module TTY::Markdown

def build_symbols(symbols)
  case symbols
  when String, Symbol
    select_symbols(symbols)
  when Hash
    base_symbols = select_symbols(symbols[:base])
    base_symbols.merge(symbols[:override].to_h)
  else
    SYMBOLS
  end
end

def build_theme(theme)
  THEME.merge(theme.to_h) do |*, new_style|
    Array(new_style).map(&:to_sym)
  end
end

def color_enabled(color)
  case color.to_s
  when "always" then true
  when "never"  then false
  end
end

def parse(source,
          color: :auto,
          indent: 2,
          mode: TTY::Color.mode,
          symbols: {},
          theme: {},
          width: TTY::Screen.width,
          **doc_opts)
  converter_options = {
    enabled: color_enabled(color),
    indent: indent,
    input: "KramdownExt",
    mode: mode,
    symbols: build_symbols(symbols),
    theme: build_theme(theme),
    width: width
  }
  doc = Kramdown::Document.new(source, converter_options.merge(doc_opts))
  Converter.convert(doc.root, doc.options).join
end

def parse_file(path, **options)
  parse(::File.read(path), **options)
end

def select_symbols(name)
  name.to_s == "ascii" ? ASCII_SYMBOLS : SYMBOLS
end