
Info
----

Please note that this is WIP/experimental.

The app can either send direct messages between the radios, or broadcast
messages (received by all radios).

It's basically meant to be used in an emergency situation, where internet is
not available, in order to communicate with short text messages. This kind of
mesh network is limited to about 70 nodes/radios/users to remain reliable.



Technical notes
---------------

You'll probably need to rebuild the lqml library, this app requires the latest
version.

The app uses both **BLE** (bluetooth low energy) and the **protobufs**
serialization library version 3.

For BLE you need to build the plugin in `cpp/` first (written in Qt5).

The cl-protobufs library is included here because the official version doesn't
work without the C++ plugin installed (which we don't need here). So I made
some small adaptions and included all generated proto Lisp files in order to be
independent.

Unfortunately the generated and C compiled meshtastic proto files load very
slowly on mobile. To improve load time, meshtastic proto files are simply
loaded as `*.lisp` source files, which doesn't seem to impact performance at
runtime (in this use case).

An animation is shown while loading the app, together with a counter (for older
and slow mobile devices). For this to work, the app is loaded in the background
(that is, in a separate thread).

You will see a json output of all data sent/received. It simply uses the
`print-json` convenience function from cl-protobufs.

The message db uses **sqlite**, but in a lispy manner, storing basically just a
plist for every message.

The reason I chose Qt qsqlite over cl-sqlite is mobile: Qt comes with its own
version, which is pulled in automatically, so one doesn't need to care about
OS limitations or indirect requirements.



Tested
------

Tested on Linux, macOS, Windows 10+, android, iOS.

The macOS version must be compiled first, moved to `/Applications/` and started
from Finder (not the console), otherwise BLE permissions will not work (if run
from console, the app will show a BLE exception and consume 100% CPU).

TODO: SailfishOS, using the Qt5.15 port (that is, SailfishOS using Qt5.6, with
additional Qt5.15 installed).



How to use cl-meshtastic
------------------------

Your radio needs to be turned on and bluetooth needs to be enabled before you
start the app.

On android coarse location permission is required for BLE to work.

Except for Windows, pairing of your LoRa radios is generally not needed
beforehand, the app will ask for pairing/PIN during BLE ini. If your device
doesn't have a display, use `123456` as your PIN.

On Windows it didn't work for me if not paired previously.

It may occur that your radio device is sometimes not found; some suggestions:

* try to unpair your radio from current device
* try to turn bluetooth off and on again
* try to reboot your radio

A generic bluetooth app like **nRF Connect** may help in order to see if the
devices themselves work and are able to connect.

See also [readme-usage](readme-usage.md).


Build
-----

Please apply [hacks](hacks/) before trying to build.

On **iOS** see also note in [upload-download.lisp](lisp/upload-download.lisp)
regarding function `read-sequence`, which needs to be replaced in the Quicklisp
**zip** library.


Run
---
```
lqml run.lisp
```
Optionally pass `-slime` to start a Swank server, and connect from Emacs with
`M-x slime-connect`.

During development you can pass `-auto`, which will reload all QML files after
you made a change to any of them and saved it. For re-initialization after
reloading, file `lisp/qml-reload/on-reloaded` will be loaded.

Closing the window quits the app. If you try to kill it with `ctrl-c`, you need
an additional `ctrl-d` to exit from ECL. To quit from Slime, do `(qq)` which is
short for `(qquit)`.

