Player: runtime source override and play-a-URL on /api/player

The player now owns the effective mode (config or override) and passes it
down: spotify_apply(enable) and hls_set_url(url) instead of both reading
source.mode from the config. /api/player/source forces spotify|hls|off
(config returns to the saved mode), /api/player/url plays an m3u8 now;
neither is saved. GET reports it in `forced`.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

CLAUDE.md

@@ -69,7 +69,7 @@ Repo: https://gitea.apointless.space/bsncubed/aes67-ESP32-P4
     - An old, long-idle session can get out of sync with the app: it sends empty Load frames ("No tracks in frame") instead of Pause/Play, so controls do nothing. Quitting and reopening Spotify on the Mac fixes it.
   - [x] failover (auto mode): no session or (with `failover_on_pause`) paused for `failover_delay_s` -> HLS; Spotify playing -> Spotify within ~1 s; 30 ms fades; HLS suspended while Spotify plays; cspot is held back (not drained) while it isn't Spotify's turn, so it resumes where it paused. Verified: no session -> HLS, play -> Spotify, pause stays (on_pause off), pause -> HLS after 5 s (on_pause on), play -> Spotify at the paused position.
     - Open: `aes67_tx resync` (TX 20-27 ms late) ~11 s after each switch to Spotify (seen 3 times); clicks at switches not yet checked in a recording; HLS start sometimes hits CDN read timeouts.
-  - [ ] /api/player: GET, transport (play/pause/toggle/stop/next/prev), seek and volume done (the app follows). Web UI progress bar (seek on release) done. Next: source override/url.
+  - [x] /api/player: GET, transport, seek, volume (the app follows), source override and url (runtime, not saved); web UI progress bar.
 - [ ] 8. Mono sum, gain, polish.
 
 ## Phase 2 (parked)

components/spotify/include/spotify.h

@@ -25,13 +25,14 @@ typedef void (*spotify_event_cb_t)(spotify_event_t ev, int value);
 // played out so far. Used to tell Spotify when a new track actually becomes audible.
 typedef uint32_t (*spotify_pos_cb_t)(void);
 
-// Registers the zeroconf endpoints (/spotify_info), starts the session task and applies the config.
+// Registers the zeroconf endpoints (/spotify_info) and starts the session task (disabled until
+// spotify_apply(true)).
 esp_err_t spotify_init(spotify_pcm_cb_t pcm, spotify_event_cb_t event, spotify_pos_cb_t written,
                        spotify_pos_cb_t played);
-// Re-read the "source" config: enabled (advertised, sessions accepted) when mode is spotify/auto and
-// the client credentials are set; otherwise not advertised and a running session is ended.
-// A new device name ends the session and re-advertises.
-void spotify_apply(void);
+// Enable (advertised, sessions accepted) when the player's mode needs Spotify and the client
+// credentials are set; otherwise not advertised and a running session is ended. Re-reads name and
+// credentials from the "source" config: a new device name ends the session and re-advertises.
+void spotify_apply(bool enable);
 typedef enum {
     SPOTIFY_CMD_PLAY, SPOTIFY_CMD_PAUSE, SPOTIFY_CMD_NEXT, SPOTIFY_CMD_PREV,
     SPOTIFY_CMD_SEEK,       // arg: position in ms

components/spotify/spotify.cpp

@@ -33,6 +33,7 @@ static std::shared_ptr<cspot::LoginBlob> s_blob;     // guarded by s_mutex
 static std::mutex s_mutex;
 static std::string s_name;                              // advertised device name ("" = not advertised)
 static std::atomic<bool> s_enabled{false};
+static std::atomic<bool> s_want{false};                 // last spotify_apply(): the player needs Spotify
 static std::atomic<bool> s_stop{false};                 // end the running session
 static std::atomic<bool> s_got_blob{false};
 static std::atomic<bool> s_in_session{false};           // session() running (its tasks may exist)
@@ -107,7 +108,7 @@ static void check_playback(const std::shared_ptr<cspot::SpircHandler> &handler)
 extern "C" void spotify_suspend(bool suspend)
 {
     if (!suspend) {
-        spotify_apply();
+        spotify_apply(s_want);
         return;
     }
     s_enabled = false;
@@ -500,15 +501,15 @@ static void spotify_task(void *arg)
     }
 }
 
-extern "C" void spotify_apply(void)
+extern "C" void spotify_apply(bool enable)
 {
+    s_want = enable;
     cJSON *src = cfg_get("source");
-    std::string mode = cJSON_GetObjectItemCaseSensitive(src, "mode")->valuestring;
     std::string name = cJSON_GetObjectItemCaseSensitive(src, "spotify_name")->valuestring;
     bool creds = cJSON_GetObjectItemCaseSensitive(src, "spotify_client_id")->valuestring[0] &&
                  cJSON_GetObjectItemCaseSensitive(src, "spotify_client_secret")->valuestring[0];
     cJSON_Delete(src);
-    bool want = (mode == "spotify" || mode == "auto") && creds;
+    bool want = enable && creds;
 
     if (!want || name != s_name) {
         // Disable, or re-advertise under a new name: end any session, drop the old entry.
@@ -523,7 +524,7 @@ extern "C" void spotify_apply(void)
     }
     if (!want) {
         s_state = !creds ? "no client credentials" : "disabled (source mode)";
-        if (!creds && (mode == "spotify" || mode == "auto")) {
+        if (!creds && enable) {
             ESP_LOGW(TAG, "not started: set the Spotify client ID and secret (web UI, Source)");
         }
         return;
@@ -558,6 +559,5 @@ extern "C" esp_err_t spotify_init(spotify_pcm_cb_t pcm, spotify_event_cb_t event
     if (xTaskCreate(spotify_task, "spotify", 32 * 1024, nullptr, 5, nullptr) != pdPASS) {
         return ESP_ERR_NO_MEM;
     }
-    spotify_apply();
-    return ESP_OK;
+    return ESP_OK;     // the player enables it (spotify_apply)
 }

main/hls.c

@@ -4,7 +4,6 @@
 #include <stdlib.h>
 #include <string.h>
 
-#include "aes67_cfg.h"
 #include "esp_crt_bundle.h"
 #include "esp_heap_caps.h"
 #include "esp_http_client.h"
@@ -13,7 +12,7 @@
 #include "freertos/FreeRTOS.h"
 #include "freertos/task.h"
 
-#define URL_MAX         384
+#define URL_MAX         HLS_URL_MAX
 #define PLAYLIST_MAX    (64 * 1024)
 #define MAX_SEGMENTS    64
 #define LIVE_BACK       3           // start this many segments behind the live edge
@@ -33,7 +32,9 @@ typedef struct {
 static hls_sink_t s_sink;
 static char *s_text;                // playlist buffer (PSRAM)
 static media_pl_t *s_pl;            // parsed media playlist (PSRAM)
-static char s_url[URL_MAX];         // configured URL
+static char s_url[URL_MAX];         // URL being played
+static char s_want_url[URL_MAX];    // from hls_set_url(), guarded by s_url_lock
+static portMUX_TYPE s_url_lock = portMUX_INITIALIZER_UNLOCKED;
 static char s_media_url[URL_MAX];
 static uint8_t *s_seg;              // current segment (PSRAM)
 static volatile unsigned s_suspended;   // HLS_SUSPEND_* bits
@@ -47,15 +48,18 @@ void hls_suspend(unsigned reason, bool suspend)
     }
 }
 
-// hls_url when source.mode needs HLS, else "".
+void hls_set_url(const char *url)
+{
+    taskENTER_CRITICAL(&s_url_lock);
+    strlcpy(s_want_url, url, sizeof(s_want_url));
+    taskEXIT_CRITICAL(&s_url_lock);
+}
+
 static void wanted_url(char *out, size_t n)
 {
-    cJSON *src = cfg_get("source");
-    const char *mode = cJSON_GetObjectItemCaseSensitive(src, "mode")->valuestring;
-    const char *url = cJSON_GetObjectItemCaseSensitive(src, "hls_url")->valuestring;
-    bool on = !strcmp(mode, "hls") || !strcmp(mode, "auto");
-    strlcpy(out, on ? url : "", n);
-    cJSON_Delete(src);
+    taskENTER_CRITICAL(&s_url_lock);
+    strlcpy(out, s_want_url, n);
+    taskEXIT_CRITICAL(&s_url_lock);
 }
 
 static bool still_wanted(void)

main/hls.h

@@ -10,7 +10,11 @@
 // Receives segment data in chunks (MPEG-TS etc.). Return false to abort the segment.
 typedef bool (*hls_sink_t)(const uint8_t *data, size_t len, bool segment_start);
 
+#define HLS_URL_MAX 384
+
 esp_err_t hls_start(hls_sink_t sink);
+// The playlist URL to play ("" = none). A different URL restarts fetching with it.
+void hls_set_url(const char *url);
 // Stop fetching (current download is abandoned) until resumed. Reasons are independent:
 // fetching runs only when no reason holds it.
 #define HLS_SUSPEND_OTA      (1 << 0)

main/player.c

@@ -29,6 +29,7 @@ static const char *TAG = "player";
 
 typedef enum { MODE_TONE, MODE_OFF, MODE_HLS, MODE_SPOTIFY, MODE_AUTO } mode_t_;
 static const char *const SRC_NAME[] = { "tone", "off", "hls", "spotify" };
+static const char *const MODE_NAME[] = { "tone", "off", "hls", "spotify", "auto" };
 
 static volatile mode_t_ s_mode = MODE_OFF;
 static volatile player_src_t s_src = PLAYER_SRC_OFF;     // what is playing now
@@ -40,6 +41,12 @@ static volatile bool s_sp_playing;      // Spotify has started playback and is n
 static volatile bool s_hls_paused;      // HLS paused via the API: not fetching, silence
 static audio_conv_t *s_spotify_conv;
 
+// Effective mode: the config's, or a runtime override from the API (not saved). Web server task.
+static mode_t_ s_cfg_mode = MODE_OFF;
+static char s_cfg_url[HLS_URL_MAX];
+static int s_forced = -1;                   // mode forced via /api/player/source|url, -1 = none
+static char s_forced_url[HLS_URL_MAX];      // from /api/player/url; "" = the config's URL
+
 // Failover (mode auto)
 static volatile int s_failover_delay_s = 5;
 static volatile bool s_failover_on_pause;
@@ -173,14 +180,22 @@ static void select_source(player_src_t src)
     s_target = src;     // player_read fades out and switches
 }
 
-void player_apply(const cJSON *source)
+// Apply the effective mode: Spotify on/off, the HLS URL, and the source to play.
+static void apply_mode(void)
 {
-    if (s_spotify_conv) {       // after player_init: Spotify follows mode / name / credentials live
-        spotify_apply();
+    static char applied_url[HLS_URL_MAX];
+    mode_t_ mode = s_forced >= 0 ? (mode_t_)s_forced : s_cfg_mode;
+    if (s_spotify_conv) {       // after spotify_init: follows mode / name / credentials live
+        spotify_apply(mode == MODE_SPOTIFY || mode == MODE_AUTO);
+    }
+    const char *url = mode != MODE_HLS && mode != MODE_AUTO ? "" : s_forced_url[0] ? s_forced_url : s_cfg_url;
+    if (strcmp(url, applied_url)) {
+        strlcpy(applied_url, url, sizeof(applied_url));
+        hls_set_url(url);
+        if (s_src == PLAYER_SRC_HLS) {
+            s_flush = true;     // another stream: don't finish the old one's buffer
+        }
     }
-    s_failover_delay_s = (int)cJSON_GetObjectItemCaseSensitive(source, "failover_delay_s")->valuedouble;
-    s_failover_on_pause = cJSON_IsTrue(cJSON_GetObjectItemCaseSensitive(source, "failover_on_pause"));
-    mode_t_ mode = mode_of(cJSON_GetObjectItemCaseSensitive(source, "mode")->valuestring);
     if (mode == s_mode) {
         return;
     }
@@ -196,6 +211,15 @@ void player_apply(const cJSON *source)
     }
 }
 
+void player_apply(const cJSON *source)
+{
+    s_failover_delay_s = (int)cJSON_GetObjectItemCaseSensitive(source, "failover_delay_s")->valuedouble;
+    s_failover_on_pause = cJSON_IsTrue(cJSON_GetObjectItemCaseSensitive(source, "failover_on_pause"));
+    s_cfg_mode = mode_of(cJSON_GetObjectItemCaseSensitive(source, "mode")->valuestring);
+    strlcpy(s_cfg_url, cJSON_GetObjectItemCaseSensitive(source, "hls_url")->valuestring, sizeof(s_cfg_url));
+    apply_mode();
+}
+
 /* ----- source side ----- */
 
 // Write converted 48 kHz frames, waiting for space at playback speed. Frames of a source that is
@@ -369,7 +393,7 @@ static esp_err_t send_player(httpd_req_t *req)
     bool sp = src == PLAYER_SRC_SPOTIFY && spotify_now_playing(&t);
     cJSON *o = cJSON_CreateObject();
     cJSON_AddStringToObject(o, "source", SRC_NAME[src]);
-    cJSON_AddNullToObject(o, "forced");
+    add_str_or_null(o, "forced", s_forced >= 0 ? MODE_NAME[s_forced] : NULL);
     cJSON_AddStringToObject(o, "state", src == PLAYER_SRC_OFF ? "stopped" : source_state(src));
     add_str_or_null(o, "artist", sp ? t.artist : NULL);
     add_str_or_null(o, "title", sp ? t.title : NULL);
@@ -438,7 +462,7 @@ static const char *transport(const char *cmd)
 // Small JSON body of a POST; NULL if missing or invalid.
 static cJSON *read_body(httpd_req_t *req)
 {
-    char buf[128];
+    char buf[HLS_URL_MAX + 128];     // fits {"url": ...}
     if (req->content_len == 0 || req->content_len >= sizeof(buf)) {
         return NULL;
     }
@@ -490,6 +514,43 @@ static esp_err_t seek_or_volume(httpd_req_t *req, bool seek)
     return send_player(req);
 }
 
+// POST /api/player/source {source: spotify|hls|off|config}, /api/player/url {url}: runtime override
+static esp_err_t force_source(httpd_req_t *req, bool url)
+{
+    cJSON *body = read_body(req);
+    const cJSON *v = cJSON_GetObjectItemCaseSensitive(body, url ? "url" : "source");
+    const char *s = cJSON_IsString(v) ? v->valuestring : "";
+    const char *err = NULL;
+    if (url) {
+        if (strncmp(s, "http://", 7) && strncmp(s, "https://", 8)) {
+            err = "expected {\"url\": \"http(s)://...m3u8\"}";
+        } else if (strlen(s) >= sizeof(s_forced_url)) {
+            err = "url too long";
+        } else {
+            s_forced = MODE_HLS;
+            strlcpy(s_forced_url, s, sizeof(s_forced_url));
+            if (s_hls_paused && s_src == PLAYER_SRC_HLS) {
+                hls_pause(false);   // a new stream starts playing
+            }
+        }
+    } else if (!strcmp(s, "config")) {
+        s_forced = -1;
+        s_forced_url[0] = '\0';
+    } else if (!strcmp(s, "spotify") || !strcmp(s, "hls") || !strcmp(s, "off")) {
+        s_forced = mode_of(s);
+        s_forced_url[0] = '\0';
+    } else {
+        err = "expected {\"source\": \"spotify|hls|off|config\"}";
+    }
+    if (!err) {
+        ESP_LOGI(TAG, "override: %s%s%s", s_forced >= 0 ? MODE_NAME[s_forced] : "none (config)",
+                 s_forced_url[0] ? " " : "", s_forced_url);
+        apply_mode();
+    }
+    cJSON_Delete(body);
+    return err ? httpd_resp_send_err(req, HTTPD_400_BAD_REQUEST, err) : send_player(req);
+}
+
 // POST /api/player/<cmd>
 static esp_err_t player_post(httpd_req_t *req)
 {
@@ -511,6 +572,9 @@ static esp_err_t player_post(httpd_req_t *req)
     if (!strcmp(name, "seek") || !strcmp(name, "volume")) {
         return seek_or_volume(req, name[0] == 's');
     }
+    if (!strcmp(name, "source") || !strcmp(name, "url")) {
+        return force_source(req, name[0] == 'u');
+    }
     return httpd_resp_send_err(req, HTTPD_404_NOT_FOUND, "unknown player command");
 }
 
@@ -535,6 +599,7 @@ esp_err_t player_init(void)
         return ESP_ERR_NO_MEM;
     }
     spotify_init(spotify_pcm, spotify_event, audio_ring_written, audio_ring_read_pos);
+    apply_mode();               // now with Spotify
     aes67_ota_on_update(on_ota);
     err = hls_start(decoder_feed);
     if (err != ESP_OK) {