Adding a standalone calculator extension

docs/en/calculator.md

@@ -0,0 +1,40 @@
+# Calculator
+
+This extension adds a basic 4-function (+,-.*,/) calculator used with an attached display.
+
+## Adding the calculator extension
+
+You'll need to make sure you have a [display](Display.md) working first. Then import the calculator functions:
+
+`from kmk.extensions.calculator import Calc, InitCalc`
+
+Initialise the calculator, point it to the display, and tell it the layer you want your calculator functions associated with. For example, if your display is called "display" and your calculator buttons are going to be on layer 1, use:
+
+`InitCalc(display,1)`
+
+This will prepare a "calculator ready" screen on that layer.
+
+Now you need to create the keys for your calculator. Normally there will be 17 of these: one for each digit, one for each arithmetic function, one for the decimal point, one for the equals/enter button, one to clear, and one to send the current result to the connected computer. Each one needs to be pointed to the display and layer like the init function above:
+
+```
+KC_C0 = Calc("0",display,1)
+KC_C1 = Calc("1",display,1)
+KC_C2 = Calc("2",display,1)
+KC_C3 = Calc("3",display,1)
+KC_C4 = Calc("4",display,1)
+KC_C5 = Calc("5",display,1)
+KC_C6 = Calc("6",display,1)
+KC_C7 = Calc("7",display,1)
+KC_C8 = Calc("8",display,1)
+KC_C9 = Calc("9",display,1)
+KC_CEQ = Calc("=",display,1)
+KC_CADD = Calc("+",display,1)
+KC_CSUB = Calc("-",display,1)
+KC_CMUL = Calc("*",display,1)
+KC_CDIV = Calc("/",display,1)
+KC_CPT = Calc(".",display,1)
+KC_CCL = Calc("c",display,1) #clear
+KC_CSND = Calc("s",display,1) #send result
+```
+
+Now you can add these new keycodes to your keymap and you'll have a working desktop calculator!

docs/en/extensions.md

@@ -18,3 +18,4 @@ extensions are
   be treated the same as underglow.
 - [Status LED](extension_statusled.md): Indicates which layer you are on with an array of single leds.
 - [Stringy Keymaps](extension_stringy_keymaps): Enables referring to keys by `'NAME'` rather than `KC.NAME`
+- [Calculator](calculator.md): Adds a simple standalone 4-function calculator

kmk/extensions/calculator.py

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+from kmk.extensions.display import Display, TextEntry, ImageEntry
+
+from kmk.keys import Key
+
+from kmk.kmk_keyboard import KMKKeyboard
+from kmk.keys import KC
+
+import time
+
+from kmk.modules.macros import Macros
+
+macros=Macros()
+
+binary = {
+    '+': (lambda a, b: a+b, lambda a, b: a * (1+b/100)),
+    '-': (lambda a, b: a-b, lambda a, b: a * (1-b/100)),
+    '*': (lambda a, b: a*b, lambda a, b: a * (b/100)),
+    '/': (lambda a, b: a/b, lambda a, b: a / (b/100)),
+}
+
+equation = ""
+entry = ""
+number1 = None
+number2 = None
+trail = ["Ready."]
+op = None
+
+class Calc(Key):
+    def __init__(self, key, display, layer):
+        self.key = key
+        self.display = display
+        self.layer = layer
+        return
+
+    def on_press(self, keyboard, coord_int=None):
+        global entry
+        global number1
+        global number2
+        global trail
+        global op
+        global binary
+        global equation
+
+        if len(self.key) == 1 and self.key in "0123456789":
+            if equation == "":
+                number1 = None
+                number2 = None
+            entry = entry + self.key
+            equation = equation + self.key
+            self.display.entries = [TextEntry(equation,x=10,y=10,y_anchor="T",layer=self.layer)]
+
+        if self.key == "." and not "." in entry:
+            if entry == "":
+                entry = "0"
+            entry = entry + self.key
+            equation = equation + self.key
+            self.display.entries = [TextEntry(equation,x=10,y=10,y_anchor="T",layer=self.layer)]
+
+        if self.key == "c":
+            entry = ""
+            equation = ""
+            number1 = None
+            number2 = None
+            op = None
+            self.display.entries= [TextEntry("= Calculator Ready =",x=64,y=10,x_anchor="M",layer=self.layer)]
+
+        if self.key == "=" and op is not None:
+            if equation == "":
+                equation = format_number(str(number1)) + op + format_number(str(number2))
+            if entry is not "":
+                number2 = float(entry)
+                entry = ""
+            print("doing binary operation with " + str(number1) + ", " + op + ", " + str(number2))
+            self.do_binary_op()
+            self.display.entries=[TextEntry(equation,x=10,y=10,y_anchor="T",layer=self.layer),
+                             TextEntry(format_number(str(number1)),x=118,y=54,x_anchor="R",y_anchor="B",layer=self.layer)]
+            equation = ""
+
+        if self.key in binary:
+            self.display.entries=[TextEntry(equation,x=10,y=10,y_anchor="T",layer=self.layer)]
+            if entry is not "":
+                if number1 is None:
+                    number1 = float(entry)
+                    entry = ""
+                else:
+                    number2 = float(entry)
+                    entry = ""
+                    print("doing binary operation with " + str(number1) + ", " + op + ", " + str(number2))
+                    self.do_binary_op()
+            op = self.key
+            if equation == "":
+                equation = equation + format_number(str(number1))
+            equation = equation + self.key
+            self.display.entries=[TextEntry(equation,x=10,y=10,y_anchor="T",layer=self.layer)]
+
+        if self.key == "s" and number1 is not None:
+            keyboard.tap_key(KC.MACRO(format_number(str(number1))))
+
+        self.display.render(self.layer)
+
+    def on_release(self, keyboard, coord_int=None):
+        return
+
+    def do_binary_op(self):
+        global number1
+        global number2
+        global op
+        global binary
+        if op and number2 is not None:
+            number1 = binary[op][0](number1, number2)
+
+class InitCalc:
+    def __init__(self,display,layer):
+        display.entries += [TextEntry("= Calculator Ready =",x=64,y=10,x_anchor="M",layer=layer)]
+
+def format_number(num_str):
+    if "." in num_str:
+        parts = num_str.split(".")
+        integer_part = parts[0]
+        decimal_part = parts[1].rstrip("0")
+        if decimal_part:
+            return f"{integer_part}.{decimal_part}"
+        else:
+            return integer_part
+    return num_str