sapristi-tool/sapristi

# frozen_string_literal: true

require 'wmctrl'

module Sapristi
  module Linux
    class WindowManager
      def initialize(display = WMCtrl.display)
        @display = display
      end

      attr_reader :display

      def close(window)
        @display.action_window(window.id, :close)

        #
        # sleep to allow a Graceful Dead to the window process
        #
        # X Error of failed request:  BadWindow (invalid Window parameter)
        #   Major opcode of failed request:  20 (X_GetProperty)
        #   Resource id in failed request:  0x2200008
        #   Serial number of failed request:  1095
        #   Current serial number in output stream:  1095
        sleep TIME_TO_APPLY_DIMENSIONS
      end

      def windows(args = {})
        @display.windows args
      end

      def workspaces
        @display.desktops
      end

      GRAVITY = 0
      TIME_TO_APPLY_DIMENSIONS = 0.25

      def move(window, x_position, y_position)
        geometry = complete_geometry(window.id, x_position: x_position, y_position: y_position)
        move_resize(window, geometry)
      end

      def resize(window, width, height)
        geometry = complete_geometry(window.id, width: width, height: height)
        move_resize(window, geometry)
      end

      def move_resize(window, requested)
        remove_extended_hints(window) if window.maximized_horizontally? || window.maximized_vertically?

        geometry = requested.clone
        left, right, top, bottom = window.frame_extents || [0, 0, 0, 0]
        geometry[2] -= left + right
        geometry[3] -= top + bottom

        @display.action_window(window.id, :move_resize, GRAVITY, *geometry)
        sleep TIME_TO_APPLY_DIMENSIONS
        check_expected_geometry window, requested
      end

      def to_workspace(window, workspace)
        @display.action_window(window.id, :move_to_desktop, workspace)
        sleep TIME_TO_APPLY_DIMENSIONS
      end

      private

      EXTENDED_HINTS = %w[maximized_vert maximized_horz].freeze

      def remove_extended_hints(window)
        display.action_window(window.id, :change_state, 'remove', *EXTENDED_HINTS)
        sleep TIME_TO_APPLY_DIMENSIONS
      end

      def complete_geometry(window_id, requested)
        window = @display.windows(id: window_id).first
        Geometry.new(window).merge(requested)
      end

      LABELS = %w[x y width heigth].freeze

      def check_expected_geometry(window, expected)
        actual_window = @display.windows(id: window.id).first
        actual = actual_window.exterior_frame || actual_window.geometry

        return if actual.eql? expected

        # rubocop:disable Layout/LineLength
        ::Sapristi.logger.warn "Geometry mismatch #{WindowManager.text_diff(actual, expected)}, requested=#{expected}, window=#{window.title}"
        # rubocop:enable Layout/LineLength
      end

      def self.text_diff(actual, expected)
        diffs = 4.times.filter { |index| !expected[index].eql? actual[index] }
        diffs.map do |diff_index|
          "#{LABELS[diff_index]}: expected=#{expected[diff_index]}, actual=#{actual[diff_index]}"
        end.join(', ')
      end
    end

    class Geometry
      def initialize(window)
        @geometry = window.exterior_frame || window.geometry
      end

      attr_reader :geometry

      def merge(requested)
        [requested.fetch(:x_position, geometry[0]),
         requested.fetch(:y_position, geometry[1]),
         requested.fetch(:width, geometry[2]),
         requested.fetch(:height, geometry[3])]
      end
    end
  end
end