File indexing completed on 2024-04-28 05:36:15

 /*
  *   SPDX-FileCopyrightText: 2014 Nikita Skovoroda <chalkerx@gmail.com>
  *
  *   SPDX-License-Identifier: GPL-2.0-or-later
  */
 
 #pragma once
 
 namespace PowerDevil
 {
 class BrightnessLogic
 {
 public:
     BrightnessLogic();
     virtual ~BrightnessLogic() = default;
 
     /**
      * This enum defines the different types brightness keys.
      *
      * - Increase: Key to increase brightness (Qt::Key_MonBrightnessUp or Qt::Key_KeyboardBrightnessUp)
      * - Decrease: Key to decrease brightness (Qt::Key_MonBrightnessDown or Qt::Key_KeyboardBrightnessDown)
      * - Toggle: Key to toggle backlight (Qt::Key_KeyboardBacklightOnOff)
      * - IncreaseSmall: Key to increase brightness by 1% (Qt::Key_MonBrightnessUp or Qt::Key_KeyboardBrightnessUp + Qt::ShiftModifier)
      * - DecreaseSmall: Key to decrease brightness by 1% (Qt::Key_MonBrightnessDown or Qt::Key_KeyboardBrightnessDown + Qt::ShiftModifier)
      */
     enum BrightnessKeyType {
         Increase,
         Decrease,
         Toggle,
         IncreaseSmall,
         DecreaseSmall,
     };
 
     /**
      * This struct contains information about current brightness state for a single device
      */
     struct BrightnessInfo {
         /** The raw brightness value, from 0 to valueMax */
         int value;
         /** The maximum possible brightness value for this device */
         int valueMax;
         /** The most recent brightness before toggling off */
         int valueBeforeTogglingOff;
         /** The maximum possible brightness step for this device */
         int steps;
     };
 
     /**
      * Sets the current brightness value.
      *
      * @param value Raw brightness value
      */
     void setValue(int value);
 
     /**
      * Sets the maximum brightness value.
      *
      * @param value Maximum brightness value
      */
     void setValueMax(int valueMax);
 
     /**
      * Sets the last active brightness value.
      *
      * @param value Last active brightness value
      */
     void setValueBeforeTogglingOff(int valueBeforeTogglingOff);
 
     /**
      * Calculate new brightness value that should be set by an action.
      *
      * @param type The action type of the key that was pressed.
      * @return The brightness value that the action should set, or -1 if nothing should be done
      */
     int action(BrightnessKeyType type) const;
 
     /**
      * Calculates the brightness value of the closest step upwards.
      * (Closest step that is higher than current brightness value).
      *
      * @return The brightness value of the closest step upwards
      */
     int increased() const;
 
     /**
      * Calculates the brightness value of the closest step downwards.
      * (Closest step that is lower than current brightness value).
      *
      * @return The brightness value of the closest step downwards
      */
     int decreased() const;
 
     /**
      * Calculates the brightness value of the toggled state.
      * (Sets the brightness value to either minimum, last active brightness or maximum).
      *
      * @return The brightness value that should be set, or -1 if nothing should be done
      */
     virtual int toggled() const;
 
     /**
      * Calculates the brightness value of the closest step upwards.
      * (Closest step that is higher than current brightness value).
      *
      * @return The brightness value of the closest step upwards
      */
     int increasedSmall() const;
 
     /**
      * Calculates the brightness value of the closest step downwards.
      * (Closest step that is lower than current brightness value).
      *
      * @return The brightness value of the closest step downwards
      */
     int decreasedSmall() const;
 
     /**
      * Retrieve the maximum possible brightness step for this instance
      *
      * @return Maximum possible brightness step
      */
     int steps() const;
 
     /**
      * Retrieve the supplied brightness value expressed as a percentage from 0 to 100
      *
      * @param value Brightness value, from 0 to valueMax
      * @return The brightness percentage for the supplied value
      */
     float percentage(int value) const;
 
     /**
      * Retrieve a copy of the current brightness state
      *
      * @return A struct that contains the current brightness state.
      */
     const BrightnessInfo info() const;
 
     /**
      * Convert brightness step to raw brightness value
      *
      * @param step Brightness step, from 0 to steps
      * @return Brightness value that corresponds to the given step
      */
     int stepToValue(int step) const;
 
     /**
      * Retrieve the minimum practical brightness value for this device. Defaults
      * to 0, but should be overridden in subclasses to be a higher value for device
      * types where a higher minimum value brightness makes sense. For example,
      * for screens where a value of 0 sometimes turns off the backlight completely,
      * which is not wanted there.
      *
      * @return Minimum practical brightness value
      */
     virtual int valueMin() const
     {
         return 0;
     }
 
 protected:
     /**
      * Calculate the optimal number of brightness steps.
      *
      * It should be based on three assumptions:
      * 1) The user generally expects to see equal brightness steps, and likes round percentage numbers.
      * 2) Actual brightness is rounded to whole percents before being displayed to the user.
      * 3) An assumption on a generally good number of brightness steps, which varies with implementations.
      *
      * This function does not depend on anything except the argument.
      *
      * @param valueMax the maximum brightness value for which we want to calculate the number of steps
      * @return the optimal maximum step number
      */
     virtual int calculateSteps(int valueMax) const = 0;
 
 private:
     int m_value = -1;
     int m_valueMax = -1;
     int m_valueBeforeTogglingOff = -1;
     int m_steps = -1;
 };
 
 }