require 'rouge'

# FIXME This whole file has a weird vibe. It has dead code and 
# also exposes methods that are not dot commands...

def self.pyg_change(code, klass, style)
  color = style[0..6]
  modifier = style[8]
  mod_open = modifier ? "<#{modifier}>" : ""
  mod_close = modifier ? "</#{modifier}>" : ""
  rx = /<span class="#{klass}">(?<cname>[^<]+?)<\/span>/
  loop do
    md = rx.match(code)
    break if md.nil?
    str = md[:cname]
    result = code.sub!(rx, "<font color=#{color}>#{mod_open}#{str}#{mod_close}</font>")
    break if result.nil?
  end
end

def self._codebar_color(lexer)
  color = case lexer
    when :elixir
      "#fc88fc"
    when :ruby
      "#fc8888"
    else
      raise "Unknown lexer"
  end
end

def self.pyg_finalize(code, lexer=:elixir)
  Styles.each_pair {|klass, style| pyg_change(code, klass, style) }
  code.sub!(/<pre>/, "<pre>\n")
  code.gsub!(/<span class="[np]">/, "")
  code.gsub!(/<\/span>/, "")
  color = _codebar_color(lexer)
  code.sub!(/<td class="linenos"/, "<td width=2%></td><td width=5% bgcolor=#{color}")
  code.gsub!(/<td/, "<td valign=top ")
  code.gsub!(/ class="[^"]*?"/, "")    # Get rid of remaining Pygments CSS
  lines = code.split("\n")
  n1 = lines.index {|x| x =~ /<pre>/ }
  n2 = lines.index {|x| x =~ /<\/pre>/ }
  # FIXME ?
  n1 ||= 0
  n2 ||= -1
  lines[n1].sub!(/ 1$/, "  1 ")
  (n1+1).upto(n2) {|n| lines[n].replace(" " + lines[n] + " ") }
  code = lines.join("\n")
  code
end

def _process_code(text)
  lines = text.split("\n")
  lines = lines.select {|x| x !~ /##~ omit/ }
  @refs = {}
  lines.each.with_index do |line, i|
    if line =~ /##~ ref/
      frag, name = line.split(/ *##~ ref/)
      @refs[name.strip] = i
      line.replace(frag)
    end
  end
  lines.map! {|line| "  " + line }
  text2 = lines.join("\n")
  text.replace(text2)
end

def _colorize(code, lexer=:elixir)
  text = ::Pygments.highlight(code, lexer: lexer, options: {linenos: "table"})
  _debug "--- in _colorize: text = #{text.inspect}"
  text2 = PygmentFix.pyg_finalize(text, lexer)
  result = "<!-- colorized code -->\n" + text2
  result
end

def _colorize!(code, lexer=:elixir)
  text = ::Pygments.highlight(code, lexer: lexer, options: {})
  _debug "--- in _colorize!: text = #{text.inspect}"
  text2 = PygmentFix.pyg_finalize(text, lexer)
  result = "<!-- colorized code -->\n" + text2
  result
end

def fragment
  lang = @_args.empty? ? :elixir : @_args.first.to_sym   # ruby or elixir
  @_args = []
# TTY.puts "\n#{self.inspect}"
  send(lang)
  _out "\n"
end

def code       # FIXME ?
  text = ""   
  _body {|line| _out "    " + line }
end

def mono
  _out "<pre>"
  _body {|line| _out "    " + line }
  _out "</pre>"
end

def create_code_styles
  dir = @_outdir || "."
  theme, back = "Github", "white"
  css = Rouge::Themes.const_get(theme).render(scope: '.rb_highlight')
  added = <<~CSS
    .rb_highlight { 
    font-family: 'Monaco', 'Andale Mono', 'Lucida Grande', 'Courier', 'Lucida Console', 'Courier New', monospace;
    white-space: pre; 
    background-color: #{back} 
    }
  CSS

  css.gsub!(/{\n/, "{\n  font-family: courier;")
  css = added + "\n" + css
  # STDERR.puts "Writing #{theme} theme to ruby.css"
  File.write("#{dir}/ruby.css", css)

  css = Rouge::Themes.const_get(theme).render(scope: '.ex_highlight')
  added = added.sub(/rb/, "ex")
  css.gsub!(/{\n/, "{\n  font-family: courier;")
  css = added + "\n" + css 
  # STDERR.puts "Writing #{theme} theme to elixir.css"
  File.write("#{dir}/elixir.css", css)
end


def format_ruby(source, theme = "Github", back = "black")
  # theme/back not used now
  formatter = Rouge::Formatters::HTML.new
  lexer = Rouge::Lexers::Ruby.new
  body = formatter.format(lexer.lex(source))
  text = "<div class=rb_highlight>#{body}</div>"
  text
end

def format_elixir(source, theme = "Github", back = "black")
  # theme/back not used now
  formatter = Rouge::Formatters::HTML.new
  lexer = Rouge::Lexers::Elixir.new
  body = formatter.format(lexer.lex(source))
  text = "<div class=ex_highlight>#{body}</div>"
  text
end

def ruby
  file = @_args.first 
  if file.nil?
    code = "  # Ruby code\n\n"
    _body {|line| code << "  " + line + "\n" }
  else
    code = "# Ruby code\n\n" + ::File.read(file)
  end

  html = format_ruby(code)
  _out html
end

def elixir
  file = @_args.first 
  if file.nil?
    code = ""
    _body {|line| code << "  " + line + "\n" }
  else
    code = ::File.read(file)
  end

  html = format_elixir(code)
  _out html
end