#!/usr/bin/env python3
"""
Self-validating checksum script.
Verifies its own SHA256 hash matches EXPECTED_HASH constant.
The hash excludes the EXPECTED_HASH line (lines 11-12) for self-consistency.
"""

import hashlib
import sys
from pathlib import Path

EXPECTED_HASH = "a80cd19cb447c3f7183965bc9055cb160daf9411f598fd8028dc95cbadf33f15"

def compute_self_hash():
    """Compute SHA256 hash excluding the EXPECTED_HASH value line."""
    script_path = Path(__file__).resolve()
    lines = script_path.read_text().split('\n')
    # Exclude lines 11-12 (0-indexed: 10-11) which contain EXPECTED_HASH
    relevant_lines = lines[:10] + lines[12:]
    relevant_content = '\n'.join(relevant_lines) + '\n'
    return hashlib.sha256(relevant_content.encode()).hexdigest()

def main():
    actual_hash = compute_self_hash()
    print(f"Computed hash: {actual_hash}")
    
    script_path = Path(__file__).resolve()
    content = script_path.read_text()
    
    # Extract current expected hash from file
    for line in content.split('\n'):
        if line.startswith('EXPECTED_HASH = '):
            expected = line.split('"')[1]
            break
    
    if actual_hash == expected:
        print("VERIFIED")
        return 0
    else:
        print(f"FAILED: expected {expected}")
        return 1

if __name__ == "__main__":
    sys.exit(main())