Route DisplayWrite throughout MVC

Author: brentru

src/Wippersnapper.cpp

@@ -1688,6 +1688,17 @@ bool cbDecodeDisplayMsg(pb_istream_t *stream, const pb_field_t *field,
         WS._displayController->Handle_Display_AddOrReplace(&msgAddReq);
     // TODO: Add response handling and publishing here, for now it always
     // returns true and doesnt publish back to the broker
+  } else if (field->tag ==
+             wippersnapper_signal_v1_DisplayRequest_display_write_tag) {
+    // Decode message into a DisplayAddRequest
+    wippersnapper_display_v1_DisplayWrite msgWrite =
+        wippersnapper_display_v1_DisplayWrite_init_zero;
+    if (!ws_pb_decode(stream, wippersnapper_display_v1_DisplayWrite_fields,
+                      &msgWrite)) {
+      WS_DEBUG_PRINTLN("ERROR: Failure decoding DisplayWrite message!");
+      return false;
+    }
+    WS._displayController->Handle_Display_Write(&msgWrite);
   }
   return true;
 }

src/components/display/controller.cpp

@@ -84,4 +84,32 @@ bool DisplayController::Handle_Display_Remove(
   }
   WS_DEBUG_PRINTLN("[display] Could not remove display, not found!");
   return false;
+}
+
+/*!
+    @brief  Handles a Display_Write message.
+    @param  msgWrite
+            Pointer to a DisplayWrite message structure.
+    @return True if the display write was successful, false otherwise.
+*/
+bool DisplayController::Handle_Display_Write(
+    wippersnapper_display_v1_DisplayWrite *msgWrite) {
+  // Get the driver instance for the display
+  DisplayHardware *display = nullptr;
+  for (auto &hw_instance : _hw_instances) {
+    if (strcmp(hw_instance->getName(), msgWrite->name) == 0) {
+      display = hw_instance;
+      break;
+    }
+  }
+
+  // Early-out if display not found
+  if (!display) {
+    WS_DEBUG_PRINTLN("[display] Failed to write, driver not found!");
+    return false;
+  }
+
+  // Write the message to the display
+  display->writeMessage(msgWrite->message);
+  return true;
 }

src/components/display/controller.h

@@ -34,7 +34,8 @@ class DisplayController {
   bool Handle_Display_AddOrReplace(
       wippersnapper_display_v1_DisplayAddOrReplace *msgAdd);
   bool Handle_Display_Remove(wippersnapper_display_v1_DisplayRemove *msgRemove);
-  // bool Handle_Display_Write(...);
+  bool Handle_Display_Write(wippersnapper_display_v1_DisplayWrite *msgWrite);
+
 private:
   std::vector<DisplayHardware *>
       _hw_instances; ///< Holds pointers to DisplayHardware instances

src/components/display/drivers/dispDrvBase.h

@@ -31,15 +31,17 @@ class dispDrvBase {
     // Destructor implementation (if we need one)
   };
 
-  // Virtual function to be implemented by derived classes
   virtual bool begin(thinkinkmode_t mode, bool reset = true);
 
+  virtual void writeMessage(const char *message) = 0;
+
 protected:
   int16_t _pin_dc;
   int16_t _pin_rst;
   int16_t _pin_cs;
   int16_t _pin_busy;
   int16_t _pin_sram_cs; // for optional EPD SRAM chip select
+  uint8_t _text_sz = 1; ///< Text size for display messages
 };
 
 #endif // WS_DISP_DRV_BASE_H

src/components/display/drivers/dispDrvThinkInkGrayscale4Eaamfgn.h

@@ -41,9 +41,55 @@ class drvDispThinkInkGrayscale4Eaamfgn : public dispDrvBase {
     // Clear the display buffer
     _display->clearBuffer();
     _display->display();
+
     return true;
   }
 
+  virtual void writeMessage(const char *message) override {
+    if (_display == nullptr)
+      return;
+
+    // Start with a fresh display buffer
+    // and settings
+    int16_t y_idx = 0;
+    _display->clearDisplay();
+    _display->setTextSize(_text_sz);
+    _display->setTextColor(EPD_BLACK);
+    _display->setCursor(0, y_idx);
+    _display->display();
+
+    // Calculate the line height based on the text size (NOTE: base height is
+    // 8px)
+    int16_t line_height = 8 * _text_sz;
+    uint16_t c_idx = 0;
+    size_t msg_size = strlen(message);
+    for (size_t i = 0; i < msg_size && c_idx < msg_size; i++) {
+      if (message[i] == '\\' && i + 1 < msg_size &&
+          (message[i + 1] == 'n' || message[i + 1] == 'r')) {
+        // Handle \r\n sequence as a single newline
+        if (message[i + 1] == 'r' && i + 3 < msg_size &&
+            message[i + 2] == '\\' && message[i + 3] == 'n') {
+          // Skip to the next line
+          y_idx += line_height;
+          _display->setCursor(0, y_idx);
+          i += 3;
+        } else if (message[i + 1] == 'n') {
+          // Skip to the next line
+          y_idx += line_height;
+          _display->setCursor(0, y_idx);
+          i++;
+        }
+      } else if (message[i] == 0xC2 && message[i + 1] == 0xB0) {
+        _display->write(char(248));
+        _display->display();
+        i++;
+      } else {
+        _display->print(message[i]);
+        _display->display();
+      }
+    }
+  }
+
 private:
   ThinkInk_290_Grayscale4_EAAMFGN *_display;
 };

src/components/display/hardware.cpp

@@ -105,13 +105,6 @@ bool DisplayHardware::beginEPD(
     return false;
   }
 
-  // Validate panel type
-  if (config->panel ==
-      wippersnapper_display_v1_EPDThinkInkPanel_EPD_THINK_INK_PANEL_UNSPECIFIED) {
-    WS_DEBUG_PRINTLN("[display] Unsupported EPD panel type!");
-    return false; // Unsupported panel type
-  }
-
   // Validate mode is a correct EPD mode
   if (config->mode == wippersnapper_display_v1_EPDMode_EPD_MODE_UNSPECIFIED) {
     WS_DEBUG_PRINTLN("[display] Unsupported EPD mode!");
@@ -168,17 +161,24 @@ bool DisplayHardware::beginEPD(
 
   if (!_disp_drv_base->begin(epd_mode)) {
     WS_DEBUG_PRINTLN("[display] Failed to begin display driver!");
-    delete _disp_drv_base; // Clean up if initialization failed
+    delete _disp_drv_base;
     _disp_drv_base = nullptr;
-    return false; // Failed to begin display driver
+    return false;
   }
 
   return true; // Configuration successful
 }
 
-
 /*!
     @brief  Gets the name of the display hardware instance.
     @return The name of the display hardware instance.
 */
 const char *DisplayHardware::getName() { return _name; }
+
+void DisplayHardware::writeMessage(const char *message) {
+  if (_disp_drv_base) {
+    _disp_drv_base->writeMessage(message);
+  } else {
+    WS_DEBUG_PRINTLN("[display] No display driver initialized!");
+  }
+}

src/components/display/hardware.h

@@ -44,13 +44,14 @@ class DisplayHardware {
 
   //
   // API for Adafruit_GFX that abstracts hardware functionality
-  // NOTE: These methods are meant to be implemented within dispDrvBase and exposed within dispDrv driver instances
+  // NOTE: These methods are meant to be implemented within dispDrvBase and
+  // exposed within dispDrv driver instances
   //
-  // TODO
+  void writeMessage(const char *message);
 
 private:
   const char *_name; ///< Identifies the hardware instance
   wippersnapper_display_v1_DisplayType _type; ///< Display type
-  dispDrvBase *_disp_drv_base = nullptr; ///< Base display driver
+  dispDrvBase *_disp_drv_base = nullptr;      ///< Base display driver
 };
 #endif // WS_DISPLAY_HARDWARE_H