haml2erb

#!/usr/bin/env ruby
## frozen_string_literal: true
require 'bundler/inline'
gemfile do
  source 'https://rubygems.org'
  gem "faraday", "~> 2.2"
end

class Converter
  def initialize(filename)
    @content = File.open(filename).read
  end

  attr_reader :content

  def to_erb
    conn = Faraday.new(url: "https://haml2erb.org", headers: {'Content-Type' => 'application/json'})
    response = JSON.parse(conn.post("/api/convert", body.to_json).body)
    raise response["error"] unless response["success"]
    decode(response["erb"])
  end

  private

  def body
    {haml: encode(content)}
  end

  ### convert UTF-8 to ASCII
  def to_ascii(str)
    str.encode("ASCII", :invalid => :replace, :undef => :replace, :replace => "???")
  end

  def encode(str)
    result = ""
    str.each_char do |c|
      result = (c.ord > 127) ? result + "&#" + c.ord.to_s + ";" : result + c
    end
    result
  end

  def decode(str)
    str = str.gsub(/&#(\d+);/) {|m| $1.to_i.chr(Encoding::UTF_8)}
    replace_inline_ruby(str)
  end

  def replace_inline_ruby(str)
    str.gsub(/#\{(.*?)}/, '<%= \1 %>')
  end
end

if __FILE__ == $PROGRAM_NAME
  if ARGV.empty?
    puts "Usage: #{$PROGRAM_NAME} <hamlfile>"
    puts "or: #{$PROGRAM_NAME} <view-directory>"
    exit(1)
  end

  if File.directory?(ARGV[0])
    Dir.glob(ARGV[0] + "/*.haml").each do |haml_file|
      puts "Converting #{haml_file}..."
      converter = Converter.new(haml_file)
      File.open(haml_file.sub(/\.haml$/, ".erb"), "w") do |f|
        f.write(converter.to_erb)
      end
      File.delete(haml_file)
    end
  else
    haml_file = ARGV[0]
    raise "File is not a haml file" if !haml_file.end_with?(".haml") || !File.exist?(haml_file)
    erb_file = haml_file.sub(".haml", ".erb")
    converter = Converter.new(haml_file)
    File.open(erb_file, 'w') { |f| f.write(converter.to_erb) }
  end
end