From 8c5c39dbe3685ef67f5c779925b7a16afa3e4e04 Mon Sep 17 00:00:00 2001
From: cottongin <cottongin@users.noreply.github.com>
Date: Mon, 3 Aug 2026 10:56:55 -0400
Subject: [PATCH] feat: display manager for e-ink framebuffer output and text
 messages

Co-authored-by: Cursor <cursoragent@cursor.com>
---
 src/display_manager.cpp | 122 ++++++++++++++++++++++++++++++++++++++++
 src/display_manager.h   |  25 ++++++++
 2 files changed, 147 insertions(+)
 create mode 100644 src/display_manager.cpp
 create mode 100644 src/display_manager.h

diff --git a/src/display_manager.cpp b/src/display_manager.cpp
new file mode 100644
index 0000000..9da5fae
--- /dev/null
+++ b/src/display_manager.cpp
@@ -0,0 +1,122 @@
+#include "display_manager.h"
+#include "power_manager.h"
+#include <M5Unified.h>
+
+// Map 6-color palette indices to RGB565 for M5GFX
+static const uint16_t PALETTE_565[6] = {
+    0x0000,  // Black
+    0xFFFF,  // White
+    0xF800,  // Red (approximate)
+    0x07E0,  // Green (approximate)
+    0x001F,  // Blue (approximate)
+    0xFFE0   // Yellow (approximate)
+};
+
+void DisplayManager::begin(PowerManager& power) {
+    _power = &power;
+    _display = &M5.Display;
+
+    // Set rotation for landscape (device physically rotated)
+    // Rotation value depends on how the display is mounted — likely 1 or 3
+    _display->setRotation(1);
+
+    Serial.printf("[display] Initialized: %dx%d, rotation=%d\n",
+                  _display->width(), _display->height(), _display->getRotation());
+
+    showMessage("Immich Frame", "Starting up...");
+}
+
+void DisplayManager::showImage(const ProcessedImage& img) {
+    if (!img.valid || img.framebuffer == nullptr) {
+        Serial.println("[display] Invalid image — skipping");
+        return;
+    }
+
+    _power->enableEPDPower();
+
+    Serial.println("[display] Writing framebuffer to e-ink...");
+    unsigned long start = millis();
+
+    // Write pixel by pixel using palette-mapped colors
+    _display->startWrite();
+    for (uint16_t y = 0; y < img.height; y++) {
+        for (uint16_t x = 0; x < img.width; x++) {
+            uint8_t colorIdx = img.framebuffer[y * img.width + x];
+            _display->writePixel(x, y, PALETTE_565[colorIdx]);
+        }
+    }
+    _display->endWrite();
+
+    triggerRefresh();
+
+    unsigned long elapsed = millis() - start;
+    Serial.printf("[display] Refresh complete in %lu ms\n", elapsed);
+
+    _power->disableEPDPower();
+}
+
+void DisplayManager::showMessage(const char* title, const char* body) {
+    _power->enableEPDPower();
+
+    _display->fillScreen(TFT_WHITE);
+    _display->setTextColor(TFT_BLACK);
+    _display->setTextDatum(middle_center);
+    _display->setTextSize(2);
+    _display->drawString(title, DISPLAY_WIDTH / 2, DISPLAY_HEIGHT / 2 - 30);
+    _display->setTextSize(1);
+    _display->drawString(body, DISPLAY_WIDTH / 2, DISPLAY_HEIGHT / 2 + 20);
+
+    triggerRefresh();
+    _power->disableEPDPower();
+}
+
+void DisplayManager::showMetadata(const AssetInfo& info, uint8_t metaFlags, MetaPosition pos) {
+    if (metaFlags == 0) return;  // No metadata to show
+
+    // Build metadata string
+    String metaText = "";
+
+    if ((metaFlags & META_DATE) && info.dateTime.length() > 0) {
+        // Extract just the date portion (YYYY-MM-DD)
+        metaText += info.dateTime.substring(0, 10);
+    }
+    if ((metaFlags & META_LOCATION) && info.city.length() > 0) {
+        if (metaText.length() > 0) metaText += "  |  ";
+        metaText += info.city;
+    }
+    if ((metaFlags & META_PEOPLE) && !info.people.empty()) {
+        if (metaText.length() > 0) metaText += "  |  ";
+        for (size_t i = 0; i < info.people.size(); i++) {
+            if (i > 0) metaText += ", ";
+            metaText += info.people[i];
+        }
+    }
+    if ((metaFlags & META_ALBUM)) {
+        // Album name would need to be passed separately — skip for now
+    }
+    if ((metaFlags & META_CAMERA) && info.camera.length() > 0) {
+        if (metaText.length() > 0) metaText += "  |  ";
+        metaText += info.camera;
+    }
+
+    if (metaText.length() == 0) return;
+
+    // Draw semi-transparent bar with text
+    uint16_t barY = (pos == MetaPosition::Top) ? 0 : (DISPLAY_HEIGHT - 30);
+    _display->fillRect(0, barY, DISPLAY_WIDTH, 30, TFT_BLACK);
+    _display->setTextColor(TFT_WHITE);
+    _display->setTextDatum(middle_center);
+    _display->setTextSize(1);
+    _display->drawString(metaText.c_str(), DISPLAY_WIDTH / 2, barY + 15);
+}
+
+void DisplayManager::triggerRefresh() {
+    // M5GFX handles e-ink refresh internally when using the EPD panel driver
+    // The display() call triggers the actual e-ink refresh cycle (10-20s)
+    _display->display();
+}
+
+uint16_t DisplayManager::paletteToColor565(uint8_t index) {
+    if (index >= DISPLAY_COLORS) return 0;
+    return PALETTE_565[index];
+}
diff --git a/src/display_manager.h b/src/display_manager.h
new file mode 100644
index 0000000..028e39e
--- /dev/null
+++ b/src/display_manager.h
@@ -0,0 +1,25 @@
+#pragma once
+
+#include <Arduino.h>
+#include <M5GFX.h>
+#include "config.h"
+#include "image_pipeline.h"
+#include "immich_client.h"
+#include "settings.h"
+
+class PowerManager;
+
+class DisplayManager {
+public:
+    void begin(PowerManager& power);
+    void showImage(const ProcessedImage& img);
+    void showMessage(const char* title, const char* body);
+    void showMetadata(const AssetInfo& info, uint8_t metaFlags, MetaPosition pos);
+
+private:
+    PowerManager* _power = nullptr;
+    M5GFX* _display = nullptr;
+
+    void triggerRefresh();
+    uint16_t paletteToColor565(uint8_t index);
+};