[jsonapi] Make updating of currently playing track metadata easier

Update to commit #aaffa4a that makes it easier to update currently playing
track, user can use "now_playing" instead of getting the queue item id.

README_JSON_API.md

@@ -529,8 +529,8 @@ curl -X PUT "http://localhost:3689/api/outputs/0/toggle"
 | GET       | [/api/queue](#list-queue-items)                             | Get a list of queue items            |
 | PUT       | [/api/queue/clear](#clearing-the-queue)                     | Remove all items from the queue      |
 | POST      | [/api/queue/items/add](#adding-items-to-the-queue)          | Add items to the queue               |
-| PUT       | [/api/queue/items/{id}](#updating-a-queue-item)             | Updating a queue item in the queue   |
-| DELETE    | [/api/queue/items/{id}](#removing-a-queue-item)             | Remove a queue item form the queue   |
+| PUT       | [/api/queue/items/{id}|now_playing](#updating-a-queue-item) | Updating a queue item in the queue   |
+| DELETE    | [/api/queue/items/{id}](#removing-a-queue-item)             | Remove a queue item from the queue   |
 
 
 
@@ -699,6 +699,10 @@ Update or move a queue item in the current queue
 ```http
 PUT /api/queue/items/{id}
 ```
+or
+```http
+PUT /api/queue/items/now_playing
+```
 
 **Path parameters**
 
@@ -706,6 +710,8 @@ PUT /api/queue/items/{id}
 | --------------- | -------------------- |
 | id              | Queue item id        |
 
+(or use now_playing to update the currenly playing track)
+
 **Query parameters**
 
 | Parameter       | Value                                                       |
@@ -733,6 +739,10 @@ curl -X PUT "http://localhost:3689/api/queue/items/3?new_position=0"
 curl -X PUT "http://localhost:3689/api/queue/items/3?title=Awesome%20title&artwork_url=http%3A%2F%2Fgyfgafguf.dk%2Fimages%2Fpige3.jpg"
 ```
 
+```shell
+curl -X PUT "http://localhost:3689/api/queue/items/now_playing?title=Awesome%20title&artwork_url=http%3A%2F%2Fgyfgafguf.dk%2Fimages%2Fpige3.jpg"
+```
+
 ### Removing a queue item
 
 Remove a queue item from the current queue

README_RADIO_STREAMS.md

@@ -43,7 +43,8 @@ Metadata:
 ```
 
 In the above, first fix is the blank name, second is the image artwork.
-### 1) Stream Name/Title
+
+### 1) Set stream name/title via the M3U file
 Set the name with an EXTINF tag in the m3u playlist file:
 
 ```
@@ -57,7 +58,7 @@ Length is -1 since it's a stream, `<Artist Name>` was left blank since
 `StreamTitle` is accurate in the Metadata but `<Artist Title>` was set to
 `My Radio Stream Name` since `icy-name` was blank.
 
-### 2) Artwork (and track duration)
+### 2) StreamUrl is a JSON file with metadata
 If `StreamUrl` does not point directly to an artwork file then the link may be
 to a json file that contains an artwork link. If so, you can make forked-daapd
 download the file automatically and search for an artwork link, and also track
@@ -91,6 +92,15 @@ curl -X PUT "http://localhost:3689/api/settings/misc/streamurl_keywords_artwork_
 
 If you want multiple search phrases then comma separate, e.g. "duration,length".
 
+### 3) Set metadata with a custom script
+If your radio station publishes metadata via another method than the above, e.g.
+just on their web site, then you will have to write a script that pulls the
+metadata and then pushes it to forked-daapd. To update metadata for the
+currently playing radio station use something like this JSON API request:
+
+```shell
+curl -X PUT "http://localhost:3689/api/queue/items/now_playing?title=Awesome%20title&artwork_url=http%3A%2F%2Fgyfgafguf.dk%2Fimages%2Fpige3.jpg"
+```
 
 If your radio station is not returning any artwork links, you can also just make
 a static artwork by placing a png/jpg in the same directory as the m3u, and with

src/httpd_jsonapi.c

@@ -2533,10 +2533,9 @@ jsonapi_reply_queue_tracks_add(struct httpd_request *hreq)
 }
 
 static int
-update_pos(uint32_t item_id, const char *new)
+update_pos(uint32_t item_id, const char *new, char shuffle)
 {
   uint32_t new_position;
-  struct player_status status;
   int ret;
 
   if (safe_atou32(new, &new_position) < 0)
@@ -2545,8 +2544,7 @@ update_pos(uint32_t item_id, const char *new)
       return HTTP_BADREQUEST;
     }
 
-  player_get_status(&status);
-  ret = db_queue_move_byitemid(item_id, new_position, status.shuffle);
+  ret = db_queue_move_byitemid(item_id, new_position, shuffle);
   if (ret < 0)
     {
       DPRINTF(E_LOG, L_WEB, "Moving item '%d' to new position %d failed\n", item_id, new_position);
@@ -2567,22 +2565,29 @@ static int
 jsonapi_reply_queue_tracks_update(struct httpd_request *hreq)
 {
   struct db_queue_item *queue_item;
-  uint32_t item_id;
+  struct player_status status;
+  uint32_t item_id = 0;
   const char *param;
   bool is_changed;
   int ret;
 
-  ret = safe_atou32(hreq->uri_parsed->path_parts[3], &item_id);
-  if (ret < 0 || !(queue_item = db_queue_fetch_byitemid(item_id)))
+  player_get_status(&status);
+
+  if (strcmp(hreq->uri_parsed->path_parts[3], "now_playing") != 0)
+    safe_atou32(hreq->uri_parsed->path_parts[3], &item_id);
+  else
+    item_id = status.item_id;
+
+  if (!item_id || !(queue_item = db_queue_fetch_byitemid(item_id)))
     {
-      DPRINTF(E_LOG, L_WEB, "No valid item id given '%s'\n", hreq->uri_parsed->path);
+      DPRINTF(E_LOG, L_WEB, "No valid item id given, or now_playing given but not playing: '%s'\n", hreq->uri_parsed->path);
       return HTTP_BADREQUEST;
     }
 
   ret = HTTP_OK;
   is_changed = false;
   if ((param = evhttp_find_header(hreq->query, "new_position")))
-    ret = update_pos(item_id, param);
+    ret = update_pos(item_id, param, status.shuffle);
   if ((param = evhttp_find_header(hreq->query, "title")) && (is_changed = true))
     update_str(&queue_item->title, param);
   if ((param = evhttp_find_header(hreq->query, "album")) && (is_changed = true))
@@ -4378,6 +4383,7 @@ static struct httpd_uri_map adm_handlers[] =
     { EVHTTP_REQ_PUT,    "^/api/queue/clear$",                           jsonapi_reply_queue_clear },
     { EVHTTP_REQ_POST,   "^/api/queue/items/add$",                       jsonapi_reply_queue_tracks_add },
     { EVHTTP_REQ_PUT,    "^/api/queue/items/[[:digit:]]+$",              jsonapi_reply_queue_tracks_update },
+    { EVHTTP_REQ_PUT,    "^/api/queue/items/now_playing$",               jsonapi_reply_queue_tracks_update },
     { EVHTTP_REQ_DELETE, "^/api/queue/items/[[:digit:]]+$",              jsonapi_reply_queue_tracks_delete },
     { EVHTTP_REQ_POST,   "^/api/queue/save$",                            jsonapi_reply_queue_save},