refactor(daemon): use obs-events for file fetching

Instead of depending on watchdog, use the OBS event which is faster.

pyproject.toml

@@ -8,7 +8,6 @@ requires-python = ">=3.9"
 dependencies = [
   "obsws-python",
   "tomli-w",
-  "watchdog",
   "tqdm"
 ]
 

requirements.txt

@@ -1,5 +1,4 @@
 obsws-python==1.8.0
 tomli-w==1.1.0
 tqdm==4.67.2
-watchdog==6.0.0
 websocket-client==1.9.0

rewind/autostart.py

@@ -1,81 +0,0 @@
-#!/usr/bin/env python3
-import os
-import platform
-import shutil
-import subprocess
-
-from pathlib import Path
-
-APP_NAME = "rewind-daemon"
-
-def _find_executable():
-    path = shutil.which(APP_NAME)
-    if not path:
-        raise RuntimeError(f"{APP_NAME} not found in PATH")
-    return path
-
-def _run(cmd: list[str]):
-    result = subprocess.run(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE, text=True)
-    if result.returncode != 0:
-        raise RuntimeError(f"Command failed: {' '.join(cmd)}\n{result.stderr}")
-    return result
-
-def _install_linux(program_path: str):
-    systemd_dir = Path.home() / ".config/systemd/user"
-    systemd_dir.mkdir(parents=True, exist_ok=True)
-
-    obs_service = systemd_dir / "obs.service"
-    daemon_service = systemd_dir / "rewind-daemon.service"
-
-    obs_service.write_text("""[Unit]
-Description=OBS Studio
-After=graphical-session.target
-Wants=graphical-session.target
-
-[Service]
-# Ensure OBS sentinel files are cleaned up before starting the daemon
-ExecStartPre=-/usr/bin/rm -rf %h/.config/obs-studio/.sentinel
-ExecStart=obs --minimize-to-tray
-Restart=on-failure
-RestartSec=3
-
-[Install]
-WantedBy=default.target
-""")
-
-    daemon_service.write_text(f"""[Unit]
-Description=Rewind Daemon
-After=obs.service
-Requires=obs.service
-
-[Service]
-ExecStart={program_path}
-Restart=always
-RestartSec=5
-Environment=PYTHONUNBUFFERED=1
-
-[Install]
-WantedBy=default.target
-""")
-
-    _run(["systemctl", "--user", "daemon-reload"])
-
-    _run(["systemctl", "--user", "enable", "obs.service"])
-    _run(["systemctl", "--user", "enable", "rewind-daemon.service"])
-
-    _run(["systemctl", "--user", "start", "obs.service"])
-    _run(["systemctl", "--user", "start", "rewind-daemon.service"])
-
-    print("Installed and started OBS + rewind-daemon via systemd")
-
-def install():
-    system = platform.system()
-    program_path = _find_executable()
-
-    if system == "Linux":
-        _install_linux(program_path)
-    else:
-        raise RuntimeError(f"Autostart on OS {system} not compatible or not implemented")
-
-if __name__ == "__main__":
-    install()

rewind/cli.py

@@ -3,7 +3,7 @@ import sys
 import argparse
 
 from rewind.core import clip, mark, save, print_markers
-from rewind.autostart import install
+from rewind.os.main import enable_autostart, disable_autostart, start_daemon, stop_daemon
 from rewind.config import Config
 
 def build_clip_parser(subparsers: argparse._SubParsersAction) -> None:
@@ -36,19 +36,21 @@ def build_mark_parser(subparsers: argparse._SubParsersAction) -> None:
     mark_parser.add_argument(
         "-n", "--name",
         type=str,
-        required=True,
+        required=False,
         help="Name of the marker"
     )
 
 def build_list_parser(subparsers: argparse._SubParsersAction) -> None:
     list_parser = subparsers.add_parser("list", help="List all markers in the recording")
 
-def build_install_parser(subparsers: argparse._SubParsersAction) -> None:
-    subparsers.add_parser(
-        "install",
-        help="Enable background recording daemon",
-        description="Install and enable the rewind daemon using system autostart."
-    )
+def build_daemon_parser(subparsers: argparse._SubParsersAction) -> None:
+    daemon_parser = subparsers.add_parser("daemon", help="Control the rewind daemon")
+    daemon_sub = daemon_parser.add_subparsers(dest="daemon_command")
+    daemon_sub.add_parser("start", help="Start the daemon")
+    daemon_sub.add_parser("stop", help="Stop the daemon")
+    daemon_sub.add_parser("enable", help="Enable autostart for the daemon")
+    daemon_sub.add_parser("disable", help="Disable autostart for the daemon")
+
 
 def build_config_parser(subparsers: argparse._SubParsersAction) -> None:
     config_parser = subparsers.add_parser("config", help="View or edit config values")
@@ -73,7 +75,7 @@ def build_parser() -> argparse.ArgumentParser:
     build_mark_parser(sub)
     build_list_parser(sub)
     build_save_parser(sub)
-    build_install_parser(sub)
+    build_daemon_parser(sub)
     build_config_parser(sub)
 
     return parser
@@ -92,15 +94,24 @@ def main(argv=None) -> int:
             print_markers()
         elif args.command == "save":
             save(args.start, args.end)
-        elif args.command == "install":
-            install()
+        elif args.command == "daemon":
+            if args.daemon_command == "start":
+                start_daemon()
+            elif args.daemon_command == "stop":
+                stop_daemon()
+            elif args.daemon_command == "enable":
+                enable_autostart()
+            elif args.daemon_command == "disable":
+                disable_autostart()
+            else:
+                parser.error("Unknown daemon command: expected 'start' or 'stop'")
         elif args.command == "config":
             if args.config_command == "set":
                 cfg.set(args.key, args.value)
             elif args.config_command == "get":
                 print(cfg.get(args.key))
             else:
-                cfg.show()
+                parser.error("Unknown config command: expected 'get' or 'set'")
         else:
             parser.error("Unknown command")
     except Exception as e:

rewind/config.py

@@ -16,6 +16,7 @@ class Config:
         self._config_file = self._config_dir / _CONFIG_NAME
         self._data = self._load()
 
+    # Private
     def _load(self) -> dict:
         if not self._config_file.exists():
             self._config_dir.mkdir(parents=True, exist_ok=True)
@@ -28,57 +29,46 @@ class Config:
         with self._config_file.open("wb") as f:
             tomli_w.dump(self._data, f)
 
-    @property
-    def obs_host(self) -> str:
+    # Public
+    def get_obs_host(self) -> str:
         return self._data["obs"]["host"]
 
-    @obs_host.setter
-    def obs_host(self, value: str) -> None:
+    def set_obs_host(self, value: str) -> None:
         self._data["obs"]["host"] = value
         self._save()
 
-    @property
-    def obs_port(self) -> int:
+    def get_obs_port(self) -> int:
         return self._data["obs"]["port"]
 
-    @obs_port.setter
-    def obs_port(self, value: int) -> None:
+    def set_obs_port(self, value: int) -> None:
         self._data["obs"]["port"] = value
         self._save()
 
-    @property
-    def obs_password(self) -> str:
+    def get_obs_password(self) -> str:
         return self._data["obs"]["password"]
 
-    @obs_password.setter
-    def obs_password(self, value: str) -> None:
+    def set_obs_password(self, value: str) -> None:
         self._data["obs"]["password"] = value
         self._save()
 
-    @property
-    def max_record_time(self) -> int:
+    def get_max_record_time(self) -> int:
         return self._data["record"]["max_record_time"]
 
-    @max_record_time.setter
-    def max_record_time(self, value: int) -> None:
+    def set_max_record_time(self, value: int) -> None:
         self._data["record"]["max_record_time"] = value
         self._save()
 
-    @property
-    def clip_output(self) -> str:
+    def get_clip_output(self) -> str:
         return os.path.expanduser(self._data["record"]["clip_output"])
 
-    @clip_output.setter
-    def clip_output(self, value: str) -> None:
+    def set_clip_output(self, value: str) -> None:
         self._data["record"]["clip_output"] = value
         self._save()
 
-    @property
-    def vod_output(self) -> str:
+    def get_vod_output(self) -> str:
         return os.path.expanduser(self._data["record"]["vod_output"])
 
-    @vod_output.setter
-    def vod_output(self, value: str) -> None:
+    def set_vod_output(self, value: str) -> None:
         self._data["record"]["vod_output"] = value
         self._save()
 
@@ -97,8 +87,3 @@ class Config:
             raise KeyError(f"Unknown config key: {key!r}")
         self._data[section][field] = type(current)(value)
         self._save()
-
-    def show(self) -> None:
-        for section, values in self._data.items():
-            for field, value in values.items():
-                print(f"{section}.{field} = {value!r}")

rewind/core.py

@@ -1,17 +1,18 @@
 #!/usr/bin/env python3
 import os
 import datetime
-import subprocess
 
-from rewind.state import load_state, add_marker_to_state, remove_marker_from_state
 from rewind.config import Config
-from tqdm import tqdm
+from rewind.media import get_ts_files, concat_ts_files
+from rewind.state import load_state, add_marker_to_state, remove_marker_from_state
+
+config = Config()
 
 def clip(seconds_from_end: float) -> None:
     if seconds_from_end <= 0 or seconds_from_end > 600:
         raise ValueError("Clip length must be positive and less than or equal to 10 minutes")
 
-    clip_output = Config().clip_output
+    clip_output = config.get_clip_output()
     os.makedirs(clip_output, exist_ok=True)
 
     output_file_name = f"{datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S')}.mp4"
@@ -21,16 +22,18 @@ def clip(seconds_from_end: float) -> None:
     end_timestamp = datetime.datetime.now().timestamp()
     length = end_timestamp - start_timestamp
     
-    files, start_offset, end_offset = _get_ts_files(
+    ts_files = [f for f in load_state()["files"] if os.path.exists(f["path"])]
+    files, start_offset, end_offset = get_ts_files(
+        ts_files,
         start_timestamp,
         end_timestamp
     )
 
-    _concat_ts_files(files, start_offset, end_offset, length, output_path)
+    concat_ts_files(files, start_offset, end_offset, length, output_path)
     print(f"Created clip: {output_path}")
 
 def save(first_marker: str, second_marker: str):
-    vod_dir = Config().vod_output
+    vod_dir = config.get_vod_output()
     os.makedirs(vod_dir, exist_ok=True)
 
     first_timestamp = get_marker_timestamp(first_marker)
@@ -42,17 +45,20 @@ def save(first_marker: str, second_marker: str):
     output_file_name = f"{datetime.datetime.fromtimestamp(first_timestamp).strftime('%Y-%m-%d_%H:%M:%S')}-[{first_marker}-{second_marker}].mp4"
     output_path = os.path.join(vod_dir, output_file_name)
 
-    files, start_offset, end_offset = _get_ts_files(
+    ts_files = [f for f in load_state()["files"] if os.path.exists(f["path"])]
+
+    files, start_offset, end_offset = get_ts_files(
+        ts_files,
         first_timestamp,
         second_timestamp
     )
 
-    _concat_ts_files(files, start_offset, end_offset, second_timestamp - first_timestamp, output_path)
+    concat_ts_files(files, start_offset, end_offset, second_timestamp - first_timestamp, output_path)
     print(f"Created video file: {output_path}")
 
 def mark(name: str) -> None:
     if not name:
-        raise ValueError("Marker name cannot be empty")
+        name = datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S')
     
     add_marker_to_state(name)
     print(f"Added marker: {name}")
@@ -87,105 +93,4 @@ def marker_exists(name: str) -> bool:
         if marker["name"] == name:
             return True
     
-    return False
-
-"""
-Retrieves .ts files recorded between the specified timestamps.
-Returns a list of file paths and extra start and end offsets if needed.
-get_duration() is used as little as possible since it is slow.
-end_timestamp of a file is the start time of the next file.
-"""
-def _get_ts_files(start_timestamp: float, end_timestamp: float) -> tuple[list[str], float, float]:
-    ts_files = load_state()["files"]
-    selected_files = []
-    start_offset = 0.0
-    end_offset = 0.0
-
-    for i, file_info in enumerate(ts_files):
-        file_start = file_info["timestamp"]
-        file_end = ts_files[i + 1]["timestamp"] if i + 1 < len(ts_files) else get_duration(file_info["path"]) + file_start
-
-        if file_end <= start_timestamp:
-            continue
-        if file_start >= end_timestamp:
-            break
-
-        selected_files.append(file_info["path"])
-
-        if file_start <= start_timestamp < file_end:
-            start_offset = start_timestamp - file_start
-        if file_start < end_timestamp <= file_end:
-            end_offset = file_end - end_timestamp
-
-    return selected_files, start_offset, end_offset
-
-def _concat_ts_files(file_list: list[str], start_offset: float, end_offset: float, length: float, output_file: str) -> None:
-    with open("file_list.txt", "w") as f:
-        for file_path in file_list:
-            f.write(f"file '{file_path}'\n")
-
-    cmd = ["ffmpeg", "-y", "-hide_banner", "-loglevel", "error", "-nostats", "-progress", "pipe:1"]
-    if start_offset > 0:
-        cmd += ["-ss", str(start_offset)]
-    if end_offset > 0:
-        cmd += ["-t", str(length)]
-    cmd += ["-f", "concat", "-safe", "0", "-i", "file_list.txt", "-c", "copy"]
-    cmd.append(output_file)
-
-    process = subprocess.Popen(
-        cmd,
-        stdout=subprocess.PIPE,
-        stderr=subprocess.PIPE,
-        text=True,
-        bufsize=1,
-    )
-
-    init_ms_val = 0
-    init_ms_val_set = False
-
-    with tqdm(
-        total=length,
-        unit="s",
-        unit_scale=True,
-        unit_divisor=60,
-        desc="Processing",
-        leave=True,
-    ) as pbar:
-        for line in process.stdout:
-            line = line.strip()
-            
-
-            if line.startswith("out_time_ms="):
-                out_time_ms = int(line.split("=")[1])
-
-                if not init_ms_val_set:
-                    init_ms_val = out_time_ms
-                    init_ms_val_set = True
-                out_time_ms -= init_ms_val
-
-                seconds = abs(out_time_ms / 1_000_000)
-                pbar.n = min(seconds, length)
-                pbar.refresh()
-
-            elif line == "progress=end":
-                break
-
-    ret = process.wait()
-    os.remove("file_list.txt")
-
-    if ret != 0:
-        raise RuntimeError("ffmpeg failed")
-
-def get_duration(file_path: str) -> float:
-    result = subprocess.run(
-        ["ffprobe", "-v", "error", "-show_entries",
-         "format=duration", "-of",
-         "default=noprint_wrappers=1:nokey=1", file_path],
-        stdout=subprocess.PIPE,
-        stderr=subprocess.STDOUT
-    )
-
-    if result.returncode != 0:
-        raise RuntimeError(f"ffprobe failed for file {file_path}")
-
-    return float(result.stdout)
+    return False

rewind/daemon.py

@@ -6,8 +6,6 @@ import obsws_python as obs
 import logging
 import signal
 
-from watchdog.observers import Observer
-from watchdog.events import FileSystemEventHandler
 from rewind.paths import get_state_dir
 from rewind.config import Config
 from rewind.core import mark, marker_exists, remove_marker
@@ -16,7 +14,6 @@ from rewind.state import add_file_to_state, create_state_file_if_needed, cleanup
 running = True
 LOG_FILE =  get_state_dir() / "daemon.log"
 INTERVAL = 10
-SENTINEL_FILE = os.path.expanduser("~/.config/obs-studio/.sentinel")
 OBS_MAX_RETRIES = 5
 
 logger = logging.getLogger(__name__)
@@ -32,21 +29,26 @@ def shutdown(signum, frame):
 signal.signal(signal.SIGINT, shutdown)
 signal.signal(signal.SIGTERM, shutdown)
 
-def open_obs_connection(host: str, port: int, password: str, obs_max_retries: int) -> obs.ReqClient:
-    con = None
+def open_obs_connection(host: str, port: int, password: str, obs_max_retries: int) -> dict[str, obs.ReqClient | obs.EventClient]:
+    req = None
+    event = None
     init_sleep = 1
 
     for _ in range(obs_max_retries):
         try:
-            con = obs.ReqClient(host=host, port=port, password=password)
+            req = obs.ReqClient(host=host, port=port, password=password)
+            event = obs.EventClient(host=host, port=port, password=password)
         except ConnectionRefusedError:
             logger.info("OBS WebSocket not ready, retrying...")
         except obs.events.OBSSDKError:
             raise RuntimeError("Check OBS credentials")
             
-        if con:
+        if req and event:
             logger.info(f"Successfully connected to OBS at {host}:{port}")
-            return con
+            return {
+                "req": req,
+                "event": event
+            }
 
         time.sleep(init_sleep)
         init_sleep *= 2
@@ -77,42 +79,37 @@ def cleanup_physical_files(directory: str, max_age_seconds: int) -> None:
                 os.remove(file_path)
                 logger.info(f"Removed old file: {file_path}")
 
-class Handler(FileSystemEventHandler):
-    def on_created(self, event):
-        if event.is_directory:
-            return
-        if not event.src_path.endswith(".ts"):
-            return
-
-        add_file_to_state(event.src_path)
+def on_record_file_changed(event) -> None:
+    new_file = event.new_output_path
+    add_file_to_state(new_file)
 
 def main() -> None:
     config = Config()
-    con = open_obs_connection(config.obs_host, config.obs_port, config.obs_password, OBS_MAX_RETRIES)
+    obs_host = config.get_obs_host()
+    obs_port = config.get_obs_port()
+    obs_password = config.get_obs_password()
 
-    recording_dir = con.get_record_directory().record_directory
-    start_recording(con)
+    connections = open_obs_connection(obs_host, obs_port, obs_password, OBS_MAX_RETRIES)
+    req_con = connections["req"]
+    event_con = connections["event"]
+
+    event_con.callback.register(on_record_file_changed)
+
+    recording_dir = req_con.get_record_directory().record_directory
+    start_recording(req_con)
 
     create_state_file_if_needed()
     create_initial_marker()
 
     try:
-        event_handler = Handler()
-        observer = Observer()
-        observer.schedule(event_handler, path=recording_dir, recursive=False)
-        observer.start()
-
         while running:
-            cleanup_physical_files(recording_dir, config.max_record_time)
-            cleanup_state(config.max_record_time)
+            cleanup_physical_files(recording_dir, config.get_max_record_time())
+            cleanup_state(config.get_max_record_time())
             time.sleep(INTERVAL)
     finally:
-        if observer:
-            observer.stop()
-            observer.join()
-
-        stop_recording(con)
-        con.disconnect()
+        stop_recording(req_con)
+        event_con.disconnect()
+        req_con.disconnect()
         logger.info("Daemon stopped")
 
 if __name__ == "__main__":

rewind/media.py

@@ -0,0 +1,114 @@
+import os
+import subprocess
+import tempfile
+
+from rewind.state import load_state
+from tqdm import tqdm
+
+"""
+Retrieves .ts files recorded between the specified timestamps.
+Returns a list of file paths and extra start and end offsets if needed.
+get_duration() is used as little as possible since it is slow.
+end_timestamp of a file is the start time of the next file.
+"""
+def get_ts_files(
+        ts_files: list[dict],
+        start_timestamp: float, 
+        end_timestamp: float
+        ) -> tuple[list[str], float, float]:
+    selected_files = []
+    start_offset = 0.0
+    end_offset = 0.0
+
+    for i, file_info in enumerate(ts_files):
+        file_start = file_info["timestamp"]
+        file_end = ts_files[i + 1]["timestamp"] if i + 1 < len(ts_files) else get_duration(file_info["path"]) + file_start
+        
+        if file_end <= start_timestamp:
+            continue
+        if file_start >= end_timestamp:
+            break
+
+        selected_files.append(file_info["path"])
+
+        if file_start < start_timestamp:
+            start_offset = start_timestamp - file_start
+
+        if file_end >= end_timestamp:
+            end_offset = file_end - end_timestamp
+            break
+        
+    return selected_files, start_offset, end_offset
+
+def concat_ts_files(file_list: list[str], start_offset: float, end_offset: float, length: float, output_file: str) -> None:
+    tmp_file = tempfile.NamedTemporaryFile(mode="w", suffix=".txt", delete=False)
+    try:
+        for file_path in file_list:
+            tmp_file.write(f"file '{file_path}'\n")
+        tmp_file.close()
+
+        cmd = ["ffmpeg", "-y", "-hide_banner", "-loglevel", "error", "-nostats", "-progress", "pipe:1"]
+        if start_offset > 0:
+            cmd += ["-ss", str(start_offset)]
+        if end_offset > 0:
+            cmd += ["-t", str(length)]
+        cmd += ["-f", "concat", "-safe", "0", "-i", tmp_file.name, "-c", "copy"]
+        cmd.append(output_file)
+
+        process = subprocess.Popen(
+            cmd,
+            stdout=subprocess.PIPE,
+            stderr=subprocess.PIPE,
+            text=True,
+            bufsize=1,
+        )
+
+        init_ms_val = 0
+        init_ms_val_set = False
+
+        with tqdm(
+            total=length,
+            unit="s",
+            unit_scale=True,
+            unit_divisor=60,
+            desc="Processing",
+            leave=True,
+        ) as pbar:
+            for line in process.stdout:  # type: ignore[union-attr]
+                line = line.strip()
+
+                if line.startswith("out_time_ms="):
+                    out_time_ms = int(line.split("=")[1])
+
+                    if not init_ms_val_set:
+                        init_ms_val = out_time_ms
+                        init_ms_val_set = True
+                    out_time_ms -= init_ms_val
+
+                    seconds = abs(out_time_ms / 1_000_000)
+                    pbar.n = min(seconds, length)
+                    pbar.refresh()
+
+                elif line == "progress=end":
+                    break
+
+        ret = process.wait()
+        if ret != 0:
+            raise RuntimeError("ffmpeg failed")
+    finally:
+        os.unlink(tmp_file.name)
+
+def get_duration(file_path: str) -> float:
+    result = subprocess.run(
+        ["ffprobe", "-v", "error", "-show_entries",
+         "format=duration", "-of",
+         "default=noprint_wrappers=1:nokey=1", file_path],
+        stdout=subprocess.PIPE,
+        stderr=subprocess.PIPE,
+        text=True,
+    )
+
+    if result.returncode != 0:
+        raise RuntimeError(f"ffprobe failed for file {file_path}")
+
+    return float(result.stdout.strip())

rewind/os/backend.py

@@ -0,0 +1,15 @@
+class OSBackend:
+    def __init__(self, program_path: str):
+        self.program_path = program_path
+
+    def enable_autostart(self):
+        raise NotImplementedError("enable_autostart not implemented for this platform")
+
+    def disable_autostart(self):
+        raise NotImplementedError("disable_autostart not implemented for this platform")
+
+    def start_daemon(self):
+        raise NotImplementedError("start_daemon not implemented for this platform")
+
+    def stop_daemon(self):
+        raise NotImplementedError("stop_daemon not implemented for this platform")

rewind/os/linux.py

@@ -0,0 +1,80 @@
+import subprocess
+
+from pathlib import Path
+from rewind.os.backend import OSBackend
+
+class LinuxBackend(OSBackend):
+    def __init__(self, program_path: str):
+        super().__init__(program_path)
+
+    def _run(self, cmd: list[str]):
+        result = subprocess.run(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE, text=True)
+        if result.returncode != 0:
+            raise RuntimeError(f"Command failed: {' '.join(cmd)}\n{result.stderr}")
+        return result
+
+    def _create_systemd_service(self):
+        systemd_dir = Path.home() / ".config/systemd/user"
+        systemd_dir.mkdir(parents=True, exist_ok=True)
+
+        obs_service = systemd_dir / "obs.service"
+        daemon_service = systemd_dir / "rewind-daemon.service"
+
+        obs_service.write_text("""[Unit]
+    Description=OBS Studio
+    After=graphical-session.target
+    Wants=graphical-session.target
+
+    [Service]
+    # Ensure OBS sentinel files are cleaned up before starting the daemon
+    ExecStartPre=-/usr/bin/rm -rf %h/.config/obs-studio/.sentinel
+    ExecStart=obs --minimize-to-tray
+    Restart=on-failure
+    RestartSec=3
+
+    [Install]
+    WantedBy=default.target
+    """)
+
+        daemon_service.write_text(f"""[Unit]
+    Description=Rewind Daemon
+    After=obs.service
+    Requires=obs.service
+
+    [Service]
+    ExecStart={self.program_path}
+    Restart=always
+    RestartSec=5
+    Environment=PYTHONUNBUFFERED=1
+
+    [Install]
+    WantedBy=default.target
+    """)
+
+    def enable_autostart(self):
+        self._create_systemd_service()
+        self._run(["systemctl", "--user", "daemon-reload"])
+
+        self._run(["systemctl", "--user", "enable", "obs.service"])
+        self._run(["systemctl", "--user", "enable", "rewind-daemon.service"])
+
+        print("Installed OBS + rewind-daemon via systemd")
+
+    def disable_autostart(self):
+        self._create_systemd_service()
+        self._run(["systemctl", "--user", "disable", "rewind-daemon.service"])
+        self._run(["systemctl", "--user", "disable", "obs.service"])
+
+        systemd_dir = Path.home() / ".config/systemd/user"
+        (systemd_dir / "rewind-daemon.service").unlink(missing_ok=True)
+        (systemd_dir / "obs.service").unlink(missing_ok=True)
+        self._run(["systemctl", "--user", "daemon-reload"])
+
+    def start_daemon(self):
+        self._create_systemd_service()
+        self._run(["systemctl", "--user", "start", "rewind-daemon.service"])
+
+    def stop_daemon(self):
+        self._create_systemd_service()
+        self._run(["systemctl", "--user", "stop", "rewind-daemon.service"])
+        self._run(["systemctl", "--user", "stop", "obs.service"])

rewind/os/main.py

@@ -0,0 +1,37 @@
+#!/usr/bin/env python3
+import platform
+import shutil
+
+from rewind.os.linux import LinuxBackend
+
+APP_NAME = "rewind-daemon"
+
+def _find_executable():
+    path = shutil.which(APP_NAME)
+    if not path:
+        raise RuntimeError(f"{APP_NAME} not found in PATH")
+    return path
+
+def _get_backend():
+    system = platform.system()
+    program_path = _find_executable()
+    if system == "Linux":
+        return LinuxBackend(program_path)
+    else:
+        raise RuntimeError(f"Autostart on OS {system} not compatible or not implemented")
+
+def enable_autostart():
+    backend = _get_backend()
+    backend.enable_autostart()
+    
+def disable_autostart():
+    backend = _get_backend()
+    backend.disable_autostart()
+
+def start_daemon():
+    backend = _get_backend()
+    backend.start_daemon()
+    
+def stop_daemon():
+    backend = _get_backend()
+    backend.stop_daemon()

rewind/paths.py

@@ -1,15 +1,65 @@
 #!/usr/bin/env python3
 import os
+import platform
 from pathlib import Path
 
 APP_NAME = "rewind"
 
-def get_config_dir() -> Path:
-    base = os.environ.get("XDG_CONFIG_HOME", Path.home() / ".config")
-    return Path(base) / APP_NAME
+def _create_dirs(path: Path) -> None:
+    if not path.exists():
+        path.mkdir(parents=True, exist_ok=True)
 
+"""
+Returns the path to the directory where config files should be stored, creating it if it doesn't exist.
+The location is determined based on the operating system:
+- Linux: Uses XDG_CONFIG_HOME environment variable or defaults to ~/.config/rewind
+- macOS: Uses ~/Library/Application Support/rewind
+- Windows: Uses APPDATA environment variable or defaults to %APPDATA%\rewind
+"""
+def get_config_dir() -> Path:
+    system = platform.system()
+    home = Path.home()
+
+    if system == "Linux":
+        base = os.environ.get("XDG_CONFIG_HOME", home / ".config")
+        path = Path(base) / APP_NAME
+        _create_dirs(path)
+        return path
+    elif system == "Darwin":
+        path = home / "Library" / "Application Support" / APP_NAME
+        _create_dirs(path)
+        return path
+    elif system == "Windows":
+        path = Path(os.environ.get("APPDATA", home / "AppData" / "Roaming")) / APP_NAME
+        _create_dirs(path)
+        return path
+    else:
+        raise OSError("Unsupported operating system")
+
+"""
+Returns the path to the directory where state files should be stored, creating it if it doesn't exist.
+The location is determined based on the operating system:
+- Linux: Uses XDG_STATE_HOME environment variable or defaults to ~/.local/state/rewind
+- macOS: Uses ~/Library/Application Support/rewind/state
+- Windows: Uses LOCALAPPDATA environment variable or defaults to %LOCALAPPDATA%\rewind\state
+"""
 def get_state_dir() -> Path:
-    base = os.path.expanduser("~/.local/share")
-    path = Path(base) / APP_NAME
-    path.mkdir(parents=True, exist_ok=True)
-    return path
+    system = platform.system()
+    home = Path.home()
+
+    if system == "Linux":
+        base = os.environ.get("XDG_STATE_HOME", home / ".local" / "state")
+        path = Path(base) / APP_NAME
+        _create_dirs(path)
+        return path
+    elif system == "Darwin":
+        path = home / "Library" / "Application Support" / APP_NAME / "state"
+        _create_dirs(path)
+        return path
+    elif system == "Windows":
+        base = Path(os.environ.get("LOCALAPPDATA", home / "AppData" / "Local"))
+        path = base / APP_NAME / "state"
+        _create_dirs(path)
+        return path
+    else:
+        raise OSError("Unsupported operating system")

rewind/state.py

@@ -21,7 +21,7 @@ def get_state_file_path() -> Path:
 def load_state() -> dict:
     path = get_state_file_path()
     if not path.exists():
-        return EMPTY_STATE.copy()
+        return {"files": [], "markers": []}
 
     with path.open() as f:
         return json.load(f)
@@ -37,7 +37,7 @@ def write_state(state: dict) -> None:
 
 def add_file_to_state(file_path: str) -> None:
     state = load_state()
-    files = state.get("files", [])
+    files = sorted(state.get("files", []), key=lambda f: f["timestamp"])
 
     # Idempotency guard
     existing_paths = {f["path"] for f in files}
@@ -46,7 +46,7 @@ def add_file_to_state(file_path: str) -> None:
 
     files.append({
         "path": file_path,
-        "timestamp": datetime.datetime.now().timestamp(),
+        "timestamp": datetime.datetime.now().timestamp()
     })
 
     state["files"] = files