Improve SD Card support

internal_filesystem/lib/mpos/sdcard.py

@@ -8,50 +8,110 @@ class SDCardManager:
         try:
             self._sdcard = machine.SDCard(spi_bus=spi_bus, cs=cs_pin)
             self._sdcard.info()
-            print("SD card initialized")
+            print("SD card initialized successfully")
         except Exception as e:
             print(f"ERROR: Failed to initialize SD card: {e}")
+            print("  - Possible causes: Invalid SPI configuration, SD card not inserted, faulty wiring, or firmware issue")
+            print(f"  - Check: SPI pins for the SPI bus, card insertion, VCC (3.3V/5V), GND")
+            print("  - Try: Hard reset ESP32, test with known-good SD card")
 
-    def mount(self, mount_point):
-        if not self._sdcard:
-            return False
+    def _try_mount(self, mount_point):
         try:
             os.mount(self._sdcard, mount_point)
-            print(f"Mounted at {mount_point}")
+            print(f"SD card mounted successfully at {mount_point}")
             return True
         except OSError as e:
-            print(f"Mount failed: {e}")
+            print(f"WARNING: Failed to mount SD card at {mount_point}: {e}")
+            print("  - Possible causes: Unformatted SD card (needs FAT32), corrupted filesystem, or card removed")
+            print(f"  - Check: SD card format, ensure card is inserted")
+            print("  - Try: Format card on PC, or proceed to auto-format if enabled")
             return False
 
-    def format_and_mount(self, mount_point):
-        if not self._sdcard:
-            return False
-        print("Formatting SD card...")
-        try:
-            os.umount(mount_point)
-        except:
-            pass
+    def _format(self, mount_point):
         try:
+            print(f"Attempting to format SD card for {mount_point}...")
+            try:
+                os.umount(mount_point)
+                print(f"  - Unmounted {mount_point} (if it was mounted)")
+            except OSError:
+                print(f"  - No prior mount found for {mount_point}, proceeding with format")
             vfs.VfsFat.mkfs(self._sdcard)
-            print("Formatted")
-            return self.mount(mount_point)
+            print("SD card formatted successfully as FAT32")
+            return True
         except OSError as e:
-            print(f"Format failed: {e}")
+            print(f"ERROR: Failed to format SD card: {e}")
+            print("  - Possible causes: SD card not inserted, write-protected, incompatible, or hardware error")
+            print(f"  - Check: Card insertion, write-protect switch, verify wiring of SPI bus.")
+            print("  - Try: Test with another SD card, reformat on PC, ensure VCC/GND correct")
+            return False
+
+    def mount_with_optional_format(self, mount_point):
+        if not self._sdcard:
+            print(f"ERROR: No SD card object initialized for mounting at {mount_point}")
+            print("  - Possible causes: SD card initialization failed in __init__")
+            print("  - Check: Review initialization errors above, verify SPI setup and hardware")
+            print("  - Try: Hard reset, check SPI pins and SD card")
+            return False
+
+        if not self._try_mount(mount_point):
+            print(f"INFO: Initial mount failed at {mount_point}, attempting to format...")
+            if self._format(mount_point):
+                if not self._try_mount(mount_point):
+                    print(f"ERROR: Failed to mount SD card at {mount_point} even after formatting")
+                    print("  - Possible causes: Persistent hardware issue, incompatible SD card, or firmware bug")
+                    print(f"  - Check: Wiring of SPI bus and card type.")
+                    print("  - Try: Hard reset, test with different SD card, reflash firmware")
+                    return False
+            else:
+                print(f"ERROR: Could not format SD card for {mount_point} - mount aborted")
+                print("  - See format error details above for troubleshooting")
+                return False
+
+        try:
+            contents = os.listdir(mount_point)
+            print(f"SD card contents at {mount_point}: {contents}")
+            return True
+        except OSError as e:
+            print(f"WARNING: Could not list SD card contents at {mount_point}: {e}")
+            print("  - Possible causes: Filesystem corruption, card removed, or VFS cache issue")
+            print(f"  - Check: Ensure card is inserted, verify mount with is_mounted('{mount_point}')")
+            print("  - Try: Unmount and remount, or reformat card")
             return False
 
     def is_mounted(self, mount_point):
         try:
-            return mount_point in os.listdir('/') and os.path.ismount(mount_point)
-        except:
+            mounted = mount_point in os.listdir('/') and not os.mkdir(f'{mount_point}/_tmp_test')
+            if mounted:
+                print(f"SD card is mounted at {mount_point}")
+                try:
+                    os.rmdir(f'{mount_point}/_tmp_test')
+                except:
+                    pass
+            else:
+                print(f"SD card is not mounted at {mount_point}")
+                print("  - Possible causes: Never mounted, unmounted manually, or card removed")
+                print(f"  - Try: Call mount_with_optional_format('{mount_point}')")
+            return mounted
+        except OSError as e:
+            print(f"WARNING: Failed to check mount status at {mount_point}: {e}")
+            print("  - Possible causes: Card removed, invalid mount point, or filesystem error")
+            print(f"  - Check: Ensure {mount_point} exists and card is inserted")
+            print("  - Try: Remount or reinsert card")
             return False
 
     def list(self, mount_point):
         try:
-            return os.listdir(mount_point)
-        except:
+            contents = os.listdir(mount_point)
+            print(f"SD card contents at {mount_point}: {contents}")
+            return contents
+        except OSError as e:
+            print(f"WARNING: Failed to list contents at {mount_point}: {e}")
+            print("  - Possible causes: SD card not mounted, removed, or corrupted filesystem")
+            print(f"  - Check: Run is_mounted('{mount_point}'), ensure card is inserted")
+            print("  - Try: Remount with mount_with_optional_format('{mount_point}')")
             return []
 
-# --- Global instance (singleton) ---
+# --- Singleton pattern ---
 _manager = None
 
 def init(spi_bus, cs_pin):
@@ -59,19 +119,34 @@ def init(spi_bus, cs_pin):
     global _manager
     if _manager is None:
         _manager = SDCardManager(spi_bus, cs_pin)
+    else:
+        print("WARNING: SDCardManager already initialized")
+        print("  - Use existing instance via get()")
     return _manager
 
 def get():
     """Get the global SD card manager instance."""
+    if _manager is None:
+        print("ERROR: SDCardManager not initialized")
+        print("  - Call init(spi_bus, cs_pin) first in boot.py or main.py")
     return _manager
 
-# Optional: convenience functions
 def mount(mount_point):
     mgr = get()
-    return mgr and mgr.mount(mount_point)
+    if mgr is None:
+        print("ERROR: Cannot mount - SDCardManager not initialized")
+        print("  - Call init(spi_bus, cs_pin) first")
+        return False
+    return mgr.mount(mount_point)
 
-def mount_with_format(mount_point):
+def mount_with_optional_format(mount_point):
     mgr = get()
-    if mgr and not mgr.mount(mount_point):
-        return mgr.format_and_mount(mount_point)
-    return mgr and mgr.is_mounted(mount_point)
+    if mgr is None:
+        print("ERROR: Cannot mount with format - SDCardManager not initialized")
+        print("  - Call init(spi_bus, cs_pin) first")
+        return False
+    success = mgr.mount_with_optional_format(mount_point)
+    if not success:
+        print(f"ERROR: mount_with_format('{mount_point}') failed")
+        print("  - See detailed errors above for mount or format issues")
+    return success