module SvelteOnRails::Installer::Vite

def self.configure_for_svelte
  # add import statement
  js_i = SvelteOnRails::Installer::Javascript
  pkg = '@sveltejs/vite-plugin-svelte'
  js_i.append_import_statement('vite.config.ts', pkg, "import {svelte} from '#{pkg}'")
  npm_i = SvelteOnRails::Installer::Npm
  npm_i.install_or_update_package(pkg)
  # add plugin
  file_content = File.read('vite.config.ts')
  if file_content.match?(/svelte/)
    puts "Svelte seams already configured in vite.config.ts, nothing changed here."
  else
    # Regex to match the plugins array and locate RubyPlugin()
    plugins_regex = /(plugins:\s*\[\s*)(\s*)RubyPlugin\(\),\s*([^]]*?\])/m
    # Check if plugins array with RubyPlugin exists
    unless file_content.match?(plugins_regex)
      puts "Error: No plugins array with RubyPlugin() found in the input."
      return file_content
    end
    # Insert svelte({}), after RubyPlugin() with proper indentation
    modified_content = file_content.gsub(plugins_regex) do |match|
      prefix = $1 # Start of plugins array (e.g., "plugins: [")
      indent = '    ' # Indentation before RubyPlugin()
      rest = $3 # Remaining plugins and closing bracket
      "#{prefix}#{indent}RubyPlugin(),\n#{indent}svelte({}),\n#{indent}#{rest}"
    end
    File.write('vite.config.ts', modified_content)
    puts "Updated vite.config.ts with svelte() plugin."
  end
end

def self.install_vite
  iu = SvelteOnRails::Installer::Utils
  puts '-' * 80
  gu = SvelteOnRails::GemUtils
  if gu.check_gem_version('vite_rails')
    puts "vite_rails already installed, skipping this part."
  else
    # check non-existence
    iu.check_file_not_exists('config/vite.json')
    iu.check_file_not_exists('vite.config.ts')
    iu.check_folder_not_exists('app/frontend')
    # install
    gu.install_gem('vite_rails')
    Dir.chdir(Rails.root) do
      `bundle exec vite install`
    end
  end
  # check existence
  iu.check_file_exists('config/vite.json')
  iu.check_file_exists('vite.config.ts')
  iu.check_file_exists('package.json')
  iu.check_file_exists('package-lock.json')
  iu.check_file_exists('app/frontend/entrypoints/application.js')
  iu.check_folder_exists('app/frontend')
  # check npm package version
  ni = SvelteOnRails::Installer::Npm
  ni.install_or_update_package('vite', minimal_version: [6, 1])
end