This directory contains the header files (.h) defining the interfaces, data structures, and configuration constants of the ESP32 T-Display TOTP firmware. It also hosts the web_pages/ subfolder, containing minified HTML, CSS, JavaScript, and helper assets served by the local web server.

The codebase is designed as a modular, manager-based architecture. Different components communicate through unified headers and static or singleton manager classes.

graph TD
    A[main.cpp] --> B[board_config.h]
    B --> C[boards/board_esp32.h]
    B --> D[boards/board_s3.h]
    A --> E[config.h]
    A --> F[web_server.h]
    F --> G[secure_layer_manager.h]
    G --> H[crypto_manager.h]
    A --> I[display_manager.h]
    A --> J[key_manager.h]
    A --> K[PasswordManager.h]

Below is a detailed breakdown of all files located within the include/ directory.

• config.h Defines the main hardware and firmware configuration, pinouts, intervals, memory constraints, and directory paths for encrypted databases.
• board_config.h Dynamic selector file that automatically includes either boards/board_esp32.h or boards/board_s3.h depending on the PlatformIO build target.
• boards/board_esp32.h Hardware definitions for the LilyGo T-Display Classic (ESP32). Specifying pinouts for SPI, button pins, and battery monitoring channels.
• boards/board_s3.h Hardware definitions for the LilyGo T-Display-S3 (ESP32-S3). Includes parallel display configurations, native USB-OTG pinouts, and custom sleep wakeup structures.
• app_modes.h Defines the system-wide execution modes (AppMode) including TOTP Authenticator, Password Manager, AP mode, WiFi mode, and Offline mode.

• crypto_manager.h The cryptographic core of the device. Handles AES-256 (CBC/GCM) encryption/decryption, PBKDF2 key derivation, random number generation (CTR_DRBG), and supports dual-slot volumes (ActiveSpace::SPACE_A / ActiveSpace::SPACE_B) for hidden spaces.
• secure_layer_manager.h Secures browser-to-server communication using Elliptic Curve Diffie-Hellman (ECDH) key exchanges and symmetric transport encryption.
• device_static_key.h Retrieves unique hardware identifiers (e.g. chip MAC address, flash ID) to derive device-bound static encryption keys.
• pin_manager.h & PinManager.h Controls first-boot setup, startup PIN entry, duress PIN wipe triggers, lockout thresholds, and BLE pairing PIN prompts.
• secure_utils.h Low-level memory safety utilities, such as secure_memset, to prevent compilers from optimization-based dead-store elimination at -O3.

• web_server.h Declares the asynchronous web server engine, routes, session authentication tokens, and websocket handler classes.
• web_server_secure_integration.h Glues the web server route dispatchers to the SecureLayer encrypted payload wrapper handlers.
• web_admin_manager.h Admin API handler for firmware updates (OTA), data backups, space recovery, and factory resets.
• wifi_manager.h Handles WiFi client connections, SSID scanning, credentials fallback, mDNS announcements, and automatic sleep timers for saving battery.
• method_tunneling_manager.h Implements HTTP method tunneling to obscure API action signatures (e.g., encapsulating POST/DELETE requests inside tunnel envelopes).
• url_obfuscation_manager.h & url_obfuscation_integration.h Generates dynamically rotating, time-bound endpoint paths to mask server routing schemas against network scanning.
• traffic_obfuscation_manager.h & header_obfuscation_manager.h & header_obfuscation_integration.h Manages client-server transport signature camouflage by adding fake headers, variable packet padding, and dummy traffic to counter traffic analysis.

• key_manager.h Manages the encrypted database of TOTP/HOTP keys, custom sorting, counter synchronization, and dynamic API key validation.
• PasswordManager.h Implements secure password management. Handles entry serialization, encryption, categorization, dynamic passwords generation, and duplicates checking.

• display_manager.h Orchestrates the TFT LCD output. Draws current keys, timers, password badge indicators, charging details, status bars, and handles theme redraws.
• animation_manager.h High-performance rendering engine that controls smooth transition animations using Q16.16 fixed-point math configuration.
• battery_manager.h Reads analog battery levels (ADC), performs calibration, calculates charging status, and triggers low-battery warnings.
• rtc_manager.h Initializes and communicates with the external DS3231 I2C RTC module to maintain correct offline time, drift logs, and browser syncing.
• splash_manager.h Manages custom boot and splash screen drawings.
• embedded_splashes.h & embedded_splashes_s3.h Pre-compiled static boot splash icons/binaries.
• button_helpers.h Debounces physical buttons and maps clicks (single, double, long) considering the screen rotation.
• usb_hid_manager.h Handles USB HID keyboard profile setup for the T-Display-S3 to type credentials onto computers directly.
• ble_keyboard_manager.h Manages BLE keyboard emulation, pairing keys, client bonding, and password injection over Bluetooth.
• log_manager.h Circular logging engine supporting log levels (DEBUG, INFO, WARNING, ERROR, CRITICAL), serial mirroring, and memory buffering.

The web cabinet interface is compiled into header resources to reside in Flash memory (PROGMEM), avoiding SPIFFS/LittleFS read overhead.