how can I know if the second if is or is not under the first if condition ?

(I am using crystal language)

# A simple evaluator for your package info file
class PackageApiEvaluator
  # @condition_stack tracks the "truthiness" of the current block.
  # We start with [true] for the global scope.
  def initialize
    @condition_stack = [true]
  end

  # Returns true if the *current* block we are in is active.
  def active? : Bool
    @condition_stack.last
  end

  # Main processing loop
  def evaluate_file(path : String)
    File.each_line(path) do |line|
      process_line(line.strip)
    end

    # After the file, the stack should only have the global scope left
    if @condition_stack.size != 1
      raise "Mismatched 'if'/'endif' blocks. Stack is not balanced."
    end
  end

  def process_line(line : String)
    return if line.empty?

    if line.starts_with?("if ")
      # --- Handle IF ---
      condition_string = line[3..]
      
      if active?
        # We are in an active block, so we must evaluate
        is_true = evaluate_condition(condition_string)
        @condition_stack.push(is_true)
      else
        # We are already in a "false" block.
        # This new 'if' is automatically skipped.
        # Push 'false' to maintain stack balance.
        @condition_stack.push(false)
      end

    elsif line == "endif"
      # --- Handle ENDIF ---
      if @condition_stack.size <= 1
        raise "Unexpected 'endif' without a matching 'if'"
      end
      @condition_stack.pop

    else
      # --- Handle a normal statement ---
      # Only execute if our current stack state is active
      if active?
        execute_statement(line)
      end
    end
  end

  # This is where you would put your real logic
  def evaluate_condition(condition : String) : Bool
    puts "  (Evaluating condition: '#{condition}')"
    # Example logic:
    case condition
    when "arch == x86_64"
      # Replace with `host_cpu.includes?("x86_64")` or similar
      return true 
    when "distro == fedora"
      return false # Dummy value
    else
      return true # Default
    end
  end

  # This is where you would call your API functions
  def execute_statement(statement : String)
    puts "Executing: #{statement}"
    # Example:
    # if statement.starts_with?("Dependency")
    #   add_dependency(statement[11..].strip)
    # end
  end
end

# --- Example Usage ---
# Create a dummy file for the test
File.write("package.info", <<-FILE
Name "MyPackage"
Version "1.0"

if arch == x86_64
  Source "source-x64.tar.gz"
  if distro == fedora
    Dependency "lib-fedora.so"
  endif
  Dependency "common-x64.so"
endif

if distro == ubuntu
  Dependency "lib-ubuntu.so"
endif

Description "A test package"
FILE
)

puts "--- Starting Evaluator ---"
evaluator = PackageApiEvaluator.new
evaluator.evaluate_file("package.info")
puts "--- Evaluator Finished ---"