ARB File Merger Tool

arb_merger.py

#!/usr/bin/env python3

"""
ARB File Merger Tool
===================

Merges multiple ARB files within a directory (recursive) into their respective
locale-specific `app_[locale].arb` files.

Usage:
    python arb_merger.py <directory>
"""

import json
import os
import sys
from pathlib import Path
from typing import Dict, Set

def load_arb_file(file_path: Path) -> Dict:
    """Load and parse an ARB file."""
    with open(file_path, 'r', encoding='utf-8') as f:
        return json.load(f)

def get_locale_from_filename(filename: str) -> str:
    """Extract locale from filename (e.g., 'something_en.arb' -> 'en')."""
    return filename.split('_')[-1].replace('.arb', '')

def find_arb_files(directory: Path) -> Dict[str, list[Path]]:
    """Find all ARB files and group them by locale."""
    arb_files: Dict[str, list[Path]] = {}

    for file_path in directory.rglob('*.arb'):
        if file_path.name.startswith('app_'):
            continue  # Skip main app ARB files

        locale = get_locale_from_filename(file_path.name)
        if locale not in arb_files:
            arb_files[locale] = []
        arb_files[locale].append(file_path)

    return arb_files

def merge_arb_files(files: list[Path]) -> Dict:
    """Merge multiple ARB files into one, checking for conflicts."""
    merged = {}
    conflicts: Dict[str, Set[str]] = {}

    for file_path in files:
        data = load_arb_file(file_path)
        for key, value in data.items():
            if key.startswith('@'):
                # Handle metadata
                if key not in merged:
                    merged[key] = value
                continue

            if key in merged:
                if key not in conflicts:
                    conflicts[key] = {str(file_path)}
                conflicts[key].add(str(file_path))
            merged[key] = value

            # Add metadata if exists
            metadata_key = f'@{key}'
            if metadata_key in data:
                merged[metadata_key] = data[metadata_key]

    # Report conflicts
    if conflicts:
        print("\nWarning: Found key conflicts:")
        for key, files in conflicts.items():
            print(f"Key '{key}' appears in multiple files:")
            for file in files:
                print(f"  - {file}")
        print("\nUsing last encountered value for each conflict.")

    return merged

def save_merged_arb(data: Dict, output_file: Path):
    """Save merged ARB data to a file."""
    with open(output_file, 'w', encoding='utf-8') as f:
        json.dump(data, f, indent=2, ensure_ascii=False)

def main():
    if len(sys.argv) != 2:
        print("Usage: python arb_merger.py <directory>")
        sys.exit(1)

    directory = Path(sys.argv[1])
    if not directory.exists():
        print(f"Error: Directory '{directory}' does not exist")
        sys.exit(1)

    print(f"Scanning directory: {directory}")
    arb_files = find_arb_files(directory)

    if not arb_files:
        print("No ARB files found to merge!")
        sys.exit(0)

    # Process each locale
    for locale, files in arb_files.items():
        print(f"\nProcessing {len(files)} files for locale '{locale}'...")

        # Define output file in the root of the l10n directory
        output_file = directory / f"app_{locale}.arb"

        if not files:
            print(f"No files to merge for locale '{locale}'")
            continue

        merged_data = merge_arb_files(files)

        # Add locale metadata if not present
        if "@@locale" not in merged_data:
            merged_data["@@locale"] = locale

        save_merged_arb(merged_data, output_file)
        print(f"Merged ARB saved to: {output_file}")

if __name__ == "__main__":
    main()