Merge abc9921959 into d403044f76

## Rationale 

I have 2 wifi access points with almost identical names, just one has
`_EXT` at the end of it. With the current display limit of 13 characters
before adding ellipsis, I can't tell which is which.

Before device screenshot with masked SSIDs:
<img
src="https://github.com/user-attachments/assets/3c5cbbaa-b2f6-412f-b5a8-6278963bd0f2"
width="300">


## Summary

Adjusted displayed length from 13 characters to 30 in the Wifi selection
screen - I've left some space for potential proportional font changes in
the future

After image with masked SSIDs:
<img
src="https://github.com/user-attachments/assets/c5f0712b-bbd3-4eec-9820-4693fae90c9f"
width="300">

---

### AI Usage

While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.

Did you use AI tools to help write this code? _**< NO >**_

README.md

@@ -95,6 +95,20 @@ Connect your Xteink X4 to your computer via USB-C and run the following command.
 ```sh
 pio run --target upload
 ```
+### Debugging
+
+After flashing the new features, it’s recommended to capture detailed logs from the serial port.
+
+First, make sure all required Python packages are installed:
+
+```python
+python3 -m pip install serial colorama matplotlib
+```
+after that run the script:
+```sh
+python3 scripts/debugging_monitor.py
+```
+This was tested on Debian and should work on most Linux systems. Minor adjustments may be required for Windows or macOS.
 
 ## Internals
 

USER_GUIDE.md

@@ -21,6 +21,7 @@ Welcome to the **CrossPoint** firmware. This guide outlines the hardware control
     - [System Navigation](#system-navigation)
   - [5. Chapter Selection Screen](#5-chapter-selection-screen)
   - [6. Current Limitations \& Roadmap](#6-current-limitations--roadmap)
+  - [7. Troubleshooting Issues \& Escaping Bootloop](#7-troubleshooting-issues--escaping-bootloop)
 
 
 ## 1. Hardware Overview
@@ -220,3 +221,15 @@ Accessible by pressing **Confirm** while inside a book.
 Please note that this firmware is currently in active development. The following features are **not yet supported** but are planned for future updates:
 
 * **Images:** Embedded images in e-books will not render.
+
+---
+
+## 7. Troubleshooting Issues & Escaping Bootloop
+
+If an issue or crash is encountered while using Crosspoint, feel free to raise an issue ticket and attach the serial monitor logs. The logs can be obtained by connecting the device to a computer and starting a serial monitor. Either [Serial Monitor](https://www.serialmonitor.org/) or the following command can be used:
+
+```
+pio device monitor
+```
+
+If the device is stuck in a bootloop, press and release the Reset button. Then, press and hold on to the configured Back button and the Power Button to boot to the Home Screen.

docs/webserver.md

@@ -153,7 +153,7 @@ Click **File Manager** to access file management features.
 
 1. Click the **+ Add** button in the top-right corner
 2. Select **New Folder** from the dropdown menu
-3. Enter a folder name (letters, numbers, underscores, and hyphens only)
+3. Enter a folder name (must not contain characters \" * : < > ? / \\ | and must not be . or ..)
 4. Click **Create Folder**
 
 This is useful for organizing your ebooks by genre, author, or series.

lib/GfxRenderer/GfxRenderer.cpp

@@ -415,13 +415,21 @@ void GfxRenderer::displayBuffer(const HalDisplay::RefreshMode refreshMode) const
 
 std::string GfxRenderer::truncatedText(const int fontId, const char* text, const int maxWidth,
                                        const EpdFontFamily::Style style) const {
+  if (!text || maxWidth <= 0) return "";
+
   std::string item = text;
-  int itemWidth = getTextWidth(fontId, item.c_str(), style);
-  while (itemWidth > maxWidth && item.length() > 8) {
-    item.replace(item.length() - 5, 5, "...");
-    itemWidth = getTextWidth(fontId, item.c_str(), style);
+  const char* ellipsis = "...";
+  int textWidth = getTextWidth(fontId, item.c_str(), style);
+  if (textWidth <= maxWidth) {
+    // Text fits, return as is
+    return item;
   }
-  return item;
+
+  while (!item.empty() && getTextWidth(fontId, (item + ellipsis).c_str(), style) >= maxWidth) {
+    utf8RemoveLastChar(item);
+  }
+
+  return item.empty() ? ellipsis : item + ellipsis;
 }
 
 // Note: Internal driver treats screen in command orientation; this library exposes a logical orientation

lib/Utf8/Utf8.cpp

@@ -29,3 +29,20 @@ uint32_t utf8NextCodepoint(const unsigned char** string) {
 
   return cp;
 }
+
+size_t utf8RemoveLastChar(std::string& str) {
+  if (str.empty()) return 0;
+  size_t pos = str.size() - 1;
+  while (pos > 0 && (static_cast<unsigned char>(str[pos]) & 0xC0) == 0x80) {
+    --pos;
+  }
+  str.resize(pos);
+  return pos;
+}
+
+// Truncate string by removing N UTF-8 characters from the end
+void utf8TruncateChars(std::string& str, const size_t numChars) {
+  for (size_t i = 0; i < numChars && !str.empty(); ++i) {
+    utf8RemoveLastChar(str);
+  }
+}

lib/Utf8/Utf8.h

@@ -1,7 +1,11 @@
 #pragma once
 
 #include <cstdint>
-
+#include <string>
 #define REPLACEMENT_GLYPH 0xFFFD
 
 uint32_t utf8NextCodepoint(const unsigned char** string);
+// Remove the last UTF-8 codepoint from a std::string and return the new size.
+size_t utf8RemoveLastChar(std::string& str);
+// Truncate string by removing N UTF-8 codepoints from the end.
+void utf8TruncateChars(std::string& str, size_t numChars);

scripts/debugging_monitor.py

@@ -0,0 +1,214 @@
+import sys
+import argparse
+import re
+import threading
+from datetime import datetime
+from collections import deque
+import time
+
+# Try to import potentially missing packages
+try:
+    import serial
+    from colorama import init, Fore, Style
+    import matplotlib.pyplot as plt
+    import matplotlib.animation as animation
+except ImportError as e:
+    missing_package = e.name
+    print("\n" + "!" * 50)
+    print(f" Error: The required package '{missing_package}' is not installed.")
+    print("!" * 50)
+
+    print(f"\nTo fix this, please run the following command in your terminal:\n")
+
+    install_cmd = "pip install "
+    packages = []
+    if 'serial' in str(e): packages.append("pyserial")
+    if 'colorama' in str(e): packages.append("colorama")
+    if 'matplotlib' in str(e): packages.append("matplotlib")
+
+    print(f"    {install_cmd}{' '.join(packages)}")
+
+    print("\nExiting...")
+    sys.exit(1)
+
+# --- Global Variables for Data Sharing ---
+# Store last 50 data points
+MAX_POINTS = 50
+time_data = deque(maxlen=MAX_POINTS)
+free_mem_data = deque(maxlen=MAX_POINTS)
+total_mem_data = deque(maxlen=MAX_POINTS)
+data_lock = threading.Lock() # Prevent reading while writing
+
+# Initialize colors
+init(autoreset=True)
+
+def get_color_for_line(line):
+    """
+    Classify log lines by type and assign appropriate colors.
+    """
+    line_upper = line.upper()
+
+    if any(keyword in line_upper for keyword in ["ERROR", "[ERR]", "[SCT]", "FAILED", "WARNING"]):
+        return Fore.RED
+    if "[MEM]" in line_upper or "FREE:" in line_upper:
+        return Fore.CYAN
+    if any(keyword in line_upper for keyword in ["[GFX]", "[ERS]", "DISPLAY", "RAM WRITE", "RAM COMPLETE", "REFRESH", "POWERING ON", "FRAME BUFFER", "LUT"]):
+        return Fore.MAGENTA
+    if any(keyword in line_upper for keyword in ["[EBP]", "[BMC]", "[ZIP]", "[PARSER]", "[EHP]", "LOADING EPUB", "CACHE", "DECOMPRESSED", "PARSING"]):
+        return Fore.GREEN
+    if "[ACT]" in line_upper or "ENTERING ACTIVITY" in line_upper or "EXITING ACTIVITY" in line_upper:
+        return Fore.YELLOW
+    if any(keyword in line_upper for keyword in ["RENDERED PAGE", "[LOOP]", "DURATION", "WAIT COMPLETE"]):
+        return Fore.BLUE
+    if any(keyword in line_upper for keyword in ["[CPS]", "SETTINGS", "[CLEAR_CACHE]"]):
+        return Fore.LIGHTYELLOW_EX
+    if any(keyword in line_upper for keyword in ["ESP-ROM", "BUILD:", "RST:", "BOOT:", "SPIWP:", "MODE:", "LOAD:", "ENTRY", "[SD]", "STARTING CROSSPOINT", "VERSION"]):
+        return Fore.LIGHTBLACK_EX
+    if "[RBS]" in line_upper:
+        return Fore.LIGHTCYAN_EX
+    if "[KRS]" in line_upper:
+        return Fore.LIGHTMAGENTA_EX
+    if any(keyword in line_upper for keyword in ["EINKDISPLAY:", "STATIC FRAME", "INITIALIZING", "SPI INITIALIZED", "GPIO PINS", "RESETTING", "SSD1677", "E-INK"]):
+        return Fore.LIGHTMAGENTA_EX
+    if any(keyword in line_upper for keyword in ["[FNS]", "FOOTNOTE"]):
+        return Fore.LIGHTGREEN_EX
+    if any(keyword in line_upper for keyword in ["[CHAP]", "[OPDS]", "[COF]"]):
+        return Fore.LIGHTYELLOW_EX
+
+    return Fore.WHITE
+
+def parse_memory_line(line):
+    """
+    Extracts Free and Total bytes from the specific log line.
+    Format: [MEM] Free: 196344 bytes, Total: 226412 bytes, Min Free: 112620 bytes
+    """
+    # Regex to find 'Free: <digits>' and 'Total: <digits>'
+    match = re.search(r"Free:\s*(\d+).*Total:\s*(\d+)", line)
+    if match:
+        try:
+            free_bytes = int(match.group(1))
+            total_bytes = int(match.group(2))
+            return free_bytes, total_bytes
+        except ValueError:
+            return None, None
+    return None, None
+
+def serial_worker(port, baud):
+    """
+    Runs in a background thread. Handles reading serial, printing to console,
+    and updating the data lists.
+    """
+    print(f"{Fore.CYAN}--- Opening {port} at {baud} baud ---{Style.RESET_ALL}")
+
+    try:
+        ser = serial.Serial(port, baud, timeout=0.1)
+        ser.dtr = False
+        ser.rts = False
+    except serial.SerialException as e:
+        print(f"{Fore.RED}Error opening port: {e}{Style.RESET_ALL}")
+        return
+
+    try:
+        while True:
+            try:
+                raw_data = ser.readline().decode('utf-8', errors='replace')
+
+                if not raw_data:
+                    continue
+
+                clean_line = raw_data.strip()
+                if not clean_line:
+                    continue
+
+                # Add PC timestamp
+                pc_time = datetime.now().strftime("%H:%M:%S")
+                formatted_line = re.sub(r"^\[\d+\]", f"[{pc_time}]", clean_line)
+
+                # Check for Memory Line
+                if "[MEM]" in formatted_line:
+                    free_val, total_val = parse_memory_line(formatted_line)
+                    if free_val is not None:
+                        with data_lock:
+                            time_data.append(pc_time)
+                            free_mem_data.append(free_val / 1024) # Convert to KB
+                            total_mem_data.append(total_val / 1024) # Convert to KB
+
+                # Print to console
+                line_color = get_color_for_line(formatted_line)
+                print(f"{line_color}{formatted_line}")
+
+            except OSError:
+                print(f"{Fore.RED}Device disconnected.{Style.RESET_ALL}")
+                break
+    except Exception as e:
+        # If thread is killed violently (e.g. main exit), silence errors
+        pass
+    finally:
+        if 'ser' in locals() and ser.is_open:
+            ser.close()
+
+def update_graph(frame):
+    """
+    Called by Matplotlib animation to redraw the chart.
+    """
+    with data_lock:
+        if not time_data:
+            return
+
+        # Convert deques to lists for plotting
+        x = list(time_data)
+        y_free = list(free_mem_data)
+        y_total = list(total_mem_data)
+
+    plt.cla() # Clear axis
+
+    # Plot Total RAM
+    plt.plot(x, y_total, label='Total RAM (KB)', color='red', linestyle='--')
+
+    # Plot Free RAM
+    plt.plot(x, y_free, label='Free RAM (KB)', color='green', marker='o')
+
+    # Fill area under Free RAM
+    plt.fill_between(x, y_free, color='green', alpha=0.1)
+
+    plt.title("ESP32 Memory Monitor")
+    plt.ylabel("Memory (KB)")
+    plt.xlabel("Time")
+    plt.legend(loc='upper left')
+    plt.grid(True, linestyle=':', alpha=0.6)
+
+    # Rotate date labels
+    plt.xticks(rotation=45, ha='right')
+    plt.tight_layout()
+
+def main():
+    parser = argparse.ArgumentParser(description="ESP32 Monitor with Graph")
+    parser.add_argument("port", nargs="?", default="/dev/ttyACM0", help="Serial port")
+    parser.add_argument("--baud", type=int, default=115200, help="Baud rate")
+    args = parser.parse_args()
+
+    # 1. Start the Serial Reader in a separate thread
+    # Daemon=True means this thread dies when the main program closes
+    t = threading.Thread(target=serial_worker, args=(args.port, args.baud), daemon=True)
+    t.start()
+
+    # 2. Set up the Graph (Main Thread)
+    try:
+        plt.style.use('light_background')
+    except:
+        pass
+
+    fig = plt.figure(figsize=(10, 6))
+
+    # Update graph every 1000ms
+    ani = animation.FuncAnimation(fig, update_graph, interval=1000)
+
+    try:
+        print(f"{Fore.YELLOW}Starting Graph Window... (Close window to exit){Style.RESET_ALL}")
+        plt.show()
+    except KeyboardInterrupt:
+        print(f"\n{Fore.YELLOW}Exiting...{Style.RESET_ALL}")
+        plt.close('all') # Force close any lingering plot windows
+
+if __name__ == "__main__":
+    main()

src/CrossPointState.cpp

@@ -5,7 +5,7 @@
 #include <Serialization.h>
 
 namespace {
-constexpr uint8_t STATE_FILE_VERSION = 2;
+constexpr uint8_t STATE_FILE_VERSION = 3;
 constexpr char STATE_FILE[] = "/.crosspoint/state.bin";
 }  // namespace
 
@@ -20,6 +20,7 @@ bool CrossPointState::saveToFile() const {
   serialization::writePod(outputFile, STATE_FILE_VERSION);
   serialization::writeString(outputFile, openEpubPath);
   serialization::writePod(outputFile, lastSleepImage);
+  serialization::writePod(outputFile, readerActivityLoadCount);
   outputFile.close();
   return true;
 }
@@ -45,6 +46,10 @@ bool CrossPointState::loadFromFile() {
     lastSleepImage = 0;
   }
 
+  if (version >= 3) {
+    serialization::readPod(inputFile, readerActivityLoadCount);
+  }
+
   inputFile.close();
   return true;
 }

src/CrossPointState.h

@@ -9,6 +9,7 @@ class CrossPointState {
  public:
   std::string openEpubPath;
   uint8_t lastSleepImage;
+  uint8_t readerActivityLoadCount = 0;
   ~CrossPointState() = default;
 
   // Get singleton instance

src/activities/home/HomeActivity.cpp

@@ -4,6 +4,7 @@
 #include <Epub.h>
 #include <GfxRenderer.h>
 #include <SDCardManager.h>
+#include <Utf8.h>
 #include <Xtc.h>
 
 #include <cstring>
@@ -366,7 +367,7 @@ void HomeActivity::render() {
         while (!lines.back().empty() && renderer.getTextWidth(UI_12_FONT_ID, lines.back().c_str()) > maxLineWidth) {
           // Remove "..." first, then remove one UTF-8 char, then add "..." back
           lines.back().resize(lines.back().size() - 3);  // Remove "..."
-          StringUtils::utf8RemoveLastChar(lines.back());
+          utf8RemoveLastChar(lines.back());
           lines.back().append("...");
         }
         break;
@@ -375,7 +376,7 @@ void HomeActivity::render() {
       int wordWidth = renderer.getTextWidth(UI_12_FONT_ID, i.c_str());
       while (wordWidth > maxLineWidth && !i.empty()) {
         // Word itself is too long, trim it (UTF-8 safe)
-        StringUtils::utf8RemoveLastChar(i);
+        utf8RemoveLastChar(i);
         // Check if we have room for ellipsis
         std::string withEllipsis = i + "...";
         wordWidth = renderer.getTextWidth(UI_12_FONT_ID, withEllipsis.c_str());
@@ -428,7 +429,7 @@ void HomeActivity::render() {
       if (!lastBookAuthor.empty()) {
         std::string trimmedAuthor = lastBookAuthor;
         while (renderer.getTextWidth(UI_10_FONT_ID, trimmedAuthor.c_str()) > maxLineWidth && !trimmedAuthor.empty()) {
-          StringUtils::utf8RemoveLastChar(trimmedAuthor);
+          utf8RemoveLastChar(trimmedAuthor);
         }
         if (renderer.getTextWidth(UI_10_FONT_ID, trimmedAuthor.c_str()) <
             renderer.getTextWidth(UI_10_FONT_ID, lastBookAuthor.c_str())) {
@@ -462,14 +463,14 @@ void HomeActivity::render() {
       // Trim author if too long (UTF-8 safe)
       bool wasTrimmed = false;
       while (renderer.getTextWidth(UI_10_FONT_ID, trimmedAuthor.c_str()) > maxLineWidth && !trimmedAuthor.empty()) {
-        StringUtils::utf8RemoveLastChar(trimmedAuthor);
+        utf8RemoveLastChar(trimmedAuthor);
         wasTrimmed = true;
       }
       if (wasTrimmed && !trimmedAuthor.empty()) {
         // Make room for ellipsis
         while (renderer.getTextWidth(UI_10_FONT_ID, (trimmedAuthor + "...").c_str()) > maxLineWidth &&
                !trimmedAuthor.empty()) {
-          StringUtils::utf8RemoveLastChar(trimmedAuthor);
+          utf8RemoveLastChar(trimmedAuthor);
         }
         trimmedAuthor.append("...");
       }

src/activities/network/WifiSelectionActivity.cpp

@@ -546,8 +546,8 @@ void WifiSelectionActivity::renderNetworkList() const {
 
       // Draw network name (truncate if too long)
       std::string displayName = network.ssid;
-      if (displayName.length() > 16) {
-        displayName.replace(13, displayName.length() - 13, "...");
+      if (displayName.length() > 33) {
+        displayName.replace(30, displayName.length() - 30, "...");
       }
       renderer.drawText(UI_10_FONT_ID, 20, networkY, displayName.c_str());
 

src/activities/reader/EpubReaderActivity.cpp

@@ -112,6 +112,8 @@ void EpubReaderActivity::onExit() {
   }
   vSemaphoreDelete(renderingMutex);
   renderingMutex = nullptr;
+  APP_STATE.readerActivityLoadCount = 0;
+  APP_STATE.saveToFile();
   section.reset();
   epub.reset();
 }
@@ -570,8 +572,8 @@ void EpubReaderActivity::renderStatusBar(const int orientedMarginRight, const in
         availableTitleSpace = rendererableScreenWidth - titleMarginLeft - titleMarginRight;
         titleMarginLeftAdjusted = titleMarginLeft;
       }
-      while (titleWidth > availableTitleSpace && title.length() > 11) {
-        title.replace(title.length() - 8, 8, "...");
+      if (titleWidth > availableTitleSpace) {
+        title = renderer.truncatedText(SMALL_FONT_ID, title.c_str(), availableTitleSpace);
         titleWidth = renderer.getTextWidth(SMALL_FONT_ID, title.c_str());
       }
     }

src/activities/reader/TxtReaderActivity.cpp

@@ -89,6 +89,8 @@ void TxtReaderActivity::onExit() {
   renderingMutex = nullptr;
   pageOffsets.clear();
   currentPageLines.clear();
+  APP_STATE.readerActivityLoadCount = 0;
+  APP_STATE.saveToFile();
   txt.reset();
 }
 
@@ -533,8 +535,8 @@ void TxtReaderActivity::renderStatusBar(const int orientedMarginRight, const int
 
     std::string title = txt->getTitle();
     int titleWidth = renderer.getTextWidth(SMALL_FONT_ID, title.c_str());
-    while (titleWidth > availableTextWidth && title.length() > 11) {
-      title.replace(title.length() - 8, 8, "...");
+    if (titleWidth > availableTextWidth) {
+      title = renderer.truncatedText(SMALL_FONT_ID, title.c_str(), availableTextWidth);
       titleWidth = renderer.getTextWidth(SMALL_FONT_ID, title.c_str());
     }
 

src/activities/reader/XtcReaderActivity.cpp

@@ -69,6 +69,8 @@ void XtcReaderActivity::onExit() {
   }
   vSemaphoreDelete(renderingMutex);
   renderingMutex = nullptr;
+  APP_STATE.readerActivityLoadCount = 0;
+  APP_STATE.saveToFile();
   xtc.reset();
 }
 

src/main.cpp

@@ -323,13 +323,15 @@ void setup() {
   APP_STATE.loadFromFile();
   RECENT_BOOKS.loadFromFile();
 
-  if (APP_STATE.openEpubPath.empty()) {
+  // Boot to home screen directly when back button is held or when reader activity crashes 3 times
+  if (APP_STATE.openEpubPath.empty() || mappedInputManager.isPressed(MappedInputManager::Button::Back) ||
+      APP_STATE.readerActivityLoadCount > 0) {
     onGoHome();
   } else {
     // Clear app state to avoid getting into a boot loop if the epub doesn't load
     const auto path = APP_STATE.openEpubPath;
     APP_STATE.openEpubPath = "";
-    APP_STATE.lastSleepImage = 0;
+    APP_STATE.readerActivityLoadCount++;
     APP_STATE.saveToFile();
     onGoToReader(path, MyLibraryActivity::Tab::Recent);
   }

src/network/html/FilesPage.html

@@ -1146,10 +1146,10 @@ function retryAllFailedUploads() {
       return;
     }
 
-    // Validate folder name (no special characters except underscore and hyphen)
-    const validName = /^[a-zA-Z0-9_\-]+$/.test(folderName);
+    // Validate folder name
+    const validName = /^(?!\.{1,2}$)[^"*:<>?\/\\|]+$/.test(folderName);
     if (!validName) {
-      alert('Folder name can only contain letters, numbers, underscores, and hyphens.');
+      alert('Folder name cannot contain \" * : < > ? / \\ | and must not be . or ..');
       return;
     }
 

src/util/StringUtils.cpp

@@ -61,23 +61,4 @@ bool checkFileExtension(const String& fileName, const char* extension) {
   return localFile.endsWith(localExtension);
 }
 
-size_t utf8RemoveLastChar(std::string& str) {
-  if (str.empty()) return 0;
-  size_t pos = str.size() - 1;
-  // Walk back to find the start of the last UTF-8 character
-  // UTF-8 continuation bytes start with 10xxxxxx (0x80-0xBF)
-  while (pos > 0 && (static_cast<unsigned char>(str[pos]) & 0xC0) == 0x80) {
-    --pos;
-  }
-  str.resize(pos);
-  return pos;
-}
-
-// Truncate string by removing N UTF-8 characters from the end
-void utf8TruncateChars(std::string& str, const size_t numChars) {
-  for (size_t i = 0; i < numChars && !str.empty(); ++i) {
-    utf8RemoveLastChar(str);
-  }
-}
-
 }  // namespace StringUtils

src/util/StringUtils.h

@@ -19,10 +19,4 @@ std::string sanitizeFilename(const std::string& name, size_t maxLength = 100);
 bool checkFileExtension(const std::string& fileName, const char* extension);
 bool checkFileExtension(const String& fileName, const char* extension);
 
-// UTF-8 safe string truncation - removes one character from the end
-// Returns the new size after removing one UTF-8 character
-size_t utf8RemoveLastChar(std::string& str);
-
-// Truncate string by removing N UTF-8 characters from the end
-void utf8TruncateChars(std::string& str, size_t numChars);
 }  // namespace StringUtils