Add audio transcription with per-chat language support

CMakeLists.txt

@@ -269,6 +269,8 @@ add_executable(nchat
   src/uilistborderview.h
   src/uilistdialog.cpp
   src/uilistdialog.h
+  src/uilanguagelistdialog.cpp
+  src/uilanguagelistdialog.h
   src/uilistview.cpp
   src/uilistview.h
   src/uimessagedialog.cpp
@@ -419,6 +421,9 @@ install(FILES src/nchat.1 DESTINATION "${CMAKE_INSTALL_MANDIR}/man1")
 configure_file(src/compose ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_INSTALL_LIBEXECDIR}/nchat/compose COPYONLY)
 install(PROGRAMS ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_INSTALL_LIBEXECDIR}/nchat/compose DESTINATION ${CMAKE_INSTALL_LIBEXECDIR}/nchat)
 
+configure_file(src/transcribe ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_INSTALL_LIBEXECDIR}/nchat/transcribe COPYONLY)
+install(PROGRAMS ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_INSTALL_LIBEXECDIR}/nchat/transcribe DESTINATION ${CMAKE_INSTALL_LIBEXECDIR}/nchat)
+
 # Uninstall
 if(HAS_SHARED_LIBS)
   add_custom_target(uninstall

doc/TRANSCRIPTION-SETUP.md

@@ -0,0 +1,254 @@
+# Transcription Setup
+
+How to set up different transcription backends for nchat.
+
+## What You Need
+
+- nchat installed
+- FFmpeg (`ffmpeg --version`)
+
+---
+
+## Option 1: whisper.cpp (Recommended)
+
+No Python required. Free, private, offline. `whisper.cpp` is available as a system package on most distributions.
+
+**Install whisper.cpp:**
+
+- **Arch:** `sudo pacman -S whisper.cpp` or AUR: `yay -S whisper.cpp`
+- **Debian/Ubuntu (sid):** `sudo apt install whisper.cpp`
+- **Fedora:** `sudo dnf install whisper-cpp`
+- **macOS:** `brew install whisper-cpp`
+
+**Download a model** (e.g., `base` for speed, `large-v3` for accuracy):
+
+```bash
+mkdir -p ~/.local/share/whisper
+wget https://huggingface.co/ggerganov/whisper.cpp/resolve/main/ggml-base.bin \
+  -O ~/.local/share/whisper/ggml-base.bin
+```
+
+(On macOS, use `curl -L` instead of `wget`.)
+
+**Create a transcribe script:**
+
+Create `~/.config/nchat/transcribe.sh`:
+
+```bash
+#!/usr/bin/env bash
+ffmpeg -loglevel quiet -i "$1" -f wav - \
+  | whisper-cli -m ~/.local/share/whisper/ggml-base.bin -l auto -otxt -f -
+```
+
+Make it executable:
+
+```bash
+chmod +x ~/.config/nchat/transcribe.sh
+```
+
+**Configure nchat** (`~/.config/nchat/ui.conf`):
+
+```conf
+audio_transcribe_enabled=1
+audio_transcribe_command=~/.config/nchat/transcribe.sh '%1'
+audio_transcribe_cache=1
+```
+
+**Test:**
+
+```bash
+~/.config/nchat/transcribe.sh /path/to/test.ogg
+```
+
+> **Tip:** The `audio_transcribe_command` is not special — any script that reads an audio file
+> path as its first argument and prints the transcription to stdout will work. Write your own!
+
+---
+
+## Option 2: Local Python Whisper (faster-whisper)
+
+Free, private, simple. Uses Python. Slower than whisper.cpp, uses more RAM.
+
+**Setup:**
+
+1. Install ffmpeg and Python 3.13 (or earlier; 3.14+ not yet supported):
+   ```bash
+   brew install ffmpeg python@3.13          # macOS
+   sudo apt install ffmpeg python3.13       # Debian/Ubuntu
+   sudo dnf install ffmpeg python3.13       # Fedora
+   ```
+
+2. Create a virtual environment with `uv` (recommended; `python -m venv` also works):
+   ```bash
+   mkdir -p ~/.config/nchat
+   cd ~/.config/nchat
+   uv venv --python 3.13
+   uv pip install faster-whisper
+   ```
+
+   > **Note:** Most Linux distributions no longer allow system-wide `pip install`.
+   > Use `uv` (install via `curl -LsSf https://astral.sh/uv/install.sh | sh`)
+   > or `python -m venv` instead.
+
+3. Configure nchat:
+   ```conf
+   audio_transcribe_enabled=1
+   audio_transcribe_command=~/.config/nchat/.venv/bin/python /usr/local/libexec/nchat/transcribe -f '%1' -s whisper-local -m base
+   audio_transcribe_cache=1
+   ```
+
+4. Test:
+   ```bash
+   /usr/local/libexec/nchat/transcribe -f /path/to/test.ogg -s whisper-local
+   ```
+
+Models download automatically on first use. Pick a size: `tiny` (fast, meh), `base` (balanced), `small`/`medium`/`large` (slower, better).
+
+Got an NVIDIA GPU? Install CUDA first, then:
+```bash
+uv pip install faster-whisper[gpu]
+```
+
+---
+
+## Option 3: Groq API (Faster than OpenAI, Cheaper)
+
+Cloud-based, free tier available. Fast ($0.001/min vs OpenAI's $0.006/min).
+
+**Setup:**
+
+1. Get API key from https://console.groq.com/
+
+2. Install with uv or system pip:
+   ```bash
+   uv pip install groq requests
+   ```
+
+3. Set the key:
+   ```bash
+   export GROQ_API_KEY='gsk-...'
+   echo 'export GROQ_API_KEY="gsk-..."' >> ~/.bashrc
+   echo 'export GROQ_API_KEY="gsk-..."' >> ~/.zshenv  # macOS
+   ```
+
+4. You'll need to hack the transcribe script to add Groq support (it's not built-in yet). Or use OpenAI.
+
+---
+
+## Option 4: OpenAI API
+
+Cloud-based, easiest. Fast (2-3 sec), accurate. Costs $0.006/min. Audio goes to OpenAI.
+
+**Setup:**
+
+1. Get API key: https://platform.openai.com/api-keys
+
+2. Install packages:
+   ```bash
+   uv pip install openai requests
+   ```
+
+3. Set the key:
+   ```bash
+   export OPENAI_API_KEY='sk-...'
+   echo 'export OPENAI_API_KEY="sk-..."' >> ~/.bashrc
+   ```
+
+   macOS users also need:
+   ```bash
+   echo 'export OPENAI_API_KEY="sk-..."' >> ~/.zshenv
+   ```
+
+4. Configure nchat (`~/.config/nchat/ui.conf`):
+   ```conf
+   audio_transcribe_enabled=1
+   audio_transcribe_cache=1
+   ```
+
+5. Test:
+   ```bash
+   /usr/local/libexec/nchat/transcribe -f /path/to/test.ogg
+   ```
+
+Monitor costs at https://platform.openai.com/usage (set a budget limit!)
+
+---
+
+## Testing
+
+After setup:
+
+```bash
+# Test your transcription command
+~/.config/nchat/transcribe.sh /path/to/test.ogg
+
+# Or for API-based:
+/usr/local/libexec/nchat/transcribe -f /path/to/test.ogg
+
+# Check nchat config
+grep transcribe ~/.config/nchat/ui.conf
+```
+
+In nchat: Select a voice message, press `Alt-u`, see if it works.
+
+---
+
+## Troubleshooting
+
+**"Command not found"**
+```bash
+ls -l /usr/local/libexec/nchat/transcribe  # Check if it exists
+ls -l ~/.config/nchat/transcribe.sh        # Check if script exists
+```
+
+**"No module named 'openai'" or other Python imports**
+```bash
+# If using uv:
+uv pip install openai  # or whatever package is missing
+
+# If using venv:
+~/.config/nchat/.venv/bin/pip install openai
+```
+
+**"API key not set"**
+```bash
+echo $OPENAI_API_KEY  # Check it's set
+echo $GROQ_API_KEY    # Check it's set
+echo 'export OPENAI_API_KEY="sk-..."' >> ~/.bashrc
+echo 'export OPENAI_API_KEY="sk-..."' >> ~/.zshenv  # macOS
+```
+
+**whisper-cli not found**
+```bash
+which whisper-cli  # Check if installed
+# If missing, install via your package manager (pacman, apt, dnf, brew)
+```
+
+**Timeouts**
+```conf
+audio_transcribe_timeout=60  # Increase in ui.conf
+```
+
+**Need ffmpeg**
+```bash
+brew install ffmpeg  # macOS
+sudo apt install ffmpeg  # Debian/Ubuntu
+sudo dnf install ffmpeg  # Fedora
+```
+
+**High CPU/RAM**
+
+Use a smaller model (`-m tiny`), or switch to whisper.cpp, or just use the API.
+
+---
+
+## Quick Comparison
+
+| Option | Speed | Privacy | Cost | Setup | Needs Python |
+|--------|-------|---------|------|-------|--------------|
+| whisper.cpp | Good | High | Free | Easy | No |
+| Whisper Python | OK | High | Free | Easy | Yes |
+| Groq | Fast | Low | $0.001/min | Medium | Yes |
+| OpenAI | Fast | Low | $0.006/min | Easy | Yes |
+
+Pick what works for you.