#!/usr/bin/env ruby
# -*- coding: utf-8 -*-
#
#--
# Copyright (C) 2009-2019 Thomas Leitner <t_leitner@gmx.at>
#
# This file is part of kramdown which is licensed under the MIT.
#++
#

require 'optparse'
require 'rbconfig'
require 'yaml'
require 'kramdown'

def add_kramdown_options(opts, parsed_options, banner: [], ignore: [])
  banner_shown = false
  defined_options = []
  Kramdown::Options.definitions.sort.each do |n, definition|
    next if ignore.include?(n)

    unless banner_shown
      opts.separator("")
      banner.each {|part| opts.separator(part) }
      opts.separator("")
      banner_shown = true
    end

    defined_options << n
    no = n.to_s.tr('_', '-')
    if definition.type == Kramdown::Options::Boolean
      opts.on("--[no-]#{no}") {|v| parsed_options[n] = Kramdown::Options.parse(n, v) }
    else
      type = definition.type
      type = String if type == Symbol || type == Object
      opts.on("--#{no} ARG", type) {|v| parsed_options[n] = Kramdown::Options.parse(n, v) }
    end

    definition.desc.split(/\n/).each do |line|
      opts.separator opts.summary_indent + ' ' * 6 + line
    end
    opts.separator ''
  end
  defined_options
end

config_file = nil
begin
  config_dir = case RbConfig::CONFIG['host_os']
               when /bccwin|cygwin|djgpp|mingw|mswin|wince/i
                 File.expand_path((ENV['HOME'] || ENV['USERPROFILE'] || "~") + "/AppData/Local")
               when /darwin|mac os/
                 File.expand_path("~/Library/Preferences/")
               else
                 File.expand_path(ENV['XDG_CONFIG_HOME'] || '~/.config')
               end
  config_file = File.join(config_dir, "kramdownrc")
rescue StandardError
end

options = {}
format = ['html']

defined_options = []
OptionParser.new do |opts|
  opts.banner = "Usage: kramdown [options] [FILE FILE ...]"
  opts.summary_indent = ' ' * 4

  opts.separator ""
  opts.separator "Command line options:"
  opts.separator ""

  opts.on("-i", "--input ARG", "Specify the input format: kramdown (default), " \
          "html, or markdown") {|v| options[:input] = v }
  opts.on("-o", "--output ARG", Array, "Specify one or more output formats separated by commas: " \
          "html (default),", "kramdown, latex, man or remove_html_tags") {|v| format = v }
  opts.on("-x", "--extension EXT", Array, "Load one or more extensions (without the 'kramdown-' " \
          "prefix) separated", "by commas (e.g. parser-gfm,syntax-coderay)",
          "Note: Use this option before other options!") do |exts|
    exts.each do |ext|
      begin
        require "kramdown-#{ext}"
        new_options = add_kramdown_options(opts, options, banner: ["#{ext} options:"],
                                           ignore: defined_options)
        defined_options.concat(new_options)
      rescue LoadError
        $stderr.puts "Couldn't load extension #{ext}, ignoring"
      end
    end
  end
  opts.separator ""
  opts.on("--no-config-file", "Do not read any configuration file. Default behavior is to check " \
          "for a", "configuration file and read it if it exists.") { config_file = nil }
  opts.on("--config-file FILE", "Specify the name of a configuration file with kramdown options " \
          "in YAML", "format, e.g. \"auto_id_prefix: ARG\" instead of \"--auto-id-prefix ARG\"",
          "and \"auto_ids: false\" instead of \"--no-auto-ids\".",
          "Default: #{config_file}") {|v| config_file = v }
  opts.separator ""
  opts.on("-v", "--version", "Show the version of kramdown") do
    puts Kramdown::VERSION
    exit
  end
  opts.on("-h", "--help", "Show the help") do
    puts opts.summarize('', 5, 72)
    exit
  end

  new_options = add_kramdown_options(opts, options, banner: ["kramdown options:"])
  defined_options.concat(new_options)
end.parse!

begin
  if config_file && File.exist?(config_file)
    config_file_options = YAML.safe_load(File.read(config_file), [Symbol])
    case config_file_options
    when nil # empty configuration file except perhaps YAML header and comments
      # Nothing to do
    when Hash
      options = config_file_options.merge(options)
    else
      raise Kramdown::Error, "No YAML map in configuration file \"#{config_file}\""
    end
  end
  doc = Kramdown::Document.new(ARGF.read, options)
  result = ''
  format.each {|f| result = doc.send("to_#{f}") }
  puts result
  doc.warnings.each {|warn| $stderr.puts "Warning: #{warn}" }
rescue Kramdown::Error => e
  $stderr.puts "Error: #{e.message}"
  exit(1)
end