class SvelteOnRails::Renderer

def initialize(component_name, base_path: SvelteOnRails::Configuration.instance.components_folder_full)
  config = SvelteOnRails::Configuration.instance
  unless system("#{config.node_bin_path} --version > /dev/null 2>&1")
    raise "Node.js not found at '#{config.node_bin_path}'. Please configure SvelteOnRails.node_bin (e.g., to ~/.nvm/versions/node/vX.Y.Z/bin/node) or ensure 'node' is in the PATH. If using NVM, run `nvm which default` to find the path."
  end
  if !Dir.exist?(config.ssr_dist_folder) || config.watch_changes?
    SvelteOnRails::Lib::Utils.watch_changes_and_precompile
  end
  utils = SvelteOnRails::Lib::Utils
  @component_files = utils.component_files(component_name, base_path: base_path)
end

def render(props = {})
  require 'base64'
  require 'json'
  utils = SvelteOnRails::Lib::Utils
  cnf = SvelteOnRails::Configuration.instance
  cmd = [
    cnf.node_bin_path,
    File.join(utils.gem_app_dir, 'renderer', 'render.js'),
    @component_files[:compiled_file] + '.js',
    cnf.rails_root
  ].join(' ')
  Dir.chdir(cnf.rails_root) do
    stdout, stderr, status = Open3.capture3(cmd, stdin_data: props.to_json, chdir: cnf.rails_root)
    begin
      res = JSON.parse(stdout)
      css_file = @component_files[:compiled_file] + '.css'
      if File.exist?(css_file)
        res['css'] = File.read(css_file)
      end
      unless status.to_s.match(/^pid [0-9]+ exit 0$/)
        cmp = "#{@component_files[:svelte_filename]} was returned «#{status.to_s}»\n\n"
        msg = "#{cmp}output from render.js (stderr) =>\n+++\n" + stderr + "+++\n\nRender Svelte Server-side =>\n#{cmd}\n\n"
        utils.puts_warning(msg)
      end
      return res
    rescue JSON::ParserError => e
      raise "[svelte-on-rails] render ERROR Svelte Server-side: Expected JSON, got: «#{stdout}»\n\ncomponent: #{@component_files[:svelte_filename]}\n\nstdout:\n+++\n#{stderr}+++\n\ncmd: «#{cmd}»"
    end
  end
end