json configuration

example.cfg

@@ -1,13 +0,0 @@
-[eDP]
-
-[HDMI-A-0]
-
-[eDP-1]
-
-1 = pointer:ELAN9038:00 04F3:2A1C
-2 = pointer:ELAN9038:00 04F3:2A1C Stylus Pen (0)
-3 = pointer:ELAN9038:00 04F3:2A1C Stylus Eraser (0)
-
-4 = pointer:ELAN9038:00 04F3:2A1C touch
-5 = pointer:ELAN9038:00 04F3:2A1C stylus
-6 = pointer:ELAN9038:00 04F3:2A1C eraser

example.json

@@ -0,0 +1,6 @@
+{
+  "screens": ["eDP", "HDMI-A-0", "eDP-1"],
+  "devices": [
+    {"screen": "eDP-1", "name_contains": "ELAN9038:00"}
+  ]
+}

rotate-screen.py

@@ -1,6 +1,6 @@
 #!/usr/bin/env python3
 # -*- coding: utf-8 -*-
-import configparser
+import json
 import subprocess
 import re
 from pathlib import Path
@@ -10,6 +10,9 @@ orientations = ['normal', 'right', 'inverted', 'left']
 
 
 class Screen(NamedTuple):
+    """
+    The xrandr-name of a screen and a list of xinput-device-names that shall be mapped to the screen.
+    """
     name: str
     devices: list[str]
 
@@ -19,49 +22,100 @@ def main():
 
 
 def rotate_clockwise():
-    cfg = get_cfg()
-
-    # screens from cfg that are connected
-    screens = [Screen(name=name, devices=list(cfg[name].values()))
-               for name in cfg
-               if name != cfg.default_section
-               and is_connected(name)]
+    # Screens from configuration that are connected.
+    screens = [screen for screen in Config().get_screens()
+               if Xrandr.is_connected(screen.name)]
 
     if len(screens) == 0:
         raise Exception('None of the configured screens are connected.')
 
-    current_orientation = get_current_orientation(screens[0].name)
+    current_orientation = Xrandr.get_orientation(screens[0].name)
     next_orientation = orientations[(orientations.index(current_orientation) + 1) % len(orientations)]
 
     for screen in screens:
         rotate(screen, next_orientation)
 
 
-def get_cfg() -> configparser.ConfigParser:
-    config: configparser.ConfigParser = configparser.ConfigParser()
-    config.read(get_cfg_path())
-    return config
+def rotate(screen: Screen, orientation):
+    Xrandr.rotate(screen.name, orientation)
+    for device in screen.devices:
+        Xinput.map_to_output(device, screen.name)
 
 
-def get_cfg_path() -> Path:
-    global_path = Path('/etc/rotate-screen.cfg')
+class Config:
+    """
+    Json structure:
+
+        {
+          # List of screen names from xrandr:
+          "screens": ["eDP", "HDMI-A-0", "eDP-1"]
+
+          # List of devices from xinput that shall be mapped to a screen.
+          "devices": [
+            # A device can be identified by its exact name through `name` ...
+            {"screen": "eDP-1", "name": "ELAN9038:00"},
+            # ... or by `name_contains`.
+            {"screen": "eDP-1", "name_contains": "ELAN9038"}
+          ]
+        }
+    """
+
+    def __init__(self):
+        self.screens, self.devices = self.load_json()
+
+    def get_screens(self) -> list[Screen]:
+        return [Screen(name=screen, devices=self.get_devices_for(screen)) for screen in self.screens]
+
+    def get_devices_for(self, screen: str) -> list[str]:
+        device_names = []
+
+        for device in self.devices:
+            if device["screen"] != screen:
+                continue
+            if "name" in device:
+                device_names.append(device["name"])
+            if "name_contains" in device:
+                for x_dev in Xinput.get_device_names():
+                    if device["name_contains"] in x_dev:
+                        device_names.append(x_dev)
+
+        return device_names
+
+    def load_json(self) -> tuple[list[str], list]:
+        j = json.loads(self.get_cfg_path().read_text())
+        if "screens" not in j:
+            raise Exception("'screens' array missing in cfg.")
+        screens = j["screens"]
+
+        if "devices" not in j:
+            raise Exception("'devices' array missing in cfg.")
+        devices = j["devices"]
+        for device in devices:
+            if not "name" in device and not "name_contains" in device:
+                raise Exception("Device must have 'name' or 'name_contains'.")
+
+        return screens, devices
+
+    @classmethod
+    def get_cfg_path(cls) -> Path:
+        global_path = Path('/etc/rotate-screen.json')
         if global_path.exists():
             return global_path
 
-    local_path = Path('example.cfg')
+        local_path = Path('example.json')
         if local_path.exists():
             return local_path
 
         raise Exception('No configuration file found.')
 
 
-def rotate(screen: Screen, orientation):
-    execute(['xrandr', '--output', screen.name, '--rotate', orientation])
-    for device in screen.devices:
-        execute(['xinput', '--map-to-output', device, screen.name])
+class Xrandr:
+    @classmethod
+    def rotate(cls, screen: str, orientation: str):
+        execute(['xrandr', '--output', screen, '--rotate', orientation])
 
-
-def get_current_orientation(screen: str):
+    @classmethod
+    def get_orientation(cls, screen: str):
         """
         @precond: is_connected(screen) = True
 
@@ -77,24 +131,45 @@ def get_current_orientation(screen: str):
         """
         stdout = execute(['xrandr', '--query', '--verbose'])
         # pattern = re.compile(rf'^{re.escape(screen)} .* \([^\)]+\) (\S+) \([^\)]+\) .*$', flags=re.MULTILINE)
-    pattern = re.compile(rf'^{re.escape(screen)} connected [^\(]+ \([^\)]+\) (\S+) \([^\)]+\) [^\(]+$', flags=re.MULTILINE)
+        pattern = re.compile(rf'^{re.escape(screen)} connected [^\(]+ \([^\)]+\) (\S+) \([^\)]+\) [^\(]+$',
+                             flags=re.MULTILINE)
         match = pattern.search(stdout)
         if match is None: raise Exception(f'Did not find screen {screen} in stdout:\n{stdout}')
         return match.group(1)
 
-
-def is_connected(screen: str):
+    @classmethod
+    def is_connected(cls, screen: str):
         """
         Example:
         - stdout includes line: eDP connected primary 2880x1620+0+0 (normal left inverted right x axis y axis) 344mm x 194mm
         - returns: True
         """
         stdout = execute(['xrandr'])
-    pattern = re.compile(rf'^({re.escape(screen)}\sconnected\s.*)$', flags=re.MULTILINE)
+        pattern = re.compile(rf'^({re.escape(screen)} connected .*)$', flags=re.MULTILINE)
         match = pattern.search(stdout)
         return match is not None
 
 
+class Xinput:
+    @classmethod
+    def map_to_output(cls, device: str, screen: str):
+        execute(['xinput', '--map-to-output', device, screen])
+
+    @classmethod
+    def get_device_tuples(cls) -> list[(int, str)]:
+        ids = cls.get_device_ids()
+        names = [execute(['xinput', 'list', '--name-only', id_]).strip() for id_ in ids]
+        return [(id_, name) for id_, name in zip(ids, names)]
+
+    @classmethod
+    def get_device_names(cls) -> list[str]:
+        return execute(['xinput', 'list', '--name-only']).strip().splitlines()
+
+    @classmethod
+    def get_device_ids(cls) -> list[int]:
+        return [int(id_) for id_ in execute(['xinput', 'list', '--id-only']).strip().splitlines()]
+
+
 def execute(command: list[str]) -> str:
     """
     :return: stdout of command execution