class ReactOnRails::Generators::InstallGenerator

def add_bin_scripts
  # Copy bin scripts from templates
  template_bin_path = "#{__dir__}/templates/base/base/bin"
  directory template_bin_path, "bin"
  # Make these and only these files executable
  files_to_copy = []
  Dir.chdir(template_bin_path) do
    files_to_copy.concat(Dir.glob("*"))
  end
  files_to_become_executable = files_to_copy.map { |filename| "bin/#{filename}" }
  File.chmod(0o755, *files_to_become_executable)
end

def add_post_install_message
  # Determine what route will be created by the generator
  route = "hello_world" # This is the hardcoded route from base_generator.rb
  component_name = options.redux? ? "HelloWorldApp" : "HelloWorld"
  GeneratorMessages.add_info(GeneratorMessages.helpful_message_after_installation(
                               component_name: component_name,
                               route: route
                             ))
end

def check_node_version
  node_version = `node --version 2>/dev/null`.strip
  return if node_version.blank?
  # Extract major version number (e.g., "v18.17.0" -> 18)
  major_version = node_version[/v(\d+)/, 1]&.to_i
  return unless major_version
  return unless major_version < 18
  warning = <<~MSG.strip
    ⚠️  Node.js version #{node_version} detected.
    React on Rails recommends Node.js 18+ for best compatibility.
    You may experience issues with older versions.
    Consider upgrading: https://nodejs.org/en/
  MSG
  GeneratorMessages.add_warning(warning)
end

def cli_exists?(command)
  system("which #{command} > /dev/null 2>&1")
end

def create_css_module_types
  puts Rainbow("📝 Creating CSS module type definitions...").yellow
  # Ensure the types directory exists
  FileUtils.mkdir_p("app/javascript/types")
  css_module_types_content = <<~TS.strip
    // TypeScript definitions for CSS modules
    declare module "*.module.css" {
      const classes: { [key: string]: string };
      export default classes;
    }
    declare module "*.module.scss" {
      const classes: { [key: string]: string };
      export default classes;
    }
    declare module "*.module.sass" {
      const classes: { [key: string]: string };
      export default classes;
    }
  TS
  File.write("app/javascript/types/css-modules.d.ts", css_module_types_content)
  puts Rainbow("✅ Created CSS module type definitions").green
end

def create_typescript_config
  if File.exist?("tsconfig.json")
    puts Rainbow("⚠️  tsconfig.json already exists, skipping creation").yellow
    return
  end
  tsconfig_content = {
    "compilerOptions" => {
      "target" => "es2018",
      "allowJs" => true,
      "skipLibCheck" => true,
      "strict" => true,
      "noUncheckedIndexedAccess" => true,
      "forceConsistentCasingInFileNames" => true,
      "noFallthroughCasesInSwitch" => true,
      "module" => "esnext",
      "moduleResolution" => "bundler",
      "resolveJsonModule" => true,
      "isolatedModules" => true,
      "noEmit" => true,
      "jsx" => "react-jsx"
    },
    "include" => [
      "app/javascript/**/*"
    ]
  }
  File.write("tsconfig.json", JSON.pretty_generate(tsconfig_content))
  puts Rainbow("✅ Created tsconfig.json").green
end

def ensure_shakapacker_in_gemfile
  return if shakapacker_in_gemfile?
  puts Rainbow("📝 Adding Shakapacker to Gemfile...").yellow
  success = system("bundle add shakapacker --strict")
  return if success
  handle_shakapacker_gemfile_error
end

def ensure_shakapacker_installed
  return if shakapacker_configured?
  print_shakapacker_setup_banner
  ensure_shakapacker_in_gemfile
  install_shakapacker
  finalize_shakapacker_setup
end

def finalize_shakapacker_setup
  puts Rainbow("✅ Shakapacker installed successfully!").green
  puts Rainbow("=" * 80).cyan
  puts Rainbow("🚀 CONTINUING WITH REACT ON RAILS SETUP").cyan.bold
  puts "#{Rainbow('=' * 80).cyan}\n"
  # Create marker file so base generator can avoid copying shakapacker.yml
  File.write(".shakapacker_just_installed", "")
end

def handle_shakapacker_gemfile_error
  error = <<~MSG.strip
    🚫 Failed to add Shakapacker to your Gemfile.
    This could be due to:
    • Bundle installation issues
    • Network connectivity problems
    • Gemfile permissions
    Please try manually:
        bundle add shakapacker --strict
    Then re-run: rails generate react_on_rails:install
  MSG
  GeneratorMessages.add_error(error)
  raise Thor::Error, error unless options.ignore_warnings?
end

def handle_shakapacker_install_error
  error = <<~MSG.strip
    🚫 Failed to install Shakapacker automatically.
    This could be due to:
    • Missing Node.js or npm/yarn
    • Network connectivity issues
    • Incomplete bundle installation
    • Missing write permissions
    Troubleshooting steps:
    1. Ensure Node.js is installed: node --version
    2. Run: bundle install
    3. Try manually: bundle exec rails shakapacker:install
    4. Check for error output above
    5. Re-run: rails generate react_on_rails:install
    Need help? Visit: https://github.com/shakacode/shakapacker/blob/main/docs/installation.md
  MSG
  GeneratorMessages.add_error(error)
  raise Thor::Error, error unless options.ignore_warnings?
end

def install_shakapacker
  puts Rainbow("⚙️  Installing Shakapacker (required for webpack integration)...").yellow
  # First run bundle install to make shakapacker available
  puts Rainbow("📦 Running bundle install...").yellow
  bundle_success = system("bundle install")
  unless bundle_success
    handle_shakapacker_install_error
    return
  end
  # Then run the shakapacker installer
  success = system("bundle exec rails shakapacker:install")
  return if success
  handle_shakapacker_install_error
end

def install_typescript_dependencies
  puts Rainbow("📝 Installing TypeScript dependencies...").yellow
  # Delegate to shared module for consistent dependency management
  add_typescript_dependencies
end

def installation_prerequisites_met?
  !(missing_node? || missing_package_manager? || ReactOnRails::GitUtils.uncommitted_changes?(GeneratorMessages))
end

def invoke_generators
  ensure_shakapacker_installed
  if options.typescript?
    install_typescript_dependencies
    create_css_module_types
    create_typescript_config
  end
  invoke "react_on_rails:base", [],
         { typescript: options.typescript?, redux: options.redux?, rspack: options.rspack? }
  if options.redux?
    invoke "react_on_rails:react_with_redux", [], { typescript: options.typescript? }
  else
    invoke "react_on_rails:react_no_redux", [], { typescript: options.typescript? }
  end
  setup_react_dependencies
end

def missing_node?
  node_missing = ReactOnRails::Utils.running_on_windows? ? `where node`.blank? : `which node`.blank?
  if node_missing
    error = <<~MSG.strip
      🚫 Node.js is required but not found on your system.
      Please install Node.js before continuing:
      • Download from: https://nodejs.org/en/
      • Recommended: Use a version manager like nvm, fnm, or volta
      • Minimum required version: Node.js 18+
      After installation, restart your terminal and try again.
    MSG
    GeneratorMessages.add_error(error)
    return true
  end
  # Check Node.js version if available
  check_node_version
  false
end

def missing_package_manager?
  package_managers = %w[npm pnpm yarn bun]
  missing = package_managers.none? { |pm| cli_exists?(pm) }
  if missing
    error = <<~MSG.strip
      🚫 No JavaScript package manager found on your system.
      React on Rails requires a JavaScript package manager to install dependencies.
      Please install one of the following:
      • npm: Usually comes with Node.js (https://nodejs.org/en/)
      • yarn: npm install -g yarn (https://yarnpkg.com/)
      • pnpm: npm install -g pnpm (https://pnpm.io/)
      • bun: Install from https://bun.sh/
      After installation, restart your terminal and try again.
    MSG
    GeneratorMessages.add_error(error)
    return true
  end
  false
end

def print_generator_messages
  GeneratorMessages.messages.each { |message| puts message }
end

def print_shakapacker_setup_banner
  puts Rainbow("\n#{'=' * 80}").cyan
  puts Rainbow("🔧 SHAKAPACKER SETUP").cyan.bold
  puts Rainbow("=" * 80).cyan
end

def run_generators
  # Set environment variable to skip validation during generator run
  # This is inherited by all invoked generators and persists through Rails initialization
  # See lib/react_on_rails/engine.rb for the validation skip logic
  ENV["REACT_ON_RAILS_SKIP_VALIDATION"] = "true"
  if installation_prerequisites_met? || options.ignore_warnings?
    invoke_generators
    add_bin_scripts
    # Only add the post install message if not using Redux
    # Redux generator handles its own messages
    add_post_install_message unless options.redux?
  else
    error = <<~MSG.strip
      🚫 React on Rails generator prerequisites not met!
      Please resolve the issues listed above before continuing.
      All prerequisites must be satisfied for a successful installation.
      Use --ignore-warnings to bypass checks (not recommended).
    MSG
    GeneratorMessages.add_error(error)
  end
ensure
  # Always clean up ENV variable, even if generator fails
  # CRITICAL: ENV cleanup must come first to ensure it executes even if
  # print_generator_messages raises an exception. This prevents ENV pollution
  # that could affect subsequent processes.
  ENV.delete("REACT_ON_RAILS_SKIP_VALIDATION")
  print_generator_messages
end

def setup_react_dependencies
  setup_js_dependencies
end

def shakapacker_binaries_exist?
  File.exist?("bin/shakapacker") && File.exist?("bin/shakapacker-dev-server")
end

def shakapacker_configured?
  # Check for essential shakapacker configuration files and binaries
  shakapacker_binaries_exist? &&
    File.exist?("config/shakapacker.yml") &&
    File.exist?("config/webpack/webpack.config.js")
end

def shakapacker_in_bundler_specs?(gem_name)
  require "bundler"
  Bundler.load.specs.any? { |s| s.name == gem_name }
rescue StandardError
  false
end

def shakapacker_in_gemfile?
  gem_name = "shakapacker"
  shakapacker_in_gemfile_text?(gem_name)
end

def shakapacker_in_gemfile_text?(gem_name)
  gemfile = ENV["BUNDLE_GEMFILE"] || "Gemfile"
  File.file?(gemfile) &&
    File.foreach(gemfile).any? { |l| l.match?(/^\s*gem\s+['"]#{Regexp.escape(gem_name)}['"]/) }
end

def shakapacker_in_lockfile?(gem_name)
  gemfile = ENV["BUNDLE_GEMFILE"] || "Gemfile"
  lockfile = File.join(File.dirname(gemfile), "Gemfile.lock")
  File.file?(lockfile) && File.foreach(lockfile).any? { |l| l.match?(/^\s{4}#{Regexp.escape(gem_name)}\s\(/) }
end

def shakapacker_loaded_in_process?(gem_name)
  Gem.loaded_specs.key?(gem_name)
end