#!/usr/bin/env python3
"""JSON Validator CLI - Validates JSON files and reports syntax errors."""
import json
import sys
from pathlib import Path


def validate_json_file(filepath: str) -> dict:
    """Validate a JSON file and return result dict."""
    result = {
        "file": filepath,
        "valid": False,
        "error": None,
        "line": None,
        "column": None,
        "decoded": None
    }
    
    try:
        content = Path(filepath).read_text()
    except FileNotFoundError:
        result["error"] = f"File not found: {filepath}"
        return result
    except Exception as e:
        result["error"] = f"Read error: {e}"
        return result
    
    try:
        data = json.loads(content)
        result["valid"] = True
        result["decoded"] = data
        return result
    except json.JSONDecodeError as e:
        result["error"] = str(e.msg)
        result["line"] = e.lineno
        result["column"] = e.colno
        # Show context around error
        lines = content.split('\n')
        if e.lineno and e.lineno <= len(lines):
            result["context"] = lines[e.lineno - 1]
        return result


def main():
    if len(sys.argv) < 2:
        print("Usage: json_validate_standalone.py <file.json> [file2.json...]")
        sys.exit(1)
    
    exit_code = 0
    results = []
    
    for filepath in sys.argv[1:]:
        result = validate_json_file(filepath)
        results.append(result)
        
        if result["valid"]:
            print(f"VALID: {filepath}")
        else:
            print(f"INVALID: {filepath}")
            print(f"  Error: {result['error']}")
            if result.get('line'):
                print(f"  Line: {result['line']}, Column: {result['column']}")
                if result.get('context'):
                    print(f"  Context: {result['context'][:60]}")
            exit_code = 1
    
    sys.exit(exit_code)


if __name__ == "__main__":
    main()