# frozen_string_literal: true

require "optparse"

module SlimLint
  # Handles option parsing for the command line application.
  class Options
    # Parses command line options into an options hash.
    #
    # @param args [Array<String>] arguments passed via the command line
    # @return [Hash] parsed options
    def parse(args)
      @options = {}

      OptionParser.new do |parser|
        parser.banner = "Usage: #{APP_NAME} [options] [file1, file2, ...]"

        add_linter_options parser
        add_file_options parser
        add_info_options parser
      end.parse!(args)

      # Any remaining arguments are assumed to be files
      @options[:files] = args

      @options
    rescue OptionParser::InvalidOption => e
      raise Exceptions::InvalidCLIOption,
        e.message,
        e.backtrace
    end

    private

    # Register linter-related flags.
    def add_linter_options(parser)
      msg = "Specify which linters you want to run"
      parser.on("-i", "--include-linter linter,...", Array, msg) do |linters|
        @options[:included_linters] = linters
      end

      msg = "Specify which linters you don't want to run"
      parser.on("-x", "--exclude-linter linter,...", Array, msg) do |linters|
        @options[:excluded_linters] = linters
      end

      msg = "Specify which reporter you want to use to generate the output"
      parser.on("-r", "--reporter reporter", String, msg) do |reporter|
        @options[:reporter] = load_reporter_class(reporter.capitalize)
      end
    end

    # Returns the class of the specified Reporter.
    #
    # @param reporter_name [String]
    # @raise [SlimLint::Exceptions::InvalidCLIOption] if reporter doesn't exist
    # @return [Class]
    def load_reporter_class(reporter_name)
      SlimLint::Reporter.const_get("#{reporter_name}Reporter")
    rescue NameError
      raise SlimLint::Exceptions::InvalidCLIOption,
        "#{reporter_name}Reporter does not exist"
    end

    # Register file-related flags.
    def add_file_options(parser)
      msg = "Specify which configuration file you want to use"
      parser.on("-c", "--config config-file", String, msg) do |conf_file|
        @options[:config_file] = conf_file
      end

      msg = "List of file names to exclude"
      parser.on("-e", "--exclude file,...", Array, msg) do |files|
        @options[:excluded_files] = files
      end

      msg = "Pipe source from STDIN, using file in offense reports."
      parser.on("--stdin-file-path file", String, msg) do |file|
        @options[:stdin_file_path] = file
      end
    end

    # Register informational flags.
    def add_info_options(parser)
      parser.on("--show-linters", "Display available linters") do
        @options[:show_linters] = true
      end

      parser.on("--show-reporters", "Display available reporters") do
        @options[:show_reporters] = true
      end

      parser.on("--[no-]color", "Force output to be colorized") do |color|
        @options[:color] = color
      end

      parser.on_tail("-h", "--help", "Display help documentation") do
        @options[:help] = parser.help
      end

      parser.on_tail("-v", "--version", "Display version") do
        @options[:version] = true
      end

      parser.on_tail("-V", "--verbose-version", "Display verbose version information") do
        @options[:verbose_version] = true
      end
    end
  end
end