# rubocop:disable  Metrics/ModuleLength

# == Annotate Routes
#
# Based on:
#
#
#
# Prepends the output of "rake routes" to the top of your routes.rb file.
# Yes, it's simple but I'm thick and often need a reminder of what my routes
# mean.
#
# Running this task will replace any existing route comment generated by the
# task. Best to back up your routes file before running:
#
# Author:
#  Gavin Montague
#  gavin@leftbrained.co.uk
#
# Released under the same license as Ruby. No Support. No Warranty.
#
module AnnotateRoutes
  PREFIX = '== Route Map'.freeze
  PREFIX_MD = '## Route Map'.freeze
  HEADER_ROW = ['Prefix', 'Verb', 'URI Pattern', 'Controller#Action']

  class << self
    def do_annotations(options = {})
      return unless routes_exists?
      existing_text = File.read(routes_file)

      if rewrite_contents_with_header(existing_text, header(options), options)
        puts "#{routes_file} annotated."
      end
    end

    def remove_annotations(_options={})
      return unless routes_exists?
      existing_text = File.read(routes_file)
      content, where_header_found = strip_annotations(existing_text)
      new_content = strip_on_removal(content, where_header_found)
      if rewrite_contents(existing_text, new_content)
        puts "Removed annotations from #{routes_file}."
      end
    end

    private

    def routes_exists?
      routes_exists = File.exists?(routes_file)
      puts "Can't find routes.rb" unless routes_exists

      routes_exists
    end

    def routes_file
      @routes_rb ||= File.join('config', 'routes.rb')
    end

    def rewrite_contents_with_header(existing_text, header, options = {})
      content, where_header_found = strip_annotations(existing_text)
      new_content = annotate_routes(header, content, where_header_found, options)

      # Make sure we end on a trailing newline.
      new_content << '' unless new_content.last == ''
      new_text = new_content.join("\n")

      if existing_text == new_text
        puts "#{routes_file} unchanged."
        false
      else
        File.open(routes_file, 'wb') { |f| f.puts(new_text) }
        true
      end
    end

    def header(options = {})
      routes_map = app_routes_map(options)

      magic_comments_map, routes_map = extract_magic_comments_from_array(routes_map)

      out = []

      magic_comments_map.each do |magic_comment|
        out << magic_comment
      end
      out << '' if magic_comments_map.any?

      out += ["# #{options[:wrapper_open]}"] if options[:wrapper_open]

      out += ["# #{options[:format_markdown] ? PREFIX_MD : PREFIX}" + (options[:timestamp] ? " (Updated #{Time.now.strftime('%Y-%m-%d %H:%M')})" : '')]
      out += ['#']
      return out if routes_map.size.zero?

      maxs = [HEADER_ROW.map(&:size)] + routes_map[1..-1].map { |line| line.split.map(&:size) }

      if options[:format_markdown]
        max = maxs.map(&:max).compact.max

        out += ["# #{content(HEADER_ROW, maxs, options)}"]
        out += ["# #{content(['-' * max, '-' * max, '-' * max, '-' * max], maxs, options)}"]
      else
        out += ["# #{content(routes_map[0], maxs, options)}"]
      end

      out += routes_map[1..-1].map { |line| "# #{content(options[:format_markdown] ? line.split(' ') : line, maxs, options)}" }
      out += ["# #{options[:wrapper_close]}"] if options[:wrapper_close]

      out
    end

    # TODO: write the method doc using ruby rdoc formats
    # where_header_found => This will either be :before, :after, or
    # a number.  If the number is > 0, the
    # annotation was found somewhere in the
    # middle of the file.  If the number is
    # zero, no annotation was found.
    def strip_annotations(content)
      real_content = []
      mode = :content
      header_found_at = 0

      content.split(/\n/, -1).each_with_index do |line, line_number|
        if mode == :header && line !~ /\s*#/
          mode = :content
          real_content << line unless line.blank?
        elsif mode == :content
          if line =~ /^\s*#\s*== Route.*$/
            header_found_at = line_number + 1 # index start's at 0
            mode = :header
          else
            real_content << line
          end
        end
      end

      where_header_found(real_content, header_found_at)
    end

    def strip_on_removal(content, where_header_found)
      if where_header_found == :before
        content.shift while content.first == ''
      elsif where_header_found == :after
        content.pop while content.last == ''
      end

      # TODO: If the user buried it in the middle, we should probably see about
      # TODO: preserving a single line of space between the content above and
      # TODO: below...
      content
    end

    # @param [String, Array<String>]
    def rewrite_contents(existing_text, new_content)
      # Make sure we end on a trailing newline.
      new_content << '' unless new_content.last == ''
      new_text = new_content.join("\n")

      if existing_text == new_text
        puts "#{routes_file} unchanged."
        false
      else
        File.open(routes_file, 'wb') { |f| f.puts(new_text) }
        true
      end
    end

    def annotate_routes(header, content, where_header_found, options = {})
      magic_comments_map, content = extract_magic_comments_from_array(content)
      if %w(before top).include?(options[:position_in_routes])
        header = header << '' if content.first != ''
        magic_comments_map << '' if magic_comments_map.any?
        new_content = magic_comments_map + header + content
      else
        # Ensure we have adequate trailing newlines at the end of the file to
        # ensure a blank line separating the content from the annotation.
        content << '' unless content.last == ''

        # We're moving something from the top of the file to the bottom, so ditch
        # the spacer we put in the first time around.
        content.shift if where_header_found == :before && content.first == ''

        new_content = magic_comments_map + content + header
      end

      new_content
    end

    def app_routes_map(options)
      routes_map = `rake routes`.chomp("\n").split(/\n/, -1)

      # In old versions of Rake, the first line of output was the cwd.  Not so
      # much in newer ones.  We ditch that line if it exists, and if not, we
      # keep the line around.
      routes_map.shift if routes_map.first =~ /^\(in \//

      # Skip routes which match given regex
      # Note: it matches the complete line (route_name, path, controller/action)
      if options[:ignore_routes]
        routes_map.reject! { |line| line =~ /#{options[:ignore_routes]}/ }
      end

      routes_map
    end

    # @param [Array<String>] content
    # @return [Array<String>] all found magic comments
    # @return [Array<String>] content without magic comments
    def extract_magic_comments_from_array(content_array)
      magic_comments = []
      new_content = []

      content_array.map do |row|
        if row =~ magic_comment_matcher
          magic_comments << row.strip
        else
          new_content << row
        end
      end

      [magic_comments, new_content]
    end

    def content(line, maxs, options = {})
      return line.rstrip unless options[:format_markdown]

      line.each_with_index.map do |elem, index|
        min_length = maxs.map { |arr| arr[index] }.max || 0

        sprintf("%-#{min_length}.#{min_length}s", elem.tr('|', '-'))
      end.join(' | ')
    end

    def where_header_found(real_content, header_found_at)
      # By default assume the annotation was found in the middle of the file

      # ... unless we have evidence it was at the beginning ...
      return real_content, :before if header_found_at == 1

      # ... or that it was at the end.
      return real_content, :after if header_found_at >= real_content.count

      # and the default
      return real_content, header_found_at
    end

    def magic_comment_matcher
      Regexp.new(/(^#\s*encoding:.*)|(^# coding:.*)|(^# -\*- coding:.*)|(^# -\*- encoding\s?:.*)|(^#\s*frozen_string_literal:.+)|(^# -\*- frozen_string_literal\s*:.+-\*-)/)
    end
  end
end