class SvelteOnRails::Compiler

def self.reset_and_compile_all
  SvelteOnRails::RenderServerSide.reset_dist
  cnf = SvelteOnRails::Configuration.instance
  frontend_folder = cnf.frontend_folder_full
  sveltes = Dir.glob(cnf.frontend_folder_full.join('**/*.svelte'))
  sveltes.each_with_index do |file, ind|
    comp_name = file.to_s[(cnf.frontend_folder_full.to_s.length + 1)..-1]
    n = SvelteOnRails::RenderServerSide.new(comp_name, base_path: frontend_folder)
    n.compile
    puts "compiled #{ind + 1}/#{sveltes.length}: #{comp_name}"
  end
end

def self.reset_dist
  unless Dir.exist?(SvelteOnRails::Configuration.instance.dist_folder)
    FileUtils.mkdir_p(SvelteOnRails::Configuration.instance.dist_folder)
  end
  FileUtils.rm_rf Dir.glob("#{SvelteOnRails::Configuration.instance.dist_folder}/*")
  FileUtils.touch SvelteOnRails::Configuration.instance.dist_folder.join('reset_timestamp')
end

def compile
  start_time = Time.now
  cnf = SvelteOnRails::Configuration.instance
  subs = @files[:svelte_filename].split('/')[0..-2].join('/')
  dist = cnf.dist_folder + cnf.components_folder + subs
  utils = SvelteOnRails::Lib::Utils
  cmd = [
    'node',
    utils.gem_app_dir + 'compiler/compile.js',
    @files[:svelte_file],
    dist,
    utils.gem_app_dir
  ].join(' ')
  Dir.chdir(cnf.rails_root) do
    env = { 'NODE_PATH' => File.join(cnf.rails_root, 'node_modules') }
    stdout, stderr, status = Open3.capture3(env, cmd, chdir: cnf.rails_root)
    unless status.to_s.match(/^pid [0-9]+ exit 0$/)
      raise "Compiling «#{@files[:svelte_filename]}» Server-side, script compile.js, executed within Rails.root:\n\n#{cmd}\n\n++++++\n\n#{stderr}\n\n++++++\n\n"
    end
  end
  time = Time.now - start_time
  Rails.logger.info "  Compiled #{@files[:svelte_filename]}.js: #{time.round(3)}ms" rescue nil
end

def compile_if_changes
  # letzte Änderung innerhalb des ordners ermitteln
  watch_changes = SvelteOnRails::Configuration.instance.watch_changes?
  ts_file = SvelteOnRails::Configuration.instance.dist_folder.join('reset_timestamp')
  have_changes = if watch_changes && File.exist?(ts_file)
                   # compare last modification timestamp
                   last_modification = 100.years.ago.to_time
                   Dir.glob("#{SvelteOnRails::Configuration.instance.components_folder}**/*").each do |path|
                     if File.file?(path)
                       mtime = File.mtime(path)
                       if mtime > last_modification
                         last_modification = mtime
                       end
                     end
                   end
                   File.mtime(ts_file) < last_modification
                 elsif watch_changes
                   true
                 elsif !File.exist?(ts_file)
                   true
                 else
                   false
                 end
  if have_changes || !File.exist?(compiled_js_file) || !File.exist?(compiled_css_file)
    if have_changes || (!File.exist?(ts_file) && watch_changes)
      self.class.reset_dist
    end
    compile
  end
end

def compiled_css_file
  @files[:compiled_file] + '.css'
end

def compiled_file
  @files[:compiled_file]
end

def compiled_js_file
  @files[:compiled_file] + '.js'
end

def initialize(filename, base_path: SvelteOnRails::Configuration.instance.components_folder_full)
  utils = SvelteOnRails::Lib::Utils
  @files = utils.component_files(filename, base_path: base_path)
end