class BulletTrain::Themes::Light::CustomThemeFileReplacer

def initialize(original_theme, custom_theme)
  @original_theme = original_theme
  @custom_theme = custom_theme
  @repo_path = "./local/bullet_train-themes-#{@custom_theme}"
end

def remove_custom_theme_from_main_app
  files = [
    "./app/assets/stylesheets/#{@custom_theme}.tailwind.css",
    Dir.glob("./app/assets/stylesheets/#{@custom_theme}/**/*.css"),
    "./app/javascript/application.#{@custom_theme}.js",
    "./app/lib/bullet_train/themes/#{@custom_theme}.rb",
    Dir.glob("./app/views/themes/#{@custom_theme}/**/*.html.erb"),
  ].flatten
  files.each do |file|
    File.delete(file)
  end
  directories = [
    "./app/assets/stylesheets/#{@custom_theme}/",
    "./app/views/themes/#{@custom_theme}/",
    "./app/lib/"
  ].map { |directory| directory unless directory == "./app/lib/" && Dir.empty?(directory) }
  directories.compact.each { |directory| FileUtils.rm_rf(directory) }
end

def rename_cloned_files_and_directories_with_custom_theme_name
  cloned_contents = Dir.glob("#{@repo_path}/**/*")
  cloned_directories = cloned_contents.select { |repo_content| File.directory?(repo_content) && repo_content.match?(/\/#{@original_theme}$/) }
  cloned_files = cloned_contents.select { |repo_content| File.file?(repo_content) && repo_content.split("/").last.match?(@original_theme) }
  (cloned_directories + cloned_files).each do |original_content|
    File.rename(original_content, original_content.gsub(@original_theme, @custom_theme))
  end
end

def replace_cloned_file_contents_with_custom_theme_contents
  repo_contents = Dir.glob("#{@repo_path}/**/*")
  cloned_files = repo_contents.select { |repo_content| File.file?(repo_content) && repo_content.match?(@custom_theme) }
  # Most files in the root of the starter repository should not replace what we cloned from the original theme gem.
  (Dir.glob("#{@repo_path}/*") << "#{@repo_path}/config/routes.rb").each { |file_to_skip| cloned_files.delete(file_to_skip) }
  cloned_files.each do |cloned_file|
    starter_repository_file = cloned_file.gsub(@repo_path, ".")
    # This file has a different directory structure than what is in the starter repository.
    starter_repository_file.gsub!("app/", "") if cloned_file.match?("lib/bullet_train/themes/#{@custom_theme}.rb")
    # Some files we have here like the gemspec don't exist in the starter repository, so we skip those.
    if File.exist?(starter_repository_file)
      begin
        BulletTrain::Themes::Light::FileReplacer.replace_content(old: cloned_file, new: starter_repository_file)
      rescue Errno::ENOENT => _
        puts "Couldn't replace contents for #{cloned_file}".red
      end
    end
  end
  # This is the only file that is copied from and pasted to the starter repository directly with
  # a new name when running the eject command, so we have to move it manually to the new gem.
  `mv ./tailwind.#{@custom_theme}.config.js #{@repo_path}/tailwind.#{@custom_theme}.config.js`
end

def replace_theme
  rename_cloned_files_and_directories_with_custom_theme_name
  replace_cloned_file_contents_with_custom_theme_contents
  transform_file_contents_with_custom_theme_name
  remove_custom_theme_from_main_app
  set_gem_to_v1
  update_gem_author_and_email
end

def set_gem_to_v1
  new_lines = []
  File.open("#{@repo_path}/lib/bullet_train/themes/#{@custom_theme}/version.rb", "r") do |file|
    new_lines = file.readlines
    new_lines = new_lines.map { |line| line.match?("VERSION") ? "      VERSION = \"1.0\"\n" : line }
  end
  File.open("#{@repo_path}/lib/bullet_train/themes/#{@custom_theme}/version.rb", "w") do |file|
    file.puts new_lines.join
  end
end

def transform_file_contents_with_custom_theme_name
  repo_contents = Dir.glob("#{@repo_path}/**/*")
  files_to_change = repo_contents.select { |repo_content| File.file?(repo_content) }
  original_theme_class_name = @original_theme.split(/[_|-]/).map(&:capitalize).join
  custom_theme_class_name = @custom_theme.split(/[_|-]/).map(&:capitalize).join
  new_lines = []
  files_to_change.each do |file|
    File.open(file, "r") do |f|
      new_lines = f.readlines
      next unless new_lines.join.match?(/#{@original_theme}|#{original_theme_class_name}/)
      new_lines = new_lines.map do |line|
        # Avoid replacing Tailwind styles like `font-light` and `font-extralight`.
        line.gsub!(@original_theme, @custom_theme) unless line.match?(/font-.*light/)
        line.gsub!(original_theme_class_name, custom_theme_class_name)
        line
      end
    end
    File.open(file, "w") do |f|
      f.puts new_lines.join
    end
  end
end

def update_gem_author_and_email
  # If the developer hasn't set these yet, this should simply return empty strings.
  author = `git config --global user.name`.chomp
  email = `git config --global user.email`.chomp
  new_lines = []
  File.open("#{@repo_path}/bullet_train-themes-#{@custom_theme}.gemspec", "r") do |file|
    new_lines = file.readlines
    new_lines = new_lines.map do |line|
      if line.match?("spec.authors")
        "  spec.authors = [\"#{author}\"]\n"
      elsif line.match?("spec.email")
        "  spec.email = [\"#{email}\"]\n"
      else
        line
      end
    end
  end
  File.open("#{@repo_path}/bullet_train-themes-#{@custom_theme}.gemspec", "w") do |file|
    file.puts new_lines.join
  end
end