#!/usr/bin/env python3
"""Fix UTF-8 mojibake in JSON files."""

import json
import sys
from pathlib import Path

# Common mojibake patterns (UTF-8 bytes misinterpreted as Latin-1/Windows-1252)
MOJIBAKE_FIXES = {
    'â€"': '—',    # em dash
    'â€': '—',     # em dash (truncated)
    '’': "'",    # right single quote
    '“': '"',    # left double quote
    'â€': '"',     # right double quote
    '•': '•',    # bullet
    '…': '…',    # ellipsis
    'é': 'é',     # é
    'è': 'è',     # è
    'á': 'á',     # á
    'í': 'í',     # í
    'ó': 'ó',     # ó
    'ú': 'ú',     # ú
    'ñ': 'ñ',     # ñ
    'ü': 'ü',     # ü
    'ö': 'ö',     # ö
    'ä': 'ä',     # ä
    'ü': 'ü',     # ü
    'ö': 'ö',     # ö
    'ä': 'ä',     # ä
    'Â': '',       # stray  (common before accented chars)
}

def fix_mojibake(text: str) -> tuple[str, int]:
    """Fix common UTF-8 mojibake patterns. Returns (fixed_text, num_fixes)."""
    count = 0
    result = text
    for bad, good in MOJIBAKE_FIXES.items():
        before = result.count(bad)
        if before:
            result = result.replace(bad, good)
            count += before
    return result, count

def fix_json_file(path: Path, dry_run: bool = False) -> int:
    """Fix mojibake in a JSON file. Returns number of fixes applied."""
    try:
        with open(path, 'r', encoding='utf-8') as f:
            content = f.read()
    except UnicodeDecodeError as e:
        print(f"  [ERROR] {path}: Not valid UTF-8 at position {e.start}")
        return 0
    
    try:
        data = json.loads(content)
    except json.JSONDecodeError as e:
        print(f"  [ERROR] {path}: Invalid JSON at position {e.pos}")
        return 0
    
    # Recursively fix strings in JSON
    def fix_obj(obj):
        fixes = 0
        if isinstance(obj, str):
            fixed, count = fix_mojibake(obj)
            return fixed, count
        elif isinstance(obj, dict):
            new_dict = {}
            for k, v in obj.items():
                fixed_k, c1 = fix_obj(k)
                fixed_v, c2 = fix_obj(v)
                fixes += c1 + c2
                new_dict[fixed_k] = fixed_v
            return new_dict, fixes
        elif isinstance(obj, list):
            new_list = []
            for item in obj:
                fixed, count = fix_obj(item)
                fixes += count
                new_list.append(fixed)
            return new_list, fixes
        else:
            return obj, 0
    
    fixed_data, fix_count = fix_obj(json.loads(json.dumps(data)))  # Round-trip to ensure clean JSON
    
    if fix_count > 0 and not dry_run:
        with open(path, 'w', encoding='utf-8') as f:
            json.dump(fixed_data, f, ensure_ascii=False, indent=1)
        print(f"  Fixed {fix_count} mojibake in {path}")
    
    return fix_count

def main():
    import argparse
    parser = argparse.ArgumentParser(description="Fix UTF-8 mojibake in JSON files")
    parser.add_argument('path', nargs='?', default='.', help='Root directory to scan')
    parser.add_argument('--dry-run', action='store_true', help='Show what would be fixed')
    args = parser.parse_args()
    
    root = Path('.').resolve()
    print(f"Scanning {Path('.').resolve()} for JSON files...")
    
    total_fixes = 0
    files_fixed = 0
    
    for path in Path('.').rglob("*.json"):
        if any(part.startswith('.') for part in path.parts):
            continue
        if path.name.startswith('.'):
            continue
            
        fixes = fix_json_file(path, dry_run=args.dry_run)
        if fixes > 0:
            files_fixed += 1
            print(f"  Fixed {fixes} issues in {path}")
    
    print(f"\nDone. Fixed {files_fixed} files.")

if __name__ == '__main__':
    main()