Huafetcher for Android

Note: This app was converted with AI from the original python/kivy app at https://codeberg.org/vanous/huafetcher.

Huafetcher is a modern Android application written in Kotlin and Jetpack Compose for Amazfit, Xiaomi, and Huami wearable devices. It fetches device authentication keys (for companion apps such as Gadgetbridge) and downloads/packages aGPS satellite data to speed up GPS fixes on your smartwatch or fitness band.

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🌟 Key Features

• Device Auth Key Retrieval: Obtain MAC addresses and unique device auth_key values for pairing Amazfit and Xiaomi wearables with third-party tools like Gadgetbridge.
• aGPS Ephemeris & Almanac Downloader: Download satellite data packs from Huami servers:
  • cep_1week.zip & cep_7days.zip (GPS CEP)
  • lle_1week.zip (LLE / Long-term Orbit)
  • cep_pak.bin
  • epo.zip (EPO)
  • lto.zip (LTO)
• aGPS Binary Packager (aGPS_UIHH.bin): Automatically unpacks, verifies CRC32 checksums, and compiles component almanac files (gps_alm.bin, gln_alm.bin, lle_*.lle) into standard aGPS_UIHH.bin and gps_uihh.bin binaries with custom UIHH headers.
• Dual Authentication Modes:
  • Amazfit Account: Direct email and password login.
  • Xiaomi / Mi Account: Built-in WebView OAuth authorization flow.
• Flexible Data Storage:
  • Store generated files in External App Storage, Public Downloads, or Internal App Storage.
  • Custom folder name configuration.
  • One-click file cleaning and folder management.
• First-Start Wizard & Quick Setup: Guided onboarding workflow for first-time users to set up login credentials, preferred export files, and storage locations.

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🛠️ Architecture & Tech Stack

• Language: Kotlin
• UI Framework: Jetpack Compose with Material Design 3
• Architecture: MVVM (Model-View-ViewModel) with StateFlow
• Networking: OkHttp3
• Data Persistence: Android SharedPreferences (PreferencesManager)
• Binary & ZIP Processing: java.util.zip (ZipInputStream, CRC32), Little-Endian binary packaging

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🚀 Getting Started

Prerequisites

• Android Studio Ladybug or later
• JDK 17+
• Android SDK (API 26+)

Build & Installation

1. Clone the repository:

   git clone <repository-url>

2. Open the project in Android Studio.
3. Build the debug APK using Gradle:

   gradle assembleDebug

4. Install on your Android device or emulator:

   gradle installDebug

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📱 Usage

1. Initial Setup: On first run, complete the First-Start Setup Wizard to configure your login method (Amazfit or Xiaomi Account) and select storage preferences.
2. Fetch Auth Keys: On the main dashboard, tap Fetch Auth Keys to retrieve your connected wearable device's MAC address and key.
3. Fetch aGPS Data: Tap Fetch aGPS Data to download the latest satellite data packs.
4. Build aGPS_UIHH.bin: Tap Pack UIHH File to synthesize component almanac packs into a ready-to-flash aGPS_UIHH.bin.
5. Export & Share: Share or export generated files directly to Gadgetbridge or your filesystem.

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📄 License & Acknowledgments

Converted with AI from the original Python/Kivy Huafetcher project by vanous:

• Original Repository: https://codeberg.org/vanous/huafetcher