#!/usr/bin/env python3
"""
JSON Validator - Validates JSON files with detailed error reporting.
Usage: python3 json_validator.py <file.json> [file2.json ...]
"""
import json
import sys
from pathlib import Path
from typing import Any


def validate_json_file(filepath: str) -> dict[str, Any]:
    """Validate a JSON file and return analysis results."""
    result = {
        "file": filepath,
        "valid": False,
        "error": None,
        "type": None,
        "size": None,
        "line_count": None,
        "structure": None
    }
    
    path = Path(filepath)
    if not path.exists():
        result["error"] = f"File not found: {filepath}"
        return result
    
    result["size"] = path.stat().st_size
    
    try:
        with open(path, 'r', encoding='utf-8') as f:
            content = f.read()
            result["line_count"] = content.count('\n') + 1
        
        data = json.loads(content)
        result["valid"] = True
        result["type"] = type(data).__name__
        
        if isinstance(data, dict):
            result["structure"] = f"Object with {len(data)} keys"
        elif isinstance(data, list):
            result["structure"] = f"Array with {len(data)} elements"
        else:
            result["structure"] = f"Scalar value: {type(data).__name__}"
            
    except json.JSONDecodeError as e:
        result["error"] = f"Line {e.lineno}, Column {e.colno}: {e.msg}"
    except UnicodeDecodeError as e:
        result["error"] = f"Encoding error: {e.reason}"
    except Exception as e:
        result["error"] = f"Unexpected error: {e}"
    
    return result


def main():
    if len(sys.argv) < 2:
        print("Usage: python3 json_validator.py <file.json> [file2.json ...]")
        print("\nValidates JSON files with detailed error reporting.")
        sys.exit(1)
    
    files = sys.argv[1:]
    results = [validate_json_file(f) for f in files]
    
    for r in results:
        status = "✓ VALID" if r["valid"] else "✗ INVALID"
        print(f"\n{status}: {r['file']}")
        
        if r["valid"]:
            print(f"  Type: {r['type']}")
            print(f"  Structure: {r['structure']}")
            print(f"  Size: {r['size']} bytes, {r['line_count']} lines")
        else:
            print(f"  Error: {r['error']}")
    
    # Exit with error code if any file is invalid
    sys.exit(0 if all(r["valid"] for r in results) else 1)


if __name__ == "__main__":
    main()