#!/usr/bin/env ruby
# frozen_string_literal: true

#
# Wrapper for the CodeClimate integration.

require_relative '../lib/reek'
require_relative '../lib/reek/cli/application'
require_relative '../lib/reek/code_climate'
Reek::CLI::Silencer.silently { require 'parser/current' }

# Map input coming from CodeClimate to Reek.
class CodeClimateToReek
  # Following the spec (https://github.com/codeclimate/spec/blob/master/SPEC.md)
  # we have to exit with a zero for both failure and success.
  ENGINE_CONFIGURATION = [
    '--failure-exit-code', '0',
    '--success-exit-code', '0'
  ].freeze
  CUSTOM_CONFIG_KEY = 'config'
  CUSTOM_CONFIG_TARGET_RUBY_VERSION_KEY = 'target_ruby_version'

  attr_reader :configuration_file_path, :include_paths_key, :include_paths_default

  def initialize(configuration_file_path: '/config.json',
                 include_paths_key: 'include_paths',
                 include_paths_default: ['.'])
    @configuration_file_path = configuration_file_path
    @include_paths_key       = include_paths_key
    @include_paths_default   = include_paths_default
  end

  def cli_arguments
    include_paths + ENGINE_CONFIGURATION
  end

  def target_ruby_version
    config.dig(CUSTOM_CONFIG_KEY, CUSTOM_CONFIG_TARGET_RUBY_VERSION_KEY)
  end

  private

  def configuration_file_exists?
    Pathname.new(configuration_file_path).exist?
  end

  # The config.json file we try to read below might look like this:
  # {
  #   "include_paths":[
  #     "lib",
  #     "spec"
  #   ]
  # }
  def include_paths
    config.fetch include_paths_key, include_paths_default
  end

  def config
    if configuration_file_exists?
      JSON.parse File.read(configuration_file_path)
    else
      {}
    end
  end
end

# Override for ReportCommand to force the use of CodeClimateReport.
module ReportClassOverride
  def report_class
    Reek::CodeClimate::CodeClimateReport
  end
end

# Override Reek::Source::SourceCode to use a parser version specified by the user
module SourceCodeOverride
  # override self.default_parser method
  def default_parser
    parser_class.new(Reek::AST::Builder.new).tap do |parser|
      diagnostics = parser.diagnostics
      diagnostics.all_errors_are_fatal = true
      diagnostics.ignore_warnings      = true
    end
  end

  # config.json file will look like this:
  # {
  #   "include_paths":[
  #     "lib",
  #     "spec"
  #   ],
  #   "config": {
  #     "target_ruby_version": "3.1.0"
  #   }
  # }
  def parser_class
    # convert an X.Y.Z version number to an XY two digit number
    requested_version = CodeClimateToReek.new.target_ruby_version
    return Parser::CurrentRuby if requested_version.nil?

    version_number = Gem::Version.new(requested_version).segments[0..1].join

    begin
      Reek::CLI::Silencer.silently { require "parser/ruby#{version_number}" }
      Module.const_get("Parser::Ruby#{version_number}")
    rescue LoadError, NameError
      # use Parser::CurrentRuby when an invalid version number is provided
      Parser::CurrentRuby
    end
  end
end

Reek::CLI::Command::ReportCommand.prepend ReportClassOverride
Reek::Source::SourceCode.singleton_class.prepend SourceCodeOverride

application = Reek::CLI::Application.new(CodeClimateToReek.new.cli_arguments)

exit application.execute