Screen Service
=====================

The screen service provides acces to the (on/off) states of multiple screens in the apartment.
This is solved using the corresponding machines enery management (`dpms <https://de.wikipedia.org/wiki/Display_Power_Management_Signaling>`_) and `xset` via `ssh`.

Related resources
-----------------

Component repository:
 - Browse component repository: `screenservice <https://projects.cit-ec.uni-bielefeld.de/projects/lsp-csra/repository/utils>`_.
 - ``git clone https://projects.cit-ec.uni-bielefeld.de/git/lsp-csra.utils.git``

System startup:
 - The screenservice can be found in ``lsp-csra-base.sh`` on the ``base`` tab.
 - The component script is called ``screenservice``.

Screens
-----------------

Currently the following screens are registered on the following `root scopes`.

========================== ==============================
Monitor Id (host)          Root scope
========================== ==============================
Hallway Flobi (Entrance)   ``/citec/csra/home/hallway/entrance/screen/``
Kitchen Flobi (Assistance) ``/citec/csra/home/kitchen/assistance/screen/``
Living room TV             ``/citec/csra/home/living/hometheater/screen/``
Living room Beamer         ``/citec/csra/home/living/lounge/screen/``
Living room Window         ``/citec/csra/home/living/window/screen/``
Control room Tv's          ``/citec/csra/control/introspection/screen/``
Control room BCO           ``/citec/csra/control/bco/screen/``
Control room Vdemo         ``/citec/csra/control/vdemo/screen/``
========================== ==============================


Interfaces
----------------

All following scopes need to be apended to the screens root scope to access it.

The informers are used to publish the monitors state changes. Changes are published on:

=============================================== ====================
Scope (Informer)                                Type
=============================================== ====================
 ``../status``                                  `Screen`_
=============================================== ====================

.. _Screen: http://docs.cor-lab.de//rst-manual/trunk/html/generated/sandbox/package-rst-homeautomation.html#rst.homeautomation.unit.Screen

Local servers can be used to request or set the screens status. The PowerState method is provided to satisfy the api of homeautomation units.

=========================================== ================ ================
Scope (Local Server) + Method               Parameter Type      Return Type
=========================================== ================ ================
 ``../ctrl/setPower()``                     `PowerState`_    <Error>
 ``../ctrl/getPower()``                                      <Error>
 ``../ctrl/setStandby()``                   `StandbyState`_
 ``../ctrl/getStandby()``                                    `StandbyState`_
 ``../ctrl/requestStatus()``                                 `Screen`_
=========================================== ================ ================

.. _PowerState: http://docs.cor-lab.de//rst-manual/trunk/html/generated/sandbox/package-rst-homeautomation.html#rst.homeautomation.state.PowerState
.. _StandbyState: http://docs.cor-lab.de//rst-manual/trunk/html/generated/sandbox/package-rst-homeautomation.html#rst.homeautomation.state.StandbyState

Examples
--------------

Check the status of the entrance screen:

.. code-block:: bash
   :emphasize-lines: 1,4

    > $prefix/bin/rsb-toolscl call \
          -I $prefix/share/rst0.1*/proto/sandbox \
          -l $prefix/share/rst0.1*/proto/'**/Screen.proto'\
          'spread:/citec/csra/home/hallway/entrance/screen/ctrl/requestStatus("")'

        #<SCREEN {100D5850C3}>
        Id           : "mia"
        Power-State  : #<POWER-STATE {100D5DD343}>
        Value: ON
        Standby-State: #<STANDBY-STATE {100D6348B3}>
        Value: RUNNING
        Label        : "mia"