#!/usr/bin/env python3
"""
Migration script to convert wardrobe structure from flat to nested format.

Before:
  "wardrobe": {
    "headwear": "...",
    "top": "...",
    ...
  }

After:
  "wardrobe": {
    "default": {
      "headwear": "...",
      "top": "...",
      ...
    }
  }

This enables multiple outfits per character.
"""

import os
import json
from pathlib import Path


def migrate_wardrobe(characters_dir: str = "characters", dry_run: bool = False):
    """
    Migrate all character JSON files to the new wardrobe structure.
    
    Args:
        characters_dir: Path to the directory containing character JSON files
        dry_run: If True, only print what would be changed without modifying files
    """
    characters_path = Path(characters_dir)
    
    if not characters_path.exists():
        print(f"Error: Directory '{characters_dir}' does not exist")
        return
    
    json_files = list(characters_path.glob("*.json"))
    
    if not json_files:
        print(f"No JSON files found in '{characters_dir}'")
        return
    
    migrated_count = 0
    skipped_count = 0
    error_count = 0
    
    for json_file in json_files:
        try:
            with open(json_file, 'r', encoding='utf-8') as f:
                data = json.load(f)
            
            # Check if character has a wardrobe
            if 'wardrobe' not in data:
                print(f"  [SKIP] {json_file.name}: No wardrobe field")
                skipped_count += 1
                continue
            
            wardrobe = data['wardrobe']
            
            # Check if already migrated (wardrobe contains 'default' key with nested dict)
            if 'default' in wardrobe and isinstance(wardrobe['default'], dict):
                # Verify it's actually the new format (has wardrobe keys inside)
                expected_keys = {'headwear', 'top', 'legwear', 'footwear', 'hands', 'accessories', 
                                'inner_layer', 'outer_layer', 'lower_body', 'gloves'}
                if any(key in wardrobe['default'] for key in expected_keys):
                    print(f"  [SKIP] {json_file.name}: Already migrated")
                    skipped_count += 1
                    continue
            
            # Check if wardrobe is a flat structure (not already nested)
            # A flat wardrobe has string values, a nested one has dict values
            if not isinstance(wardrobe, dict):
                print(f"  [ERROR] {json_file.name}: Wardrobe is not a dictionary")
                error_count += 1
                continue
            
            # Check if any value is a dict (indicating partial migration or different structure)
            has_nested_values = any(isinstance(v, dict) for v in wardrobe.values())
            if has_nested_values:
                print(f"  [SKIP] {json_file.name}: Wardrobe has nested values, may already be migrated")
                skipped_count += 1
                continue
            
            # Perform migration
            new_wardrobe = {
                "default": wardrobe
            }
            data['wardrobe'] = new_wardrobe
            
            if dry_run:
                print(f"  [DRY-RUN] {json_file.name}: Would migrate wardrobe")
                print(f"            Old: {json.dumps(wardrobe, indent=2)[:100]}...")
                print(f"            New: {json.dumps(new_wardrobe, indent=2)[:100]}...")
            else:
                with open(json_file, 'w', encoding='utf-8') as f:
                    json.dump(data, f, indent=2, ensure_ascii=False)
                print(f"  [MIGRATED] {json_file.name}")
            
            migrated_count += 1
            
        except json.JSONDecodeError as e:
            print(f"  [ERROR] {json_file.name}: Invalid JSON - {e}")
            error_count += 1
        except Exception as e:
            print(f"  [ERROR] {json_file.name}: {e}")
            error_count += 1
    
    print()
    print("=" * 50)
    print(f"Migration complete:")
    print(f"  - Migrated: {migrated_count}")
    print(f"  - Skipped:  {skipped_count}")
    print(f"  - Errors:   {error_count}")
    if dry_run:
        print()
        print("This was a dry run. No files were modified.")
        print("Run with --execute to apply changes.")


if __name__ == "__main__":
    import argparse
    
    parser = argparse.ArgumentParser(
        description="Migrate character wardrobe structure to support multiple outfits"
    )
    parser.add_argument(
        "--execute",
        action="store_true",
        help="Actually modify files (default is dry-run)"
    )
    parser.add_argument(
        "--dir",
        default="characters",
        help="Directory containing character JSON files (default: characters)"
    )
    
    args = parser.parse_args()
    
    print("=" * 50)
    print("Wardrobe Migration Script")
    print("=" * 50)
    print(f"Directory: {args.dir}")
    print(f"Mode: {'EXECUTE' if args.execute else 'DRY-RUN'}")
    print("=" * 50)
    print()
    
    migrate_wardrobe(characters_dir=args.dir, dry_run=not args.execute)