# Copyright (c) 2022 Contrast Security, Inc. See https://www.contrastsecurity.com/enduser-terms-0317a for more details.
# frozen_string_literal: true

require 'contrast/utils/object_share'

module Contrast
  module Agent
    module Assess
      module Policy
        # This is how we scan our customer's code. It provides a way to analyze
        # the classes we need to observe to find vulnerabilities in the context
        # of a file vs data flow, such as the detection of Hardcoded Passwords
        # or Keys.
        module PolicyScanner
          class << self
            # Use the given trace_point, built from an :end event, to determine
            # where the loaded code lives and scan that code for policy
            # violations.
            #
            # @param trace_point [TracePoint] the TracePoint generated by an
            #   :end event at the end of a Module definition.
            def scan trace_point
              return unless ::Contrast::ASSESS.enabled?
              return unless ::Contrast::ASSESS.require_scan?

              provider_values = policy.providers.values
              return if provider_values.all?(&:disabled?)

              return unless trace_point.path
              return if trace_point.path.start_with?(Gem.dir)

              mod = trace_point.self
              return if mod.cs__frozen? || mod.singleton_class?

              different_ruby_version trace_point, provider_values, mod
            end

            def different_ruby_version trace_point, provider_values, mod
              # TODO: RUBY-1014 - remove non-AST approach
              if RUBY_VERSION >= '2.6.0'
                # TODO: RUBY-714 EOL 2.5. That check will be removed and the code will be brought back in here.
                ast = RubyVM::AbstractSyntaxTree.parse_file(trace_point.path)
                provider_values.each do |provider|
                  provider.parse(trace_point, ast)
                end
              else
                provider_values.each do |provider|
                  provider.analyze(mod)
                end
              end
            end

            def policy
              Contrast::Agent::Assess::Policy::Policy.instance
            end
          end
        end
      end
    end
  end
end