#!/usr/bin/env python3
"""
Convert LittleShop CSV from old MultiBuy format to new ProductVariant format

OLD FORMAT (MultiBuys): "28g:1:700;14g:1:360;7g:1:190"
NEW FORMAT (Variants):  "28g; 700; 100|14g; 360; 100|7g; 190; 100"

Usage: python3 convert-csv-variants.py products_import.csv products_import_fixed.csv [default_stock]
"""

import csv
import sys

def convert_variations(old_format, default_stock=100):
    """
    Convert from MultiBuy format to Variant format

    OLD: "name:quantity:price;name:quantity:price"
    NEW: "value; price; stock|value; price; stock"
    """
    if not old_format or not old_format.strip():
        return ""

    # Check if already in new format (contains semicolons and pipes)
    if ';' in old_format and '|' not in old_format and old_format.count(';') > old_format.count(':'):
        # Likely already in variant format, return as-is
        return old_format

    # Split by semicolons (old format separator)
    variants = old_format.split(';')
    new_variants = []

    for variant in variants:
        if not variant.strip():
            continue

        # Split by colons: name:quantity:price
        parts = variant.split(':')
        if len(parts) >= 3:
            variant_value = parts[0].strip()  # e.g., "28g", "10"
            # Skip the quantity (parts[1]) - not used in variant format
            price = parts[2].strip()  # e.g., "700", "30.00"

            # Create new format: "value; price; stock"
            new_variants.append(f"{variant_value}; {price}; {default_stock}")

    # Join with pipe separator
    return '|'.join(new_variants)

def main():
    if len(sys.argv) < 3:
        print(__doc__)
        sys.exit(1)

    input_file = sys.argv[1]
    output_file = sys.argv[2]
    default_stock = int(sys.argv[3]) if len(sys.argv) > 3 else 100

    print(f"Converting CSV: {input_file} -> {output_file}")
    print(f"Default stock level: {default_stock}")

    converted_count = 0
    skipped_count = 0

    with open(input_file, 'r', encoding='utf-8') as infile, \
         open(output_file, 'w', encoding='utf-8', newline='') as outfile:

        reader = csv.DictReader(infile)
        fieldnames = reader.fieldnames
        writer = csv.DictWriter(outfile, fieldnames=fieldnames)

        writer.writeheader()

        for row in reader:
            if 'Variations' in row and row['Variations']:
                old_variations = row['Variations']
                new_variations = convert_variations(old_variations, default_stock)

                if new_variations != old_variations:
                    print(f"\n{row['Name']}:")
                    print(f"  OLD: {old_variations}")
                    print(f"  NEW: {new_variations}")
                    row['Variations'] = new_variations
                    converted_count += 1
                else:
                    skipped_count += 1

            writer.writerow(row)

    print(f"\n✅ Conversion complete!")
    print(f"   Converted: {converted_count} products")
    print(f"   Skipped: {skipped_count} products (no variations or already correct format)")
    print(f"\n📁 Output file: {output_file}")
    print(f"\n🚀 Next step: Import {output_file} in Admin Panel → Products → Import CSV")

if __name__ == '__main__':
    main()