Faster guider stop (#7)

* Add tracking of camera status

* Wait until cameras are idle

* Add stop --soft

* Do not rotate logs in watch_for_files

* Fix get_dark_subtracted_data when DARKFILE is None

src/lvmguider/actor/actor.py

@@ -22,6 +22,7 @@
 if TYPE_CHECKING:
     from lvmguider.guider import Guider
 
+
 __all__ = ["LVMGuiderActor"]
 
 
@@ -61,7 +62,7 @@ def __init__(self, *args, **kwargs):
         self.guider: Guider | None = None
         self.guide_task: asyncio.Task | None = None
 
-        # Track model of focuser associated to this telescope.
+        # Track model of the cameras and focuser associated to this telescope.
         self.models.actors.append(f"lvm.{self.telescope}.foc")
 
     @property

src/lvmguider/actor/commands/expose.py

@@ -14,6 +14,7 @@
 
 from lvmguider.actor import lvmguider_parser
 from lvmguider.maskbits import GuiderStatus
+from lvmguider.tools import wait_until_cameras_are_idle
 
 
 if TYPE_CHECKING:
@@ -51,6 +52,8 @@ async def expose(
 ):
     """Exposes the cameras without guiding."""
 
+    await wait_until_cameras_are_idle(command)
+
     # Force the cameras to check the last image.
     command.actor.cameras.reset_seqno()
 

src/lvmguider/actor/commands/focus.py

@@ -14,6 +14,7 @@
 
 from lvmguider.actor import lvmguider_parser
 from lvmguider.focus import Focuser
+from lvmguider.tools import wait_until_cameras_are_idle
 
 
 if TYPE_CHECKING:
@@ -68,6 +69,8 @@ async def focus(
 ):
     """Performs a focus sweep."""
 
+    await wait_until_cameras_are_idle(command)
+
     # Force the cameras to check the last image.
     command.actor.cameras.reset_seqno()
 

src/lvmguider/actor/commands/guide.py

@@ -18,6 +18,7 @@
 from lvmguider.actor import lvmguider_parser
 from lvmguider.guider import CriticalGuiderError, Guider
 from lvmguider.maskbits import GuiderStatus
+from lvmguider.tools import wait_until_cameras_are_idle
 
 
 if TYPE_CHECKING:
@@ -86,6 +87,8 @@ async def guide(
     if actor.status & GuiderStatus.NON_IDLE:
         return command.finish("Guider is not idle. Stop the guide loop.")
 
+    await wait_until_cameras_are_idle(command)
+
     # Force the cameras to check the last image.
     command.actor.cameras.reset_seqno()
 

src/lvmguider/actor/commands/stop.py

@@ -27,25 +27,28 @@
 
 
 @lvmguider_parser.command()
-@click.option("--now", is_flag=True, help="Aggressively stops the loop.")
-async def stop(command: GuiderCommand, now=False):
+@click.option("--soft", is_flag=True, help="Stops the guider less aggressively.")
+async def stop(command: GuiderCommand, soft: bool = False):
     """Stops the guide loop."""
 
-    status = command.actor.status
-    if status & GuiderStatus.IDLE:
+    if command.actor.guide_task is None or command.actor.guide_task.done():
+        command.actor.status = GuiderStatus.IDLE
         return command.finish("Guider is not active.")
 
-    if now:
-        if command.actor.guide_task and not command.actor.guide_task.done():
-            command.actor.guide_task.cancel()
-            with suppress(asyncio.CancelledError):
-                await command.actor.guide_task
-        command.actor.guider = None
-        command.actor.status = GuiderStatus.IDLE
-        return command.finish("Guider was forcibly stopped.")
+    if soft:
+        if command.actor.status & GuiderStatus.STOPPING:
+            return command.fail("Guider loop is already stopping.")
+
+        command.actor.status |= GuiderStatus.STOPPING
+        return command.finish("Stopping the guide loop.")
+
+    command.actor.guide_task.cancel()
+    with suppress(asyncio.CancelledError):
+        await command.actor.guide_task
+
+    command.actor.guider = None
+    command.actor.guide_task = None
 
-    if command.actor.status & GuiderStatus.STOPPING:
-        return command.fail("Guider loop is already stopping.")
+    command.actor.status = GuiderStatus.IDLE
 
-    command.actor.status |= GuiderStatus.STOPPING
-    return command.finish("Stopping the guide loop.")
+    return command.finish("Guider has been stopped.")

src/lvmguider/tools.py

@@ -529,16 +529,16 @@ def get_dark_subtracted_data(
     # Data in counts per second.
     data: ARRAY_2D_F32 = raw.data.copy().astype("f4") / exptime
 
+    dark_file = ""
+    dark_path = None
+
     if "PROC" in hdul:
         # Get data and subtract dark or fit background.
         dirname = hdul["PROC"].header.get("DIRNAME", path.parent)
         dark_file = hdul["PROC"].header.get("DARKFILE", "")
 
-        dark_path = pathlib.Path(dirname) / dark_file
-
-    else:
-        dark_file = ""
-        dark_path = None
+        if dark_file and dark_file != "":
+            dark_path = pathlib.Path(dirname) / dark_file
 
     if dark_file != "" and dark_path is not None and dark_path.exists():
         dark_raw = get_raw_extension(str(dark_path))
@@ -844,6 +844,36 @@ def get_raw_extension(file: AnyPath | fits.HDUList):
         return hdul[0]
 
 
+async def wait_until_cameras_are_idle(
+    command: GuiderCommand, timeout: float | None = 30.0, interval: float = 2.0
+):
+    """Blocks until all the AG cameras for the telescope are idle."""
+
+    agcam: str = f"lvm.{command.actor.telescope}.agcam"
+    elapsed: float = 0.0
+
+    while True:
+        status_cmd = await command.send_command(agcam, "status", internal=True)
+        if status_cmd.status.did_fail:
+            raise ValueError(f"Command '{agcam} status' failed.")
+
+        states: list[str] = []
+        for reply in status_cmd.replies:
+            if "status" in reply.message:
+                states.append(reply.message["status"]["camera_state"])
+
+        if all([state == "idle" for state in states]):
+            return True
+
+        if elapsed == 0:
+            command.warning("Waiting until cameras are idle.")
+        elif timeout is not None and elapsed >= timeout:
+            raise TimeoutError("Timed out waiting for cameras to become idle.")
+
+        await asyncio.sleep(interval)
+        elapsed += interval
+
+
 def isot_to_sjd(isot: str):
     """Converts ISOT format to SJD."""