import argparse

from datetime import datetime, timedelta

def mirror_dates(source_data, staging_data, date_field, days_back=7, dry_run=False):

"""Mirrors date values from source to staging data."""

try:

source_dates = source_data[date_field]

staging_dates = staging_data[date_field]

except KeyError as e:

raise ValueError(f"Date field '{date_field}' not found in source or staging data.")

cutoff_date = datetime.now() - timedelta(days=days_back)

for i in range(len(source_dates)):

source_date = source_dates[i]

# Only mirror if the source date is within the cutoff

if source_date >= cutoff_date:

try:

staging_dates[i] = source_date # Mirror the date

except TypeError:

print(f"Warning: Could not mirror date. Type mismatch. Source: {source_date}, Staging: {staging_dates[i]}. Skipping.")

continue #skip to next iteration

if not dry_run:

staging_data[date_field] = source_dates[source_dates >= cutoff_date] # overwrite with source data

else:

print("Dry run: No changes made.")

def main():

parser = argparse.ArgumentParser(description="Mirror date values from source to staging.")

parser.add_argument("source_file", help="Path to the source data file.")

parser.add_argument("staging_file", help="Path to the staging data file.")

parser.add_argument("date_field", help="Name of the date field.")

parser.add_argument("--days_back", type=int, default=7, help="Number of days to go back for mirroring (default: 7).")

parser.add_argument("--dry_run", action="store_true", help="Perform a dry run (no changes made).")

args = parser.parse_args()

try:

# Simulate reading data from files (replace with actual file reading logic)

source_data = {"dates": [datetime.now() - timedelta(days=i) for i in range(15)]}

staging_data = {"dates": [datetime.now() - timedelta(days=i) for i in range(15)]}

mirror_dates(source_data, staging_data, args.date_field, args.days_back, args.dry_run)

# Simulate writing back to files (replace with actual file writing logic)

print("Mirroring complete.")

except ValueError as e:

print(f"Error: {e}")

except Exception as e:

print(f"An unexpected error occurred: {e}")

if __name__ == "__main__":

main()