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+# Whisper Dictation — GUI App Design
+
+**Date:** 2026-03-20
+**Status:** Approved
+
+## Overview
+
+Convert the existing `dictate.py` script into a proper packaged desktop application that:
+- Runs without a terminal window on Windows and Linux
+- Shows a compact log/status panel accessible from the tray icon
+- Can be integrated into the system (autostart, start menu, desktop shortcut)
+- Is distributed as a standalone binary via PyInstaller
+
+## Module Structure
+
+```
+whisper-dictation/
+├── main.py                        # Entry point
+├── build.py                       # PyInstaller build script (platform-specific)
+├── whisper-dictation.spec         # PyInstaller spec (manual, for ctranslate2)
+├── whisper_app/
+│   ├── __init__.py
+│   ├── app.py                     # AppState, central coordination, log queue
+│   ├── audio.py                   # sounddevice stream, audio_callback
+│   ├── transcriber.py             # WhisperModel, stop_and_transcribe()
+│   ├── hotkey.py                  # HotkeyListener (unchanged)
+│   ├── config.py                  # load/save config + vocab, path resolution
+│   ├── typer.py                   # type_text(), cross-platform
+│   ├── tray.py                    # pystray icon + menu
+│   ├── log_window.py              # Compact log panel
+│   ├── settings_window.py         # Settings dialog
+│   ├── vocab_window.py            # Vocabulary dialog
+│   ├── overlay.py                 # "Recording..." overlay
+│   └── installer.py               # System integration (autostart, start menu, shortcut)
+├── config.json                    # Shared config (git-tracked)
+├── vocabulary.json                # Shared vocabulary (git-tracked)
+├── start.sh                       # Dev start (Linux)
+└── start.bat                      # Dev start (Windows)
+```
+
+## Path Handling
+
+All path resolution lives in `config.py`. Must work in two modes:
+
+```python
+import sys, os
+
+def _app_dir() -> str:
+    """Root dir for config.json and vocabulary.json."""
+    if getattr(sys, "frozen", False):
+        # PyInstaller binary: use directory containing the executable
+        return os.path.dirname(sys.executable)
+    else:
+        # Dev mode: use script directory (git repo root)
+        return os.path.dirname(os.path.abspath(__file__ + "/../../"))
+```
+
+Machine-local config (`config_local.json`) continues to use `%LOCALAPPDATA%\WhisperDictation` (Windows) or `~/.local/share/WhisperDictation` (Linux) — unchanged.
+
+## Logging Architecture
+
+`app.py` owns a `queue.Queue[str]` and a pre-queue buffer list.
+
+```python
+_log_buffer: list[str] = []   # before queue is ready
+_log_queue: queue.Queue | None = None
+
+def log(msg: str) -> None:
+    if _log_queue is not None:
+        _log_queue.put(msg)
+    else:
+        _log_buffer.append(msg)
+
+def set_log_queue(q: queue.Queue) -> None:
+    global _log_queue
+    _log_queue = q
+    for msg in _log_buffer:
+        q.put(msg)
+    _log_buffer.clear()
+```
+
+All `print()` calls in all modules are replaced with `app.log()`.
+
+## Log Panel (Compact)
+
+Opened via tray icon left-click or "Anzeigen" menu item. Implemented in `log_window.py`.
+
+```
+┌─────────────────────────────────────┐
+│ ● WHISPER DICTATION    medium·de  ✕ │
+├─────────────────────────────────────┤
+│ Model ready.                        │
+│ Hotkey: ctrl+shift+space            │
+│ ● Recording...                      │
+│ Audio: 2.1s  RMS: 0.048             │
+│ ✓ "Das ist ein Test"                │
+├─────────────────────────────────────┤
+│ ⚙ Einstellungen  📚 Vokabular  🗑  │
+└─────────────────────────────────────┘
+```
+
+- Size: ~380×220px, **not resizable**
+- `tk.Text` widget in read-only mode, max 200 lines (older lines discarded)
+- Auto-scroll to bottom on new messages
+- Color tags: green = ready/result, red = recording, yellow = transcribing, grey = info
+- Close button → `withdraw()` (does not quit the app)
+- 🗑 button → clears the text widget
+- Queue polled via `root.after(100, _poll_log_queue)`
+
+## Settings Window — Installation Section
+
+New section "INSTALLATION" added to the existing settings window. Implemented in `installer.py`.
+
+Each integration shows status ("eingerichtet" / "nicht eingerichtet") and two buttons: "Einrichten" / "Entfernen".
+
+| Feature | Windows | Linux |
+|---|---|---|
+| Autostart beim Login | `HKCU\Software\Microsoft\Windows\CurrentVersion\Run` | `~/.config/autostart/whisper-dictation.desktop` |
+| Startmenü-Eintrag | `%APPDATA%\Microsoft\Windows\Start Menu\Programs\Whisper Dictation.lnk` | `~/.local/share/applications/whisper-dictation.desktop` |
+| Desktop-Verknüpfung | `%USERPROFILE%\Desktop\Whisper Dictation.lnk` | `~/Desktop/whisper-dictation.desktop` |
+
+Windows `.lnk` files are created via `pywin32` (`win32com.client.Dispatch("WScript.Shell")`).
+
+**Only available when running as a frozen binary.** In dev mode, the buttons are disabled with a tooltip "Nur im gebauten Binary verfügbar".
+
+## Icon
+
+The existing tray icon (64×64 PIL `Image`) is extended:
+- At build time, `build.py` generates `icon.ico` (sizes: 16, 32, 48, 256) via Pillow
+- Used as the PyInstaller `--icon` and for `.lnk` shortcuts
+
+## PyInstaller Build
+
+### Manual `.spec` file (required for ctranslate2/faster-whisper)
+
+```python
+# whisper-dictation.spec (key sections)
+a = Analysis(
+    ['main.py'],
+    hiddenimports=[
+        'ctranslate2',
+        'faster_whisper',
+        'sounddevice',
+        'pynput.keyboard._win32',   # Windows
+        'pynput.keyboard._xorg',    # Linux
+    ],
+    datas=[
+        ('config.json', '.'),
+        ('vocabulary.json', '.'),
+    ],
+)
+exe = EXE(a.pure, ..., console=False, icon='icon.ico')
+```
+
+### `build.py`
+
+1. Generates `icon.ico` from PIL
+2. Runs PyInstaller with the `.spec` file
+3. Copies `config.json` and `vocabulary.json` into `dist/whisper-dictation/`
+
+### Platform requirement
+
+PyInstaller cannot cross-compile. **Build must be run separately on each platform:**
+- Windows: `python build.py` → `dist/whisper-dictation/whisper-dictation.exe`
+- Linux: `python build.py` → `dist/whisper-dictation/whisper-dictation`
+
+## New Dependencies
+
+| Package | Purpose |
+|---|---|
+| `pywin32` | `.lnk` shortcut creation (Windows only) |
+
+Added to `requirements-windows.txt`. Not required on Linux.
+
+## Out of Scope
+
+- Code signing / notarization
+- Auto-updater
+- Versioning
+- Cross-compilation
+
+## Open Questions
+
+_(none — all resolved during design session)_