fix(core): no existence validation of ts files

Now uses temp file module to prevent race conditions.

rewind/core.py

@@ -2,6 +2,7 @@
 import os
 import datetime
 import subprocess
+import tempfile
 
 from rewind.state import load_state, add_marker_to_state, remove_marker_from_state
 from rewind.config import Config
@@ -96,7 +97,7 @@ 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"]
+    ts_files = [f for f in load_state()["files"] if os.path.exists(f["path"])]
     selected_files = []
     start_offset = 0.0
     end_offset = 0.0
@@ -120,16 +121,18 @@ def _get_ts_files(start_timestamp: float, end_timestamp: float) -> tuple[list[st
     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:
+    tmp_file = tempfile.NamedTemporaryFile(mode="w", suffix=".txt", delete=False)
+    try:
         for file_path in file_list:
-            f.write(f"file '{file_path}'\n")
+            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", "file_list.txt", "-c", "copy"]
+        cmd += ["-f", "concat", "-safe", "0", "-i", tmp_file.name, "-c", "copy"]
         cmd.append(output_file)
 
         process = subprocess.Popen(
@@ -151,10 +154,9 @@ def _concat_ts_files(file_list: list[str], start_offset: float, end_offset: floa
             desc="Processing",
             leave=True,
         ) as pbar:
-        for line in process.stdout:
+            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])
 
@@ -171,10 +173,10 @@ def _concat_ts_files(file_list: list[str], start_offset: float, end_offset: floa
                     break
 
         ret = process.wait()
-    os.remove("file_list.txt")
-
         if ret != 0:
             raise RuntimeError("ffmpeg failed")
+    finally:
+        os.unlink(tmp_file.name)
 
 def get_duration(file_path: str) -> float:
     result = subprocess.run(
@@ -182,10 +184,11 @@ def get_duration(file_path: str) -> float:
          "format=duration", "-of",
          "default=noprint_wrappers=1:nokey=1", file_path],
         stdout=subprocess.PIPE,
-        stderr=subprocess.STDOUT
+        stderr=subprocess.PIPE,
+        text=True,
     )
 
     if result.returncode != 0:
         raise RuntimeError(f"ffprobe failed for file {file_path}")
 
-    return float(result.stdout)
+    return float(result.stdout.strip())

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)