# frozen_string_literal: true

class Import::GithubController < Import::BaseController
  include ImportHelper

  before_action :verify_import_enabled
  before_action :provider_auth, only: [:status, :realtime_changes, :create]
  before_action :expire_etag_cache, only: [:status, :create]

  rescue_from Octokit::Unauthorized, with: :provider_unauthorized

  def new
    if !ci_cd_only? && github_import_configured? && logged_in_with_provider?
      go_to_provider_for_permissions
    elsif session[access_token_key]
      redirect_to status_import_url
    end
  end

  def callback
    session[access_token_key] = client.get_token(params[:code])
    redirect_to status_import_url
  end

  def personal_access_token
    session[access_token_key] = params[:personal_access_token]&.strip
    redirect_to status_import_url
  end

  def status
    # Request repos to display error page if provider token is invalid
    # Improving in https://gitlab.com/gitlab-org/gitlab-ce/issues/55585
    client_repos

    respond_to do |format|
      format.json do
        render json: { imported_projects: serialized_imported_projects,
                       provider_repos: serialized_provider_repos,
                       namespaces: serialized_namespaces }
      end
      format.html
    end
  end

  def create
    result = Import::GithubService.new(client, current_user, import_params).execute(access_params, provider)

    if result[:status] == :success
      render json: serialized_imported_projects(result[:project])
    else
      render json: { errors: result[:message] }, status: result[:http_status]
    end
  end

  def realtime_changes
    Gitlab::PollingInterval.set_header(response, interval: 3_000)

    render json: find_jobs(provider)
  end

  private

  def import_params
    params.permit(permitted_import_params)
  end

  def permitted_import_params
    [:repo_id, :new_name, :target_namespace]
  end

  def serialized_imported_projects(projects = already_added_projects)
    ProjectSerializer.new.represent(projects, serializer: :import, provider_url: provider_url)
  end

  def serialized_provider_repos
    repos = client_repos.reject { |repo| already_added_project_names.include? repo.full_name }
    ProviderRepoSerializer.new(current_user: current_user).represent(repos, provider: provider, provider_url: provider_url)
  end

  def serialized_namespaces
    NamespaceSerializer.new.represent(namespaces)
  end

  def already_added_projects
    @already_added_projects ||= find_already_added_projects(provider)
  end

  def already_added_project_names
    @already_added_projects_names ||= already_added_projects.pluck(:import_source) # rubocop:disable CodeReuse/ActiveRecord
  end

  def namespaces
    current_user.manageable_groups_with_routes
  end

  def expire_etag_cache
    Gitlab::EtagCaching::Store.new.tap do |store|
      store.touch(realtime_changes_path)
    end
  end

  def client
    @client ||= Gitlab::LegacyGithubImport::Client.new(session[access_token_key], client_options)
  end

  def client_repos
    @client_repos ||= client.repos
  end

  def verify_import_enabled
    render_404 unless import_enabled?
  end

  def go_to_provider_for_permissions
    redirect_to client.authorize_url(callback_import_url)
  end

  def import_enabled?
    __send__("#{provider}_import_enabled?") # rubocop:disable GitlabSecurity/PublicSend
  end

  def realtime_changes_path
    public_send("realtime_changes_import_#{provider}_path", format: :json) # rubocop:disable GitlabSecurity/PublicSend
  end

  def new_import_url
    public_send("new_import_#{provider}_url", extra_import_params) # rubocop:disable GitlabSecurity/PublicSend
  end

  def status_import_url
    public_send("status_import_#{provider}_url", extra_import_params) # rubocop:disable GitlabSecurity/PublicSend
  end

  def callback_import_url
    public_send("users_import_#{provider}_callback_url", extra_import_params) # rubocop:disable GitlabSecurity/PublicSend
  end

  def provider_unauthorized
    session[access_token_key] = nil
    redirect_to new_import_url,
      alert: "Access denied to your #{Gitlab::ImportSources.title(provider.to_s)} account."
  end

  def access_token_key
    :"#{provider}_access_token"
  end

  def access_params
    { github_access_token: session[access_token_key] }
  end

  # The following methods are overridden in subclasses
  def provider
    :github
  end

  def provider_url
    strong_memoize(:provider_url) do
      provider = Gitlab::Auth::OAuth::Provider.config_for('github')

      provider&.dig('url').presence || 'https://github.com'
    end
  end

  # rubocop: disable CodeReuse/ActiveRecord
  def logged_in_with_provider?
    current_user.identities.exists?(provider: provider)
  end
  # rubocop: enable CodeReuse/ActiveRecord

  def provider_auth
    if !ci_cd_only? && session[access_token_key].blank?
      go_to_provider_for_permissions
    end
  end

  def ci_cd_only?
    %w[1 true].include?(params[:ci_cd_only])
  end

  def client_options
    {}
  end

  def extra_import_params
    {}
  end
end
