add automatic output filepath & force overwrite (-f) option

1 files changed, 40 insertions, 0 deletions

diff --git a/picostream/main.py b/picostream/main.py
index 8fc7f78..fb56d87 100644
--- a/picostream/main.py
+++ b/picostream/main.py
@@ -406,6 +406,30 @@ VOLTAGE_RANGE_MAP = {
 }
 
 
+def generate_unique_filename(base_path: str) -> str:
+    """Generate a unique filename by appending timestamp if file exists."""
+    import os
+    from pathlib import Path
+    
+    if not os.path.exists(base_path):
+        return base_path
+    
+    # Split the path into parts
+    path = Path(base_path)
+    stem = path.stem
+    suffix = path.suffix
+    parent = path.parent
+    
+    # Generate timestamp
+    timestamp = datetime.now().strftime("%Y%m%d_%H%M%S")
+    
+    # Create new filename with timestamp
+    new_filename = f"{stem}_{timestamp}{suffix}"
+    new_path = parent / new_filename
+    
+    return str(new_path)
+
+
 @click.command()
 @click.option(
     "--sample-rate",
@@ -483,6 +507,13 @@ VOLTAGE_RANGE_MAP = {
     type=float,
     help="Maximum buffer duration in seconds for live-only mode (limits file size).",
 )
+@click.option(
+    "--force",
+    "-f",
+    is_flag=True,
+    default=False,
+    help="Overwrite existing output file.",
+)
 def main(
     sample_rate: float,
     resolution: str,
@@ -496,6 +527,7 @@ def main(
     downsample_mode: str,
     offset: float,
     max_buff_sec: Optional[float],
+    force: bool,
 ) -> None:
     """High-speed data acquisition tool for Picoscope 5000a series."""
     # --- Argument Validation and Processing ---
@@ -526,6 +558,14 @@ def main(
     if not output:
         timestamp = datetime.now().strftime("%Y%m%d_%H%M%S")
         output = f"./output_{timestamp}.hdf5"
+    else:
+        # Check if file exists and handle accordingly
+        if not force:
+            original_output = output
+            output = generate_unique_filename(output)
+            if output != original_output:
+                logger.info(f"File '{original_output}' exists. Using '{output}' instead.")
+                logger.info("Use --force/-f to overwrite existing files.")
 
     logger.info(f"Output file: {output}")
     logger.info(f"Selected voltage range: {rangev}V -> {channel_range_str}")