Change qr library to properly support utf8 characters

lib/QRCode/library.properties

@@ -0,0 +1,10 @@
+name=QRCode
+version=1.8.0
+author=Nayuki
+maintainer=Nayuki
+sentence=QR Code generator library (C port)
+paragraph=High-quality QR Code generator library with ECI support. Ported from https://github.com/nayuki/QR-Code-generator
+category=Other
+url=https://github.com/nayuki/QR-Code-generator
+architectures=*
+includes=qrcodegen.h

lib/QRCode/src/qrcodegen.h

@@ -0,0 +1,385 @@
+/* 
+ * QR Code generator library (C)
+ * 
+ * Copyright (c) Project Nayuki. (MIT License)
+ * https://www.nayuki.io/page/qr-code-generator-library
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ * - The above copyright notice and this permission notice shall be included in
+ *   all copies or substantial portions of the Software.
+ * - The Software is provided "as is", without warranty of any kind, express or
+ *   implied, including but not limited to the warranties of merchantability,
+ *   fitness for a particular purpose and noninfringement. In no event shall the
+ *   authors or copyright holders be liable for any claim, damages or other
+ *   liability, whether in an action of contract, tort or otherwise, arising from,
+ *   out of or in connection with the Software or the use or other dealings in the
+ *   Software.
+ */
+
+#pragma once
+
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+
+/* 
+ * This library creates QR Code symbols, which is a type of two-dimension barcode.
+ * Invented by Denso Wave and described in the ISO/IEC 18004 standard.
+ * A QR Code structure is an immutable square grid of dark and light cells.
+ * The library provides functions to create a QR Code from text or binary data.
+ * The library covers the QR Code Model 2 specification, supporting all versions (sizes)
+ * from 1 to 40, all 4 error correction levels, and 4 character encoding modes.
+ * 
+ * Ways to create a QR Code object:
+ * - High level: Take the payload data and call qrcodegen_encodeText() or qrcodegen_encodeBinary().
+ * - Low level: Custom-make the list of segments and call
+ *   qrcodegen_encodeSegments() or qrcodegen_encodeSegmentsAdvanced().
+ * (Note that all ways require supplying the desired error correction level and various byte buffers.)
+ */
+
+
+/*---- Enum and struct types----*/
+
+/* 
+ * The error correction level in a QR Code symbol.
+ */
+enum qrcodegen_Ecc {
+	// Must be declared in ascending order of error protection
+	// so that an internal qrcodegen function works properly
+	qrcodegen_Ecc_LOW = 0 ,  // The QR Code can tolerate about  7% erroneous codewords
+	qrcodegen_Ecc_MEDIUM  ,  // The QR Code can tolerate about 15% erroneous codewords
+	qrcodegen_Ecc_QUARTILE,  // The QR Code can tolerate about 25% erroneous codewords
+	qrcodegen_Ecc_HIGH    ,  // The QR Code can tolerate about 30% erroneous codewords
+};
+
+
+/* 
+ * The mask pattern used in a QR Code symbol.
+ */
+enum qrcodegen_Mask {
+	// A special value to tell the QR Code encoder to
+	// automatically select an appropriate mask pattern
+	qrcodegen_Mask_AUTO = -1,
+	// The eight actual mask patterns
+	qrcodegen_Mask_0 = 0,
+	qrcodegen_Mask_1,
+	qrcodegen_Mask_2,
+	qrcodegen_Mask_3,
+	qrcodegen_Mask_4,
+	qrcodegen_Mask_5,
+	qrcodegen_Mask_6,
+	qrcodegen_Mask_7,
+};
+
+
+/* 
+ * Describes how a segment's data bits are interpreted.
+ */
+enum qrcodegen_Mode {
+	qrcodegen_Mode_NUMERIC      = 0x1,
+	qrcodegen_Mode_ALPHANUMERIC = 0x2,
+	qrcodegen_Mode_BYTE         = 0x4,
+	qrcodegen_Mode_KANJI        = 0x8,
+	qrcodegen_Mode_ECI          = 0x7,
+};
+
+
+/* 
+ * A segment of character/binary/control data in a QR Code symbol.
+ * The mid-level way to create a segment is to take the payload data
+ * and call a factory function such as qrcodegen_makeNumeric().
+ * The low-level way to create a segment is to custom-make the bit buffer
+ * and initialize a qrcodegen_Segment struct with appropriate values.
+ * Even in the most favorable conditions, a QR Code can only hold 7089 characters of data.
+ * Any segment longer than this is meaningless for the purpose of generating QR Codes.
+ * Moreover, the maximum allowed bit length is 32767 because
+ * the largest QR Code (version 40) has 31329 modules.
+ */
+struct qrcodegen_Segment {
+	// The mode indicator of this segment.
+	enum qrcodegen_Mode mode;
+	
+	// The length of this segment's unencoded data. Measured in characters for
+	// numeric/alphanumeric/kanji mode, bytes for byte mode, and 0 for ECI mode.
+	// Always zero or positive. Not the same as the data's bit length.
+	int numChars;
+	
+	// The data bits of this segment, packed in bitwise big endian.
+	// Can be null if the bit length is zero.
+	uint8_t *data;
+	
+	// The number of valid data bits used in the buffer. Requires
+	// 0 <= bitLength <= 32767, and bitLength <= (capacity of data array) * 8.
+	// The character count (numChars) must agree with the mode and the bit buffer length.
+	int bitLength;
+};
+
+
+
+/*---- Macro constants and functions ----*/
+
+#define qrcodegen_VERSION_MIN   1  // The minimum version number supported in the QR Code Model 2 standard
+#define qrcodegen_VERSION_MAX  40  // The maximum version number supported in the QR Code Model 2 standard
+
+// Calculates the number of bytes needed to store any QR Code up to and including the given version number,
+// as a compile-time constant. For example, 'uint8_t buffer[qrcodegen_BUFFER_LEN_FOR_VERSION(25)];'
+// can store any single QR Code from version 1 to 25 (inclusive). The result fits in an int (or int16).
+// Requires qrcodegen_VERSION_MIN <= n <= qrcodegen_VERSION_MAX.
+#define qrcodegen_BUFFER_LEN_FOR_VERSION(n)  ((((n) * 4 + 17) * ((n) * 4 + 17) + 7) / 8 + 1)
+
+// The worst-case number of bytes needed to store one QR Code, up to and including
+// version 40. This value equals 3918, which is just under 4 kilobytes.
+// Use this more convenient value to avoid calculating tighter memory bounds for buffers.
+#define qrcodegen_BUFFER_LEN_MAX  qrcodegen_BUFFER_LEN_FOR_VERSION(qrcodegen_VERSION_MAX)
+
+
+
+/*---- Functions (high level) to generate QR Codes ----*/
+
+/* 
+ * Encodes the given text string to a QR Code, returning true if successful.
+ * If the data is too long to fit in any version in the given range
+ * at the given ECC level, then false is returned.
+ * 
+ * The input text must be encoded in UTF-8 and contain no NULs.
+ * Requires 1 <= minVersion <= maxVersion <= 40.
+ * 
+ * The smallest possible QR Code version within the given range is automatically
+ * chosen for the output. Iff boostEcl is true, then the ECC level of the result
+ * may be higher than the ecl argument if it can be done without increasing the
+ * version. The mask is either between qrcodegen_Mask_0 to 7 to force that mask, or
+ * qrcodegen_Mask_AUTO to automatically choose an appropriate mask (which may be slow).
+ * 
+ * About the arrays, letting len = qrcodegen_BUFFER_LEN_FOR_VERSION(maxVersion):
+ * - Before calling the function:
+ *   - The array ranges tempBuffer[0 : len] and qrcode[0 : len] must allow
+ *     reading and writing; hence each array must have a length of at least len.
+ *   - The two ranges must not overlap (aliasing).
+ *   - The initial state of both ranges can be uninitialized
+ *     because the function always writes before reading.
+ * - After the function returns:
+ *   - Both ranges have no guarantee on which elements are initialized and what values are stored.
+ *   - tempBuffer contains no useful data and should be treated as entirely uninitialized.
+ *   - If successful, qrcode can be passed into qrcodegen_getSize() and qrcodegen_getModule().
+ * 
+ * If successful, the resulting QR Code may use numeric,
+ * alphanumeric, or byte mode to encode the text.
+ * 
+ * In the most optimistic case, a QR Code at version 40 with low ECC
+ * can hold any UTF-8 string up to 2953 bytes, or any alphanumeric string
+ * up to 4296 characters, or any digit string up to 7089 characters.
+ * These numbers represent the hard upper limit of the QR Code standard.
+ * 
+ * Please consult the QR Code specification for information on
+ * data capacities per version, ECC level, and text encoding mode.
+ */
+bool qrcodegen_encodeText(const char *text, uint8_t tempBuffer[], uint8_t qrcode[],
+	enum qrcodegen_Ecc ecl, int minVersion, int maxVersion, enum qrcodegen_Mask mask, bool boostEcl);
+
+
+/* 
+ * Encodes the given binary data to a QR Code, returning true if successful.
+ * If the data is too long to fit in any version in the given range
+ * at the given ECC level, then false is returned.
+ * 
+ * Requires 1 <= minVersion <= maxVersion <= 40.
+ * 
+ * The smallest possible QR Code version within the given range is automatically
+ * chosen for the output. Iff boostEcl is true, then the ECC level of the result
+ * may be higher than the ecl argument if it can be done without increasing the
+ * version. The mask is either between qrcodegen_Mask_0 to 7 to force that mask, or
+ * qrcodegen_Mask_AUTO to automatically choose an appropriate mask (which may be slow).
+ * 
+ * About the arrays, letting len = qrcodegen_BUFFER_LEN_FOR_VERSION(maxVersion):
+ * - Before calling the function:
+ *   - The array ranges dataAndTemp[0 : len] and qrcode[0 : len] must allow
+ *     reading and writing; hence each array must have a length of at least len.
+ *   - The two ranges must not overlap (aliasing).
+ *   - The input array range dataAndTemp[0 : dataLen] should normally be
+ *     valid UTF-8 text, but is not required by the QR Code standard.
+ *   - The initial state of dataAndTemp[dataLen : len] and qrcode[0 : len]
+ *     can be uninitialized because the function always writes before reading.
+ * - After the function returns:
+ *   - Both ranges have no guarantee on which elements are initialized and what values are stored.
+ *   - dataAndTemp contains no useful data and should be treated as entirely uninitialized.
+ *   - If successful, qrcode can be passed into qrcodegen_getSize() and qrcodegen_getModule().
+ * 
+ * If successful, the resulting QR Code will use byte mode to encode the data.
+ * 
+ * In the most optimistic case, a QR Code at version 40 with low ECC can hold any byte
+ * sequence up to length 2953. This is the hard upper limit of the QR Code standard.
+ * 
+ * Please consult the QR Code specification for information on
+ * data capacities per version, ECC level, and text encoding mode.
+ */
+bool qrcodegen_encodeBinary(uint8_t dataAndTemp[], size_t dataLen, uint8_t qrcode[],
+	enum qrcodegen_Ecc ecl, int minVersion, int maxVersion, enum qrcodegen_Mask mask, bool boostEcl);
+
+
+/*---- Functions (low level) to generate QR Codes ----*/
+
+/* 
+ * Encodes the given segments to a QR Code, returning true if successful.
+ * If the data is too long to fit in any version at the given ECC level,
+ * then false is returned.
+ * 
+ * The smallest possible QR Code version is automatically chosen for
+ * the output. The ECC level of the result may be higher than the
+ * ecl argument if it can be done without increasing the version.
+ * 
+ * About the byte arrays, letting len = qrcodegen_BUFFER_LEN_FOR_VERSION(qrcodegen_VERSION_MAX):
+ * - Before calling the function:
+ *   - The array ranges tempBuffer[0 : len] and qrcode[0 : len] must allow
+ *     reading and writing; hence each array must have a length of at least len.
+ *   - The two ranges must not overlap (aliasing).
+ *   - The initial state of both ranges can be uninitialized
+ *     because the function always writes before reading.
+ *   - The input array segs can contain segments whose data buffers overlap with tempBuffer.
+ * - After the function returns:
+ *   - Both ranges have no guarantee on which elements are initialized and what values are stored.
+ *   - tempBuffer contains no useful data and should be treated as entirely uninitialized.
+ *   - Any segment whose data buffer overlaps with tempBuffer[0 : len]
+ *     must be treated as having invalid values in that array.
+ *   - If successful, qrcode can be passed into qrcodegen_getSize() and qrcodegen_getModule().
+ * 
+ * Please consult the QR Code specification for information on
+ * data capacities per version, ECC level, and text encoding mode.
+ * 
+ * This function allows the user to create a custom sequence of segments that switches
+ * between modes (such as alphanumeric and byte) to encode text in less space.
+ * This is a low-level API; the high-level API is qrcodegen_encodeText() and qrcodegen_encodeBinary().
+ */
+bool qrcodegen_encodeSegments(const struct qrcodegen_Segment segs[], size_t len,
+	enum qrcodegen_Ecc ecl, uint8_t tempBuffer[], uint8_t qrcode[]);
+
+
+/* 
+ * Encodes the given segments to a QR Code, returning true if successful.
+ * If the data is too long to fit in any version in the given range
+ * at the given ECC level, then false is returned.
+ * 
+ * Requires 1 <= minVersion <= maxVersion <= 40.
+ * 
+ * The smallest possible QR Code version within the given range is automatically
+ * chosen for the output. Iff boostEcl is true, then the ECC level of the result
+ * may be higher than the ecl argument if it can be done without increasing the
+ * version. The mask is either between qrcodegen_Mask_0 to 7 to force that mask, or
+ * qrcodegen_Mask_AUTO to automatically choose an appropriate mask (which may be slow).
+ * 
+ * About the byte arrays, letting len = qrcodegen_BUFFER_LEN_FOR_VERSION(qrcodegen_VERSION_MAX):
+ * - Before calling the function:
+ *   - The array ranges tempBuffer[0 : len] and qrcode[0 : len] must allow
+ *     reading and writing; hence each array must have a length of at least len.
+ *   - The two ranges must not overlap (aliasing).
+ *   - The initial state of both ranges can be uninitialized
+ *     because the function always writes before reading.
+ *   - The input array segs can contain segments whose data buffers overlap with tempBuffer.
+ * - After the function returns:
+ *   - Both ranges have no guarantee on which elements are initialized and what values are stored.
+ *   - tempBuffer contains no useful data and should be treated as entirely uninitialized.
+ *   - Any segment whose data buffer overlaps with tempBuffer[0 : len]
+ *     must be treated as having invalid values in that array.
+ *   - If successful, qrcode can be passed into qrcodegen_getSize() and qrcodegen_getModule().
+ * 
+ * Please consult the QR Code specification for information on
+ * data capacities per version, ECC level, and text encoding mode.
+ * 
+ * This function allows the user to create a custom sequence of segments that switches
+ * between modes (such as alphanumeric and byte) to encode text in less space.
+ * This is a low-level API; the high-level API is qrcodegen_encodeText() and qrcodegen_encodeBinary().
+ */
+bool qrcodegen_encodeSegmentsAdvanced(const struct qrcodegen_Segment segs[], size_t len, enum qrcodegen_Ecc ecl,
+	int minVersion, int maxVersion, enum qrcodegen_Mask mask, bool boostEcl, uint8_t tempBuffer[], uint8_t qrcode[]);
+
+
+/* 
+ * Tests whether the given string can be encoded as a segment in numeric mode.
+ * A string is encodable iff each character is in the range 0 to 9.
+ */
+bool qrcodegen_isNumeric(const char *text);
+
+
+/* 
+ * Tests whether the given string can be encoded as a segment in alphanumeric mode.
+ * A string is encodable iff each character is in the following set: 0 to 9, A to Z
+ * (uppercase only), space, dollar, percent, asterisk, plus, hyphen, period, slash, colon.
+ */
+bool qrcodegen_isAlphanumeric(const char *text);
+
+
+/* 
+ * Returns the number of bytes (uint8_t) needed for the data buffer of a segment
+ * containing the given number of characters using the given mode. Notes:
+ * - Returns SIZE_MAX on failure, i.e. numChars > INT16_MAX or the internal
+ *   calculation of the number of needed bits exceeds INT16_MAX (i.e. 32767).
+ * - Otherwise, all valid results are in the range [0, ceil(INT16_MAX / 8)], i.e. at most 4096.
+ * - It is okay for the user to allocate more bytes for the buffer than needed.
+ * - For byte mode, numChars measures the number of bytes, not Unicode code points.
+ * - For ECI mode, numChars must be 0, and the worst-case number of bytes is returned.
+ *   An actual ECI segment can have shorter data. For non-ECI modes, the result is exact.
+ */
+size_t qrcodegen_calcSegmentBufferSize(enum qrcodegen_Mode mode, size_t numChars);
+
+
+/* 
+ * Returns a segment representing the given binary data encoded in
+ * byte mode. All input byte arrays are acceptable. Any text string
+ * can be converted to UTF-8 bytes and encoded as a byte mode segment.
+ */
+struct qrcodegen_Segment qrcodegen_makeBytes(const uint8_t data[], size_t len, uint8_t buf[]);
+
+
+/* 
+ * Returns a segment representing the given string of decimal digits encoded in numeric mode.
+ */
+struct qrcodegen_Segment qrcodegen_makeNumeric(const char *digits, uint8_t buf[]);
+
+
+/* 
+ * Returns a segment representing the given text string encoded in alphanumeric mode.
+ * The characters allowed are: 0 to 9, A to Z (uppercase only), space,
+ * dollar, percent, asterisk, plus, hyphen, period, slash, colon.
+ */
+struct qrcodegen_Segment qrcodegen_makeAlphanumeric(const char *text, uint8_t buf[]);
+
+
+/* 
+ * Returns a segment representing an Extended Channel Interpretation
+ * (ECI) designator with the given assignment value.
+ */
+struct qrcodegen_Segment qrcodegen_makeEci(long assignVal, uint8_t buf[]);
+
+
+/*---- Functions to extract raw data from QR Codes ----*/
+
+/* 
+ * Returns the side length of the given QR Code, assuming that encoding succeeded.
+ * The result is in the range [21, 177]. Note that the length of the array buffer
+ * is related to the side length - every 'uint8_t qrcode[]' must have length at least
+ * qrcodegen_BUFFER_LEN_FOR_VERSION(version), which equals ceil(size^2 / 8 + 1).
+ */
+int qrcodegen_getSize(const uint8_t qrcode[]);
+
+
+/* 
+ * Returns the color of the module (pixel) at the given coordinates, which is false
+ * for light or true for dark. The top left corner has the coordinates (x=0, y=0).
+ * If the given coordinates are out of bounds, then false (light) is returned.
+ */
+bool qrcodegen_getModule(const uint8_t qrcode[], int x, int y);
+
+
+#ifdef __cplusplus
+}
+#endif

platformio.ini

@@ -60,7 +60,7 @@ lib_deps =
   EInkDisplay=symlink://open-x4-sdk/libs/display/EInkDisplay
   SDCardManager=symlink://open-x4-sdk/libs/hardware/SDCardManager
   bblanchon/ArduinoJson @ 7.4.2
-  ricmoo/QRCode @ 0.0.1
+  QRCode=symlink://lib/QRCode
   bitbank2/PNGdec @ ^1.0.0
   bitbank2/JPEGDEC @ ^1.8.0
   links2004/WebSockets @ 2.7.3

src/activities/reader/QrDisplayActivity.cpp

@@ -32,11 +32,16 @@ void QrDisplayActivity::render(RenderLock&&) {
                  tr(STR_DISPLAY_QR), nullptr);
 
   const int startY = metrics.topPadding + metrics.headerHeight + metrics.verticalSpacing;
-  const int availableHeight = contentRect.height - startY - metrics.verticalSpacing;
+  constexpr int truncNoticeHeight = 16;
+  const int availableHeight = contentRect.height - startY - metrics.verticalSpacing - truncNoticeHeight;
 
   const Rect qrBounds(contentRect.x + metrics.contentSidePadding, startY,
                       contentRect.width - metrics.contentSidePadding * 2, availableHeight);
-  QrUtils::drawQrCode(renderer, qrBounds, textPayload);
+  const bool truncated = QrUtils::drawQrCode(renderer, qrBounds, textPayload);
+
+  if (truncated) {
+    renderer.drawCenteredText(SMALL_FONT_ID, startY + availableHeight + 2, "...", true);
+  }
 
   const auto labels = mappedInput.mapLabels(tr(STR_BACK), "", "", "");
   GUI.drawButtonHints(renderer, labels.btn1, labels.btn2, labels.btn3, labels.btn4);

src/util/QrUtils.cpp

@@ -1,66 +1,88 @@
 #include "QrUtils.h"
 
 #include <Utf8.h>
-#include <qrcode.h>
+#include <qrcodegen.h>
 
 #include <algorithm>
 #include <memory>
 
 #include "Logging.h"
 
-void QrUtils::drawQrCode(const GfxRenderer& renderer, const Rect& bounds, const std::string& textPayload) {
+namespace {
-  // Dynamically calculate the QR code version based on text length
-  // Version 4 holds ~114 bytes, Version 10 ~395, Version 20 ~1066, up to 40
-  // qrcode.h max version is 40.
-  // Formula: approx version = size / 26 + 1 (very rough estimate, better to find best fit)
-  size_t len = textPayload.length();
 
-  // Truncate to max QR capacity at a UTF-8 safe boundary to avoid splitting multi-byte sequences
+bool hasNonAscii(const uint8_t* data, size_t len) {
-  static constexpr size_t MAX_QR_CAPACITY = 2953;  // Version 40, ECC_LOW, byte mode
+  for (size_t i = 0; i < len; i++) {
-  std::string truncated;
+    if (data[i] > 0x7F) return true;
-  const char* payload = textPayload.c_str();
+  }
+  return false;
+}
+
+}  // namespace
+
+bool QrUtils::drawQrCode(const GfxRenderer& renderer, const Rect& bounds, const std::string& textPayload) {
+  bool truncated = false;
+  size_t len = textPayload.size();
+  const char* text = textPayload.c_str();
+
+  // Truncate at a UTF-8 safe boundary if needed
+  std::string truncatedStr;
   if (len > MAX_QR_CAPACITY) {
-    len = utf8SafeTruncateBuffer(textPayload.c_str(), static_cast<int>(MAX_QR_CAPACITY));
+    len = utf8SafeTruncateBuffer(text, static_cast<int>(MAX_QR_CAPACITY));
-    truncated = textPayload.substr(0, len);
+    truncatedStr = textPayload.substr(0, len);
-    payload = truncated.c_str();
+    text = truncatedStr.c_str();
+    truncated = true;
+    LOG_DBG("QR", "Truncated payload from %u to %u bytes", textPayload.size(), len);
   }
 
-  int version = 4;
+  // Heap-allocate both buffers (each ~3918 bytes for version 40)
-  if (len > 114) version = 10;
+  constexpr size_t bufLen = qrcodegen_BUFFER_LEN_FOR_VERSION(qrcodegen_VERSION_MAX);
-  if (len > 395) version = 20;
+  auto qrcode = std::make_unique<uint8_t[]>(bufLen);
-  if (len > 1066) version = 30;
+  auto tempBuf = std::make_unique<uint8_t[]>(bufLen);
-  if (len > 2110) version = 40;
 
-  // Make sure we have a large enough buffer on the heap to avoid blowing the stack
+  bool ok = false;
-  uint32_t bufferSize = qrcode_getBufferSize(version);
+  const auto* rawData = reinterpret_cast<const uint8_t*>(text);
-  auto qrcodeBytes = std::make_unique<uint8_t[]>(bufferSize);
 
-  QRCode qrcode;
+  if (hasNonAscii(rawData, len)) {
-  // Initialize the QR code. We use ECC_LOW for max capacity.
+    // Non-ASCII content: use ECI mode 26 (UTF-8) + byte segment via the low-level API
-  int8_t res = qrcode_initText(&qrcode, qrcodeBytes.get(), version, ECC_LOW, payload);
+    // so scanners know the encoding rather than assuming ISO 8859-1.
+    uint8_t eciBuf[4] = {};
+    struct qrcodegen_Segment eciSeg = qrcodegen_makeEci(26, eciBuf);
 
-  if (res == 0) {
+    // Build byte segment — the segment data buffer can overlap with tempBuf
-    // Determine the optimal pixel size.
+    const size_t segBufSize = qrcodegen_calcSegmentBufferSize(qrcodegen_Mode_BYTE, len);
+    auto segBuf = std::make_unique<uint8_t[]>(segBufSize);
+    struct qrcodegen_Segment byteSeg = qrcodegen_makeBytes(rawData, len, segBuf.get());
+
+    struct qrcodegen_Segment segs[2] = {eciSeg, byteSeg};
+    ok = qrcodegen_encodeSegmentsAdvanced(segs, 2, qrcodegen_Ecc_LOW, qrcodegen_VERSION_MIN, qrcodegen_VERSION_MAX,
+                                          qrcodegen_Mask_AUTO, false, tempBuf.get(), qrcode.get());
+  } else {
+    // ASCII-only: let the library auto-select the optimal mode (numeric/alphanumeric/byte)
+    ok = qrcodegen_encodeText(text, tempBuf.get(), qrcode.get(), qrcodegen_Ecc_LOW, qrcodegen_VERSION_MIN,
+                              qrcodegen_VERSION_MAX, qrcodegen_Mask_AUTO, false);
+  }
+
+  if (ok) {
+    const int size = qrcodegen_getSize(qrcode.get());
     const int maxDim = std::min(bounds.width, bounds.height);
 
-    int px = maxDim / qrcode.size;
+    int px = maxDim / size;
     if (px < 1) px = 1;
 
-    // Calculate centering X and Y
+    const int qrDisplaySize = size * px;
-    const int qrDisplaySize = qrcode.size * px;
     const int xOff = bounds.x + (bounds.width - qrDisplaySize) / 2;
     const int yOff = bounds.y + (bounds.height - qrDisplaySize) / 2;
 
-    // Draw the QR Code
+    for (int cy = 0; cy < size; cy++) {
-    for (uint8_t cy = 0; cy < qrcode.size; cy++) {
+      for (int cx = 0; cx < size; cx++) {
-      for (uint8_t cx = 0; cx < qrcode.size; cx++) {
+        if (qrcodegen_getModule(qrcode.get(), cx, cy)) {
-        if (qrcode_getModule(&qrcode, cx, cy)) {
           renderer.fillRect(xOff + px * cx, yOff + px * cy, px, px, true);
         }
       }
     }
   } else {
-    // If it fails (e.g. text too large), log an error
+    LOG_ERR("QR", "Failed to encode QR code (%u bytes)", len);
-    LOG_ERR("QR", "Text too large for QR Code version %d", version);
   }
+
+  return truncated;
 }

src/util/QrUtils.h

@@ -8,7 +8,11 @@
 
 namespace QrUtils {
 
+// Maximum QR capacity in bytes (Version 40, ECC_LOW, byte mode).
+static constexpr size_t MAX_QR_CAPACITY = 2953;
+
 // Renders a QR code with the given text payload within the specified bounding box.
-void drawQrCode(const GfxRenderer& renderer, const Rect& bounds, const std::string& textPayload);
+// Returns true if the payload was truncated to fit the QR capacity.
+bool drawQrCode(const GfxRenderer& renderer, const Rect& bounds, const std::string& textPayload);
 
 }  // namespace QrUtils