initial version

README.md

@@ -1,2 +1,90 @@
 # flipperzero-qrcode
-Display qrcodes on the Flipper Zero
+Display qrcodes on the [Flipper Zero]
+
+## Building
+First, clone the [flipperzero-firmware] repo and then clone this repo in the
+`applications_user` directory:
+
+```bash
+git clone [email protected]:flipperdevices/flipperzero-firmware.git
+cd flipperzero-firmware/applications_user
+git clone [email protected]:bmatcuk/flipperzero-qrcode.git
+```
+
+Next, in the base of the [flipperzero-firmware] directory, run fbt:
+
+```bash
+cd ..
+./fbt fap_qrcode
+```
+
+This will automatically install dependencies and build the application. When it
+has finished building, the .fap will be in
+`build/f7-firmware-D/.extapps/qrcode.fap` (fbt output will tell you where to
+find the .fap, should it change in the future).
+
+## Installation
+Copy the `qrcode.fap` file onto your [Flipper Zero] sd card in the `apps/Tools`
+directory. Then create a top level directory called `qrcodes` to store your
+qrcode files.
+
+## Creating QR Codes
+qrcode files are simple text files with the extension .qrcode. This app will
+expect them to live in a top-level directory on your sd card called `qrcodes`.
+They should have the following content:
+
+```
+Filetype: QRCode
+Version: 0
+Message: your content here
+```
+
+### Message Format
+qrcodes support 4 formats called "modes": numeric, alpha-numeric, binary, and
+kanji. Because of the limited screen real-estate on the [Flipper Zero], you'll
+want to pick the best mode for the data you are trying to display.
+
+The app will automatically detect the best mode to use, so the only thing you
+need to do is make sure the message in your file is formatted to use the best
+mode. For example, if your message is entirely numeric, make sure you don't
+include any extraneous punctuation in your file. If you're only encoding a
+domain name, make sure it's uppercase to take advantage of alpha-numeric mode,
+etc.
+
+#### Numeric Mode
+Consists of only numbers, nothing else. This mode can encode the most data.
+
+#### Alpha-Numeric Mode
+This mode can encode numbers, uppercase letters *only*, spaces, and the
+following symbols: `$%*+-./:`. This format _may_ be appropriate for urls, as
+long as you're only encoding the domain name and you remember to use uppercase
+letters (ex: `HTTP://EXAMPLE.COM`). If your url includes some path after the
+domain, you'll likely need to use binary mode because the paths are usually
+case-sensitive.
+
+A qrcode in alpha-numeric mode can encode ~40% less data than numeric mode.
+
+#### Binary Mode
+This mode is a little bit of a misnomer: binary mode simply means that the
+message will be encoded as 8-bit bytes. The qrcode standard stipulates that
+text will use ISO-8859-1 (also known as Latin-1) encoding, _not_ utf8 as would
+be the standard these days. However, _some_ readers _may_ automatically detect
+utf8. To be standard-compliant, that basically means you can only use Latin
+letters, numbers, and symbols.
+
+A qrcode in binary mode can encode ~60% less data than numeric mode, and ~30%
+less than alpha-numeric.
+
+#### Kanji Mode
+This mode is unsupported, so I won't go into detail.
+
+## qrcode library
+This application uses the [QRCode] library by ricmoo. This is the same library
+that is in the lib directory of the flipper-firmware repo (which was originally
+included for a [now-removed demo app]), but modified slightly to fix some
+compiler errors.
+
+[now-removed demo app]: https://github.com/flipperdevices/flipperzero-firmware/pull/160/files
+[flipperzero-firmware]: https://github.com/flipperdevices/flipperzero-firmware
+[Flipper Zero]: https://flipperzero.one/
+[QRCode]: https://github.com/ricmoo/QRCode

application.fam

@@ -0,0 +1,18 @@
+App(
+    appid="qrcode",
+    name="qrcode",
+    fap_description="Display qrcodes",
+    fap_author="Bob Matcuk",
+    fap_weburl="https://github.com/bmatcuk/flipperzero-qrcode",
+    apptype=FlipperAppType.EXTERNAL,
+    entry_point="qrcode_app",
+    stack_size=1024,
+    cdefines=["APP_QRCODE"],
+    requires=[
+        "gui",
+        "dialogs",
+    ],
+    fap_category="Tools",
+    fap_icon="icons/qrcode_10px.png",
+    fap_icon_assets="icons",
+)