feat: Implement NTP sync function with garbage collection and improve schedule handling in web server

reduce ram usage bascically.
Fixes #22 (more garbage collection all it needed, but went further to try and cut more memory usage)
Fixes #21 (Just forgot to already marke this one as completed. Possibly in this commit too)

Scripts/web_server.py

@@ -636,6 +636,13 @@ class TempWebServer:
     def _get_status_page(self, sensors, ac_monitor, heater_monitor, schedule_monitor=None, show_success=False):
         """Generate HTML status page."""
         print("DEBUG: Generating status page...")
+        
+        # ===== FORCE GARBAGE COLLECTION BEFORE BIG ALLOCATION =====
+        import gc
+        gc.collect()
+        print("DEBUG: Memory freed, {} bytes available".format(gc.mem_free()))
+        # ===== END GARBAGE COLLECTION =====
+        
         try:
             # Get current temperatures (use cached values to avoid blocking)
             inside_temp = getattr(sensors.get('inside'), 'last_temp', None)
@@ -1453,18 +1460,45 @@ class TempWebServer:
         
         # Build mode buttons based on current state
         if config.get('schedule_enabled'):
+            # ===== NEW: Find active schedule =====
+            active_schedule_name = "None"
+            current_time = time.localtime()
+            current_minutes = current_time[3] * 60 + current_time[4]
+            
+            # Sort schedules by time and find the active one
+            sorted_schedules = []
+            for schedule in schedules:
+                if schedule.get('time'):
+                    try:
+                        time_parts = schedule['time'].split(':')
+                        schedule_minutes = int(time_parts[0]) * 60 + int(time_parts[1])
+                        sorted_schedules.append((schedule_minutes, schedule))
+                    except:
+                        pass
+            
+            sorted_schedules.sort()
+            
+            # Find most recent schedule that has passed
+            for schedule_minutes, schedule in sorted_schedules:
+                if current_minutes >= schedule_minutes:
+                    active_schedule_name = schedule.get('name', 'Unnamed')
+                else:
+                    break
+            
+            # If no schedule found (before first one), use last from yesterday
+            if active_schedule_name == "None" and sorted_schedules:
+                active_schedule_name = sorted_schedules[-1][1].get('name', 'Unnamed')
+            # ===== END: Find active schedule =====
+            
             return """
             <form method="POST" action="/schedule" style="margin: 20px 0;">
                 <div style="background: linear-gradient(135deg, #2ecc71, #27ae60); color: white; padding: 15px; border-radius: 10px; box-shadow: 0 4px 8px rgba(0,0,0,0.2);">
-                    <div style="font-weight: bold; font-size: 18px; margin-bottom: 10px;">✅ Automatic Mode</div>
+                    <div style="font-weight: bold; font-size: 18px; margin-bottom: 5px;">✅ Automatic Mode</div>
-                    <div style="font-size: 14px; margin-bottom: 15px;">Temperatures adjust based on schedule</div>
+                    <div style="font-size: 14px; opacity: 0.9; margin-bottom: 10px;">Currently running: <strong>{active_schedule}</strong></div>
-                    <div style="display: flex; gap: 10px; justify-content: center;">
+                    <div style="font-size: 13px; opacity: 0.8;">Temperatures adjust based on schedule</div>
-                        <button type="submit" name="mode_action" value="temporary_hold" style="padding: 10px 20px; background: #f39c12; color: white; border: none; border-radius: 6px; cursor: pointer; font-weight: bold;">⏸️ Temp Hold</button>
-                        <button type="submit" name="mode_action" value="permanent_hold" style="padding: 10px 20px; background: #e74c3c; color: white; border: none; border-radius: 6px; cursor: pointer; font-weight: bold;">🛑 Perm Hold</button>
-                    </div>
                 </div>
             </form>
-            """
+            """.format(active_schedule=active_schedule_name)
         elif config.get('permanent_hold', False):
             return """
             <form method="POST" action="/schedule" style="margin: 20px 0;">
@@ -1472,7 +1506,7 @@ class TempWebServer:
                     <div style="font-weight: bold; font-size: 18px; margin-bottom: 10px;">🛑 Permanent Hold</div>
                     <div style="font-size: 14px; margin-bottom: 15px;">Manual control only - Schedules disabled</div>
                     <div style="text-align: center;">
-                        <button type="submit" name="mode_action" value="resume" style="padding: 10px 20px; background: #2ecc71; color: white; border: none; border-radius: 6px; cursor: pointer; font-weight: bold;">▶️ Enable Schedules</button>
+                        <button type="submit" name="mode_action" value="resume" style="padding: 10px 20px; background: #2ecc71; color: white; border: none; border-radius: 6px; cursor: pointer; font-weight: bold;">▶️ Resume Scheduling</button>
                     </div>
                 </div>
             </form>
@@ -1483,9 +1517,8 @@ class TempWebServer:
                 <div style="background: linear-gradient(135deg, #f39c12, #e67e22); color: white; padding: 15px; border-radius: 10px; box-shadow: 0 4px 8px rgba(0,0,0,0.2);">
                     <div style="font-weight: bold; font-size: 18px; margin-bottom: 10px;">⏸️ Temporary Hold</div>
                     <div style="font-size: 14px; margin-bottom: 15px;">Manual override active</div>
-                    <div style="display: flex; gap: 10px; justify-content: center;">
+                    <div style="text-align: center;">
-                        <button type="submit" name="mode_action" value="resume" style="padding: 10px 20px; background: #2ecc71; color: white; border: none; border-radius: 6px; cursor: pointer; font-weight: bold;">▶️ Resume</button>
+                        <button type="submit" name="mode_action" value="resume" style="padding: 10px 20px; background: #2ecc71; color: white; border: none; border-radius: 6px; cursor: pointer; font-weight: bold;">▶️ Resume Scheduling</button>
-                        <button type="submit" name="mode_action" value="permanent_hold" style="padding: 10px 20px; background: #e74c3c; color: white; border: none; border-radius: 6px; cursor: pointer; font-weight: bold;">🛑 Perm Hold</button>
                     </div>
                 </div>
             </form>

main.py

@@ -4,9 +4,6 @@ import network # type: ignore
 import json
 import gc  # type: ignore # ADD THIS - for garbage collection
 import sys
-import socket  # type: ignore
-import struct  # type: ignore
-import ntptime  # type: ignore
 
 # Initialize pins (LED light onboard)
 led = Pin("LED", Pin.OUT)
@@ -33,6 +30,53 @@ from scripts.web_server import TempWebServer
 from scripts.scheduler import ScheduleMonitor  # NEW: Import scheduler for time-based temp changes
 from scripts.memory_check import check_memory_once  # Just the function
 
+# ===== NEW: NTP Sync Function (imports locally) =====
+def sync_ntp_time(timezone_offset):
+    """
+    Sync time with NTP server (imports modules locally to save RAM).
+    Returns True if successful, False otherwise.
+    """
+    try:
+        # Import ONLY when needed (freed by GC after function ends)
+        import socket  # type: ignore
+        import struct  # type: ignore
+        
+        NTP_DELTA = 2208988800
+        host = "pool.ntp.org"
+        NTP_QUERY = bytearray(48)
+        NTP_QUERY[0] = 0x1B
+        
+        # Create socket with timeout
+        s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
+        s.settimeout(3.0)  # 3-second timeout
+        
+        try:
+            addr = socket.getaddrinfo(host, 123)[0][-1]
+            s.sendto(NTP_QUERY, addr)
+            msg = s.recv(48)
+            val = struct.unpack("!I", msg[40:44])[0]
+            utc_timestamp = val - NTP_DELTA
+            
+            # Apply timezone offset
+            local_timestamp = utc_timestamp + (timezone_offset * 3600)
+            
+            # Set RTC with local time
+            tm = time.gmtime(local_timestamp)
+            RTC().datetime((tm[0], tm[1], tm[2], tm[6] + 1, tm[3], tm[4], tm[5], 0))
+            
+            return True
+            
+        finally:
+            s.close()
+            
+    except Exception as e:
+        print("NTP sync failed: {}".format(e))
+        return False
+    finally:
+        # Force garbage collection to free socket/struct modules
+        gc.collect()
+# ===== END: NTP Sync Function =====
+
 # ===== START: Configuration Loading =====
 # Load saved settings from config.json file on Pico
 def load_config():
@@ -161,46 +205,17 @@ if wifi and wifi.isconnected():
     web_server = TempWebServer(port=80)
     web_server.start()
 
-    # Attempt time sync with timeout (MicroPython compatible)
+    # ===== INITIAL NTP SYNC (using function) =====
     ntp_synced = False
-    try:  
+    try:
-        def time_with_timeout():
+        ntp_synced = sync_ntp_time(TIMEZONE_OFFSET)
-            """NTP time fetch with 3-second timeout."""
+        if ntp_synced:
-            NTP_DELTA = 2208988800
+            print("Time synced with NTP server (UTC{:+d})".format(TIMEZONE_OFFSET))
-            host = "pool.ntp.org"
+        else:
-            NTP_QUERY = bytearray(48)
+            print("Initial NTP sync failed, will retry in background...")
-            NTP_QUERY[0] = 0x1B
-            
-            # Create socket with timeout
-            s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
-            s.settimeout(3.0)  # 3-second timeout
-            
-            try:
-                addr = socket.getaddrinfo(host, 123)[0][-1]
-                s.sendto(NTP_QUERY, addr)
-                msg = s.recv(48)
-                s.close()
-                val = struct.unpack("!I", msg[40:44])[0]
-                return val - NTP_DELTA
-            finally:
-                s.close()
-        
-        # Get UTC time from NTP
-        utc_timestamp = time_with_timeout()
-        
-        # Apply timezone offset
-        local_timestamp = utc_timestamp + (TIMEZONE_OFFSET * 3600)
-        
-        # Set RTC with local time
-        tm = time.gmtime(local_timestamp)
-        RTC().datetime((tm[0], tm[1], tm[2], tm[6] + 1, tm[3], tm[4], tm[5], 0))
-        
-        ntp_synced = True
-        print("Time synced with NTP server (UTC{:+d})".format(TIMEZONE_OFFSET))
-        
     except Exception as e:
-        print("Initial NTP sync failed: {}".format(e))
+        print("Initial NTP sync error: {}".format(e))
-        print("Will retry in background...")
+    # ===== END: INITIAL NTP SYNC =====
     
 else:
     # WiFi connection failed
@@ -349,6 +364,7 @@ print("Press Ctrl+C to stop\n")
 # Add NTP retry flags (before main loop)
 retry_ntp_attempts = 0
 max_ntp_attempts = 5  # Try up to 5 times after initial failure
+last_ntp_sync = time.time()  # Track when we last synced
 
 # ===== START: Main Loop =====
 # Main monitoring loop (runs forever until Ctrl+C)
@@ -360,46 +376,27 @@ while True:
         # Web requests
         web_server.check_requests(sensors, ac_monitor, heater_monitor, schedule_monitor, config)
 
-        # Retry NTP sync every ~10s if not yet synced
+        # ===== RETRY NTP SYNC (if initial failed) =====
         if not ntp_synced and retry_ntp_attempts < max_ntp_attempts:
-            if retry_ntp_attempts == 0 or (time.time() % 10) < 1:
+            if time.time() % 10 < 1:  # Every 10 seconds
-                try:
+                if sync_ntp_time(TIMEZONE_OFFSET):
-                    import ntptime  # type: ignore
+                    ntp_synced = True
-                    import socket
+                    last_ntp_sync = time.time()
-                    import struct
+                    print("NTP sync succeeded on retry #{} (UTC{:+d})".format(retry_ntp_attempts + 1, TIMEZONE_OFFSET))
-                    
+                else:
-                    # Quick NTP sync with timeout
-                    NTP_DELTA = 2208988800
-                    host = "pool.ntp.org"
-                    NTP_QUERY = bytearray(48)
-                    NTP_QUERY[0] = 0x1B
-                    
-                    s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
-                    s.settimeout(3.0)  # 3-second timeout
-                    
-                    try:
-                        addr = socket.getaddrinfo(host, 123)[0][-1]
-                        s.sendto(NTP_QUERY, addr)
-                        msg = s.recv(48)
-                        val = struct.unpack("!I", msg[40:44])[0]
-                        utc_timestamp = val - NTP_DELTA
-                        
-                        # Apply timezone offset
-                        local_timestamp = utc_timestamp + (TIMEZONE_OFFSET * 3600)
-                        
-                        # Set RTC with local time
-                        tm = time.gmtime(local_timestamp)
-                        RTC().datetime((tm[0], tm[1], tm[2], tm[6] + 1, tm[3], tm[4], tm[5], 0))
-                        
-                        ntp_synced = True
-                        print("NTP sync succeeded on retry #{} (UTC{:+d})".format(retry_ntp_attempts + 1, TIMEZONE_OFFSET))
-                    finally:
-                        s.close()
-                        
-                except Exception as e:
                     retry_ntp_attempts += 1
-                    print("NTP retry {} failed: {}".format(retry_ntp_attempts, e))
+                    print("NTP retry {} failed".format(retry_ntp_attempts))
-
+        
+        # ===== PERIODIC RE-SYNC (every 24 hours) =====
+        # Re-sync once a day to correct clock drift
+        if ntp_synced and (time.time() - last_ntp_sync) > 86400:  # 24 hours in seconds
+            print("24-hour re-sync due...")
+            if sync_ntp_time(TIMEZONE_OFFSET):
+                last_ntp_sync = time.time()
+                print("Daily NTP re-sync successful")
+            else:
+                print("Daily NTP re-sync failed (will retry tomorrow)")
+        # ===== END: PERIODIC RE-SYNC =====
         # Enable garbage collection to free memory
         gc.collect()
         time.sleep(0.1)
@@ -424,6 +421,5 @@ while True:
         print("❌ Main loop error: {}".format(e))
         import sys
         sys.print_exception(e)
-        print("⚠️ Pausing 5 seconds before retrying...")
         time.sleep(5)  # Brief pause before retrying
 # ===== END: Main Loop =====