#!/usr/bin/env python3
"""Text file analyzer - counts lines, words, characters, bytes.
Usage: python3 file_analyzer.py <filepath>
Outputs JSON to stdout."""

import sys
import json
import os

def analyze_file(filepath):
    """Analyze a text file and return stats."""
    if not os.path.exists(filepath):
        return {"error": f"File not found: {filepath}"}
    
    if not os.path.isfile(filepath):
        return {"error": f"Not a file: {filepath}"}
    
    stats = {
        "path": os.path.abspath(filepath),
        "size_bytes": os.path.getsize(filepath),
    }
    
    try:
        with open(filepath, 'r', encoding='utf-8') as f:
            content = f.read()
    except Exception as e:
        return {"error": f"Cannot read file: {e}"}
    
    stats["size_chars"] = len(content)
    stats["lines"] = content.count('\n') + (1 if content and not content.endswith('\n') else 0)
    stats["words"] = len(content.split())
    stats["unique_chars"] = len(set(content))
    
    return stats

if __name__ == "__main__":
    if len(sys.argv) != 2:
        print(json.dumps({"error": "Usage: file_analyzer.py <filepath>"}))
        sys.exit(1)
    
    result = analyze_file(sys.argv[1])
    print(json.dumps(result, indent=2))
    
    if "error" in result:
        sys.exit(1)