From 5341cb676aa0e3c304f914e51cc0818ee43c070c Mon Sep 17 00:00:00 2001
From: Loic Coenen <loic@visua.com>
Date: Thu, 14 May 2026 14:56:11 +0000
Subject: [PATCH] feat: add status FIFO and parse status line in client

---
 client/makefile     |  2 +-
 client/src/tui.c    | 22 ++++++++++++++++++++++
 engine/src/looper.c | 42 ++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 65 insertions(+), 1 deletion(-)

diff --git a/client/makefile b/client/makefile
index 3d03497..5eb60bf 100644
--- a/client/makefile
+++ b/client/makefile
@@ -4,7 +4,7 @@ CFLAGS = -Wall -Wextra -Wpedantic -std=c11
 all: test_status_parse
 
 test_status_parse: tests/test_status_parse.c
-	$(CC) $(CFLAGS) -I../src -o test_status_parse tests/test_status_parse.c ../src/tui.c -lncurses
+	$(CC) $(CFLAGS) -Isrc -o test_status_parse tests/test_status_parse.c src/tui.c -lncurses
 
 test: test_status_parse
 	./test_status_parse
diff --git a/client/src/tui.c b/client/src/tui.c
index 28d4214..cef5bc3 100644
--- a/client/src/tui.c
+++ b/client/src/tui.c
@@ -63,6 +63,28 @@ typedef struct {
 } FuzzySearch;
 static FuzzySearch fuzzy_search = {0};
 
+/* ---------- Parse status line from engine status FIFO ---------- */
+typedef enum { STATE_IDLE, STATE_RECORD, STATE_LOOPING, STATE_PAUSED } ChannelState;
+
+bool parse_status_line(const char *line, int *ch, int *scene, ChannelState *state) {
+    int sta;
+    if (sscanf(line, "CH=%d SC=%d STATE=%d", ch, scene, &sta) == 3) {
+        if (sta >= 0 && sta <= 3) {
+            *state = (ChannelState)sta;
+            return true;
+        }
+    }
+    /* try text-based format */
+    char state_str[32];
+    if (sscanf(line, "CH=%d SC=%d STATE=%31s", ch, scene, state_str) != 3)
+        return false;
+    if (strcmp(state_str, "IDLE") == 0)    { *state = STATE_IDLE;    return true; }
+    if (strcmp(state_str, "RECORD") == 0)  { *state = STATE_RECORD;  return true; }
+    if (strcmp(state_str, "LOOPING") == 0) { *state = STATE_LOOPING; return true; }
+    if (strcmp(state_str, "PAUSED") == 0)  { *state = STATE_PAUSED;  return true; }
+    return false;
+}
+
 /* ---------- State to color (dummy: all white) ---------- */
 static int state_to_color(ClipState s) { (void)s; return COLOR_EMPTY; }
 
diff --git a/engine/src/looper.c b/engine/src/looper.c
index 0ce3d66..8ce993c 100644
--- a/engine/src/looper.c
+++ b/engine/src/looper.c
@@ -5,6 +5,9 @@
 #include "midi.h"
 #include "queue.h"
 #include <jack/jack.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
 #include <jack/midiport.h>
 #include <math.h>
 #include <stdatomic.h>
@@ -12,6 +15,39 @@
 #include <stdlib.h>
 #include <string.h>
 
+#define STATUS_FIFO "/tmp/looper_status"
+
+static void looper_write_status(void) {
+    int fd = open(STATUS_FIFO, O_WRONLY | O_NONBLOCK);
+    if (fd < 0)
+        return;
+    struct channel_t *cur = get_channels_array();
+    int cap = atomic_load(&channel_capacity);
+    char buf[256];
+    for (int ch = 0; ch < cap; ch++) {
+        if (!atomic_load(&cur[ch].active))
+            continue;
+        int sc_idx = atomic_load(&cur[ch].current_scene);
+        int state = atomic_load(&cur[ch].scenes[sc_idx].state);
+        const char *state_str;
+        switch (state) {
+            case STATE_IDLE:    state_str = "IDLE";    break;
+            case STATE_RECORD:  state_str = "RECORD";  break;
+            case STATE_LOOPING: state_str = "LOOPING"; break;
+            case STATE_PAUSED:  state_str = "PAUSED";  break;
+            default:            state_str = "UNKNOWN";
+        }
+        int n = snprintf(buf, sizeof(buf),
+                         "CH=%d SC=%d STATE=%s\n",
+                         ch, sc_idx, state_str);
+        if (n > 0) {
+            int ret = write(fd, buf, n);
+            (void)ret;
+        }
+    }
+    close(fd);
+}
+
 /* Global state (shared across files) */
 struct channel_t *_Atomic channels = NULL;
 atomic_int channel_capacity = 0;
@@ -393,6 +429,9 @@ void jack_shutdown_cb(void *arg) {
  * looper initialisation
  * ---------------------------------------------------------------- */
 int looper_init(jack_client_t *client) {
+  /* create status FIFO (ignore if already exists) */
+  mkfifo(STATUS_FIFO, 0666);
+
   queue_init(&cmd_queue);
   queue_init(&cmd_queue_main_midi);
   queue_init(&cmd_queue_main_fifo);
@@ -631,4 +670,7 @@ void looper_process_commands(jack_client_t *client) {
       pending_old = NULL;
     }
   }
+
+  /* write current state to status FIFO */
+  looper_write_status();
 }