Add ACController class for managing AC unit operation with safety timers

Scripts/air_conditioning.py

@@ -0,0 +1,68 @@
+from machine import Pin
+import time
+
+class ACController:
+    """Control AC unit via opto-coupler relay."""
+    def __init__(self, relay_pin=15, min_run_time=300, min_off_time=180):
+        """
+        relay_pin: GPIO pin connected to opto-coupler input
+        min_run_time: Minimum seconds AC must run before turning off (prevent short cycling)
+        min_off_time: Minimum seconds AC must be off before turning on (compressor protection)
+        """
+        self.relay = Pin(relay_pin, Pin.OUT)
+        self.relay.off()  # Start with AC off (relay normally open)
+        
+        self.min_run_time = min_run_time
+        self.min_off_time = min_off_time
+        
+        self.is_on = False
+        self.last_state_change = time.ticks_ms()
+    
+    def turn_on(self):
+        """Turn AC on if minimum off time has elapsed."""
+        if self.is_on:
+            return True  # Already on
+        
+        now = time.ticks_ms()
+        time_since_change = time.ticks_diff(now, self.last_state_change) / 1000
+        
+        if time_since_change < self.min_off_time:
+            remaining = int(self.min_off_time - time_since_change)
+            print(f"AC cooldown: {remaining}s remaining before can turn on")
+            return False
+        
+        self.relay.on()
+        self.is_on = True
+        self.last_state_change = now
+        print("AC turned ON")
+        return True
+    
+    def turn_off(self):
+        """Turn AC off if minimum run time has elapsed."""
+        if not self.is_on:
+            return True  # Already off
+        
+        now = time.ticks_ms()
+        time_since_change = time.ticks_diff(now, self.last_state_change) / 1000
+        
+        if time_since_change < self.min_run_time:
+            remaining = int(self.min_run_time - time_since_change)
+            print(f"AC minimum runtime: {remaining}s remaining before can turn off")
+            return False
+        
+        self.relay.off()
+        self.is_on = False
+        self.last_state_change = now
+        print("AC turned OFF")
+        return True
+    
+    def get_state(self):
+        """Return current AC state."""
+        return self.is_on
+    
+    def force_off(self):
+        """Emergency shut off (bypasses timers)."""
+        self.relay.off()
+        self.is_on = False
+        self.last_state_change = time.ticks_ms()
+        print("AC FORCE OFF")