%s/messages", dc_channel_id(c));
+    goto_if_true(url == NULL, cleanup);
+
+    j = dc_message_to_json(m);
+    goto_if_true(j == NULL, cleanup);
+
+    reply = dc_api_call_sync(api, "POST", TOKEN(login), url, j);
+    goto_if_true(reply != NULL, cleanup);
+
+    ret = true;
+
+cleanup:
+
+    free(url);
+    json_decref(j);
+    json_decref(reply);
+
+    return ret;
+}
+
 bool dc_api_get_messages(dc_api_t api, dc_account_t login, dc_channel_t c)
 {
     bool ret = false;

libdc/src/message.c

@@ -40,6 +40,24 @@ dc_message_t dc_message_new(void)
     return dc_ref(m);
 }
 
+dc_message_t dc_message_new_content(char const *s, int len)
+{
+    dc_message_t m = dc_message_new();
+    return_if_true(m == NULL, NULL);
+
+    if (len < 0) {
+        len = strlen(s);
+    }
+
+    m->content = strndup(s, len);
+    if (m->content == NULL) {
+        dc_unref(m);
+        return NULL;
+    }
+
+    return m;
+}
+
 dc_message_t dc_message_from_json(json_t *j)
 {
     dc_message_t m = NULL;

libdc/src/session.c

@@ -227,6 +227,12 @@ bool dc_session_has_token(dc_session_t s)
     return dc_account_has_token(s->login);
 }
 
+dc_api_t dc_session_api(dc_session_t s)
+{
+    return_if_true(s == NULL, NULL);
+    return s->api;
+}
+
 dc_account_t dc_session_me(dc_session_t s)
 {
     return_if_true(s == NULL, NULL);