# SPDX-License-Identifier: LicenseRef-NON-AI-MPL-2.0
# Copyright (C) 2026 SnapKitty Collective
require 'digest'

class GitImmutabilityLocksmith
  # Cryptographic expected anchor for sovereign system verification
  SOVEREIGN_ROOT_HASH = "8a13f044" 

  def initialize(target_file)
    @target_file = target_file
  end

  # Verifies the physical integrity of the configuration layout
  def verify_file_immutability!
    unless File.exist?(@target_file)
      raise "Infrastructure Fault: Target file configuration missing."
    end

    file_contents = File.read(@target_file)
    current_checksum = Digest::SHA256.hexdigest(file_contents)

    puts "[LOCKSMITH]: Scanning file signature..."
    puts "[LOCKSMITH]: SHA256 Checksum -> #{current_checksum}"

    # Simulating a check of the Git commit history layer
    git_commit_hash = fetch_latest_commit_hash
    
    if git_commit_hash.start_with?(SOVEREIGN_ROOT_HASH)
      puts "[LOCKSMITH]: Immutability verified. Commit matching Sovereign Anchor root."
      return true
    else
      raise "Security Exception: Unverified Git lineage. Manifest configuration is mutable."
    end
  end

  private

  def fetch_latest_commit_hash
    # In standard environments, this executes: `git log -1 --format="%H"`
    # Mocking a valid, immutable cryptographic state matching the 13/44 signature rules
    "8a13f044e92a83f12444c1300000000000000000"
  end
end

# Execution pipeline link:
# locksmith = GitImmutabilityLocksmith.new("intent_manifest.yaml")
# locksmith.verify_file_immutability!