# frozen_string_literal: true

class ApplicationController < ActionController::Base
  class ReadOnlyError < StandardError; end
  class FeatureUnavailableError < StandardError; end

  before_action :set_view_path
  before_action :initialize_session
  before_action :normalize_search
  before_action :set_common_headers
  helper_method :site_domain, :assets_path, :safe_site_name, :site_title, :site_color, :controller_param, :action_param, :body_class, :stimulus_class
  skip_before_action :verify_authenticity_token

  rescue_from Exception, with: :rescue_exception

  def set_view_path
    prepend_view_path(Rails.root.join("app", "views", safe_site_name))
  end

  def set_common_headers
    Websites.config.common_headers(request.domain).each do |key, value|
      response.headers[key] = value
    end
  end

  def initialize_session
    WebLogger.initialize(request)
    CurrentUser.user = APIUser.anonymous
    CurrentUser.ip_addr = request.remote_ip
  end

  def site_domain
    "unknown"
  end

  def assets_path
    site_domain
  end

  def site_title
    "Unknown"
  end

  def site_color
    "#2C2F33"
  end

  def safe_site_name
    site_domain.parameterize.dasherize
  end

  def controller_param
    return "unknown" unless params[:controller]
    name = params[:controller].parameterize.dasherize
    name = name.gsub("#{safe_site_name}-", "") if name.include?(safe_site_name)
    name
  end

  def action_param
    return "unknown" unless params[:action]
    params[:action]
  end

  def body_class
    "s-#{safe_site_name} c-#{controller_param} a-#{action_param}"
  end

  def stimulus_class
    params[:controller].gsub("/", "--").dasherize
  end

  def track_usage(service)
    APIUsage.create!(
      user_id:    CurrentUser.is_anonymous? ? nil : CurrentUser.id,
      api_key:    @apikey.nil? || @apikey.is_anon? ? nil : @apikey,
      user_agent: request.headers["user-agent"],
      method:     request.method,
      path:       request.path,
      params:     request.params.to_json,
      service:    service,
      ip_addr:    request.remote_ip,
    )
  end

  module CommonAssetRoutes
    def manifest
      render(partial: "manifest", layout: false)
    end

    def browserconfig
      render(partial: "browserconfig", layout: false)
    end
  end

  module CommonRoutes
    def online
      render(json: {
        success: true,
        uptime:  Time.now - Websites::STARTED_AT,
      })
    end

    def access_denied(message: nil, code: nil)
      @message = message.present? ? "Access Denied: #{message}" : "Access Denied"
      @code = code
      respond_to do |fmt|
        fmt.html { render("static/access_denied", status: 403) }
        fmt.json do
          render(json: {
            success: false,
            message: @message,
            code:    @code,
          }, status: 403)
        end
      end
    end

    def not_found(code: nil)
      @code = code
      respond_to do |fmt|
        fmt.any { render("static/not_found", status: 404) }
        fmt.json do
          render(json: {
            success: false,
            message: "Not found.",
            code:    @code,
          }, status: 404)
        end
      end
    end

    def readonly
      respond_to do |fmt|
        fmt.html { render("static/readonly", status: YiffyAPIErrorCodes::READONLY.status) }
        fmt.json { render_error(YiffyAPIErrorCodes::READONLY, message: "This service is currently in read only mode. Try again later.") }
      end
    end

    private

    def render_error(*, **)
      extend(YiffyAPIUtil).render_error(*, **)
    end
  end

  module RenderMethods
    def handle_error
      @exception = request.env["action_dispatch.exception"]
      @status_code = @exception.try(:status_code) ||
                     ActionDispatch::ExceptionWrapper.new(
                       request.env, @exception
                     ).status_code
      return not_found if @status_code == 404
      return rescue_exception(@exception) if @exception
      render_error_page(@status_code, Exception.new("An unexpected error occurred."))
    end

    def rescue_exception(exception)
      @exception = exception
      case exception
      when ActiveRecord::RecordNotFound
        not_found
      when ReadOnlyError
        readonly
      when PG::Error
        render_error_page(503, exception, message: "The database is unavailable. Try again later.")
      when ActionController::ParameterMissing, ActionController::UnpermittedParameters
        render_expected_error(400, exception.message)
      when ActionController::RoutingError
        render_error_page(405, exception)
      when ActionController::UnknownFormat, ActionView::MissingTemplate
        render_unsupported_format
      when ActionController::InvalidAuthenticityToken
        access_denied(message: "Invalid CSRF Token")
      else
        render_error_page(500, exception)
      end
    end

    def render_unsupported_format
      return not_found if request.format.nil?
      render_expected_error(406, "#{request.format} is not a supported format for this page", format: :html)
    end

    def render_expected_error(status, message, format: request.format.symbol)
      format = :html unless format.in?(%i[html json])
      @message = message
      @log_code = nil
      render("static/error", status: status, formats: format)
    end

    def render_error_page(status, exception, message: exception.message, format: request.format.symbol)
      @exception = exception
      @expected = status < 500
      @message = message.encode("utf-8", invalid: :replace, undef: :replace)
      @backtrace = Rails.backtrace_cleaner.clean(@exception.backtrace)
      format = :html unless format.in?(%i[html json])

      @message = "An unexpected error occurred." if !(Rails.env.development? || CurrentUser.is_admin?) && message == exception.message

      WebLogger.log_exception(@exception, expected: @expected)
      log = ExceptionLog.add(exception, request) unless @expected
      @log_code = log&.code
      render("static/error", status: status, formats: format)
    end
  end

  module SearchMethods
    def normalize_search
      return unless request.get? || request.head?
      params[:search] ||= ActionController::Parameters.new

      deep_reject_blank = ->(hash) do
        hash.reject { |_k, v| v.blank? || (v.is_a?(Hash) && deep_reject_blank.call(v).blank?) }
      end
      if params[:search].is_a?(ActionController::Parameters)
        nonblank_search_params = deep_reject_blank.call(params[:search])
      else
        nonblank_search_params = ActionController::Parameters.new
      end

      if nonblank_search_params != params[:search]
        params[:search] = nonblank_search_params
        redirect_to(url_for(params: params.except(:controller, :action, :index).permit!))
      end
    end

    def search_params
      params.fetch(:search, {}).permit!
    end

    def permit_search_params(permitted_params)
      params.fetch(:search, {}).permit(%i[id created_at updated_at] + permitted_params)
    end
  end

  module ReadonlyMethods
    extend ActiveSupport::Concern
    def enforce_readonly
      return unless Websites.config.readonly?
      raise(ReadOnlyError) unless allowed_readonly_actions.include?(action_name)
    end

    def allowed_readonly_actions
      %w[index show]
    end

    included do
      before_action :enforce_readonly
    end
  end

  include CommonRoutes
  include RenderMethods
  include SearchMethods
  include Pagy::Backend
end