1 files changed, 153 insertions, 0 deletions
diff --git a/json_layer.py b/json_layer.py
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+++ b/json_layer.py
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+#
+# Read data in the json format from the serial connexion.
+# The json shall hold in a single line, and the following commands are
+# recognized :
+# {"layer": layer_name} : change the keyboard to the given layer
+# {"stack": layer_name} : stack a new layer on top on an existing one
+# {"get_layer"}
+#
+
+from usb_cdc import data
+import json
+
+from kmk.modules import Module
+from kmk.keys import Key, KC
+#from kmk.handlers.sequences import simple_key_sequence
+from kmk.modules.macros import Delay, Macros, Tap
+
+# This dictionnary is a sort of point of function.
+#
+# It gives a way to apply a specific function in the json
+#
+# There is mutually recursive calls between
+#   - operators
+#   - key_of_json
+#   - sequence
+#
+# I do not define it yet, only declare it.
+operators = {}
+
+def key_of_json(element, inside=False):
+    """ Create the key from the key name.
+        The value can be either a string or a list. If the parameter is a
+        string, the associated key will be returned, otherwise this will be the
+        chain of all of them.
+    """
+    if isinstance(element, int):
+        return element
+    if isinstance(element, str):
+        return KC[element]
+    if isinstance(element, list):
+        hd, *tl = element
+        key = key_of_json(hd)
+        if len(tl) != 0:
+            # Chainable key / recursive function
+            return key( key_of_json(tl) )
+        else:
+            return key
+    if isinstance(element, dict):
+        for key, value in element.items():
+            return operators[key](value)
+    pass
+
+def encode_macro(element):
+    """ Encode the result of the function key_of_json in order to build a macro
+        of this
+    """
+    key = key_of_json(element)
+    if isinstance(key, int):
+        return Delay(key)
+    elif isinstance(key, Key):
+        return Tap(key)
+    return key
+
+def sequence(element):
+    """ Convert a list of keys into a sequence of them.
+    """
+    # Convert each element in the list as Tap function
+    seq = list(map(encode_macro, element))
+    # Send the list as arguments to the function
+    return KC.MACRO(*seq)
+
+def no_release(element):
+    key = key_of_json(element)
+    return key(no_release=True)
+
+def no_press(element):
+    key = key_of_json(element)
+    return key(no_press=True)
+
+# Now I can define the dictionnary
+operators["key"]        = key_of_json
+operators["chain"]      = key_of_json
+operators["seq"]        = sequence
+operators["no_release"] = no_release
+operators["no_press"]   = no_press
+
+class Layer(object):
+    """ Layer as an object.
+        This class gives the property name in addition of the keymap list
+    """
+    def __init__(self, jdata):
+        self.load(jdata)
+
+    def load(self, json_data):
+        jdata = json.loads(json_data.strip())
+        for name, keys in jdata.items():
+            self.name = name
+            self.keys = list(map(key_of_json, keys))
+
+    def __getitem__(self, idx):
+        """ When the layer is indexed, return the keymap associated with
+        """
+        return self.keys[idx]
+
+    def __eq__(self, other):
+        """ Compare two layer by the name only
+        """
+        return self.name == other.name
+
+class JsonLayer(Module):
+
+    def during_bootup(self, keyboard):
+        try:
+            # Do not set any timeout, we check before reading a string if there
+            # is any content to read, but block to be sure to read everything.
+            data.timeout = None
+        except AttributeError:
+            pass
+
+    def before_matrix_scan(self, keyboard):
+        pass
+
+    def after_matrix_scan(self, keyboard):
+        pass
+
+    def process_key(self, keyboard, key, is_pressed, int_coord):
+        return key
+
+    def before_hid_send(self, keyboard):
+        # Serial.data isn't initialized.
+        if not data:
+            return
+
+        # Nothing to parse.
+        if data.in_waiting <= 0:
+            return
+        line = data.readline()
+        if not line:
+            return
+
+        try:
+            keyboard.keymap[0].load(line.decode())
+        except Exception as err:
+            print(err)
+
+    def after_hid_send(self, keyboard):
+        pass
+
+    def on_powersave_enable(self, keyboard):
+        pass
+
+    def on_powersave_disable(self, keyboard):
+        pass