Update README.md

README.md

@@ -1,51 +1,49 @@
+<img src="./app/src/main/ic_launcher-raw.png" alt="Logo" align="right" height="60" />
+
 # Dive Log
-This repository contains code for a dive log Android app that can read dives from
+This repository contains code for a dive log Android app that can import dives from
 [hwOS](https://heinrichsweikamp.com/hw-os) family of dive computers (e.g. Heinrichs Weikamp OSTC Sport) via Bluetooth
 LE (BLE).
 
-Feature Plan:
-- MVP:
-  - Offline-first dive log
-  - Fetch and merge dive logs from dive computer
-  - Plot of dive profile
-- Next steps:
-  - Synchronize dive logs in external cloud (e.g. Google Drive)
-  - Additional data (equipment, observations, tags)
-- Ideas:
-  - Storing images
-  - Map with dive locations
-  - CSV export / import
-  - User defined data fields (e.g. weights, tank, etc.)
-  - Buddy signature via NFC
-  - Support for more dive computers
-  - In-app payments (only if there are any running server costs)
-- Out of scope:
-  - User accounts
-  - Dive certificates
-  - Social media stuff
+
+## Features
+
+MVP:
+- Offline-first dive log
+- Fetch and merge dive logs from dive computer
+- Plot of dive profile
+- Add and edit notes
+
+Tech:
+- [Jetpack Compose](https://developer.android.com/jetpack/compose)
+- [Material 3 Dynamic Color Support](https://m3.material.io/styles/color/dynamic-color/overview) 
+- CI/CD via [GitHub Actions](https://github.com/features/actions)
+
+Next steps:
+- Map of dive spots
+- Synchronize dive logs in external cloud (e.g. Google Drive)
+- CSV export / import
+- Additional data (equipment, observations, tags, images)
+- Support for more dive computers
 
 
 ## Modules
-- `app`: The application or presentation layer. Contains compose views, viewmodels, resources, etc.
+- `app`: The UI layer. Contains compose views, viewmodels, resources, etc.
 - `data`: The data layer. Contains business logic components, e.g. `DiveRepository`.
 - `bluetooth`: Generic bluetooth connectivity, permission and pairing handling. No domain specific code.
+- `persistence`: Local SQLite database.
 
 
-## Communication Concept
-Bluetooth LE endpoints are called characteristics (e.g. "firmware revision" or "battery level") and are grouped into
-services (e.g. "device information"). Characteristics and services are identified by UUIDs. Characteristics can allow:
-- reading
-- writing (with or without response, like TCP/UDP)
-- notifications/indications (app gets notified by device if a value changed, with our without acknowledgement)
-
-hwOS does not use Bluetooth LE characteristics directly as endpoints for fetching dives. Instead communication is done
-through a **simulated virtual serial COM port** over four specific BLE characteristics. This is based on a
-"Terminal I/O v2.0" protocol by Telit Wireless Solutions (formerly Stollmann E+V GmbH).
-
-See [Terminal I/O Profile Client Implementation Guide](http://www.iot.com.tr/uploads/pdf/TIO_Implementation_Guide_r05.pdf).
+## Bluetooth Import
 
+### Bluetooth LE
+Bluetooth LE endpoints are called characteristics (e.g. "firmware revision" or "battery level"). They are grouped into
+services (e.g. "device information"). Characteristics and services are identified by UUIDs. Characteristics can allow:
+- Reading
+- Writing (with or without response, like TCP/UDP)
+- Notifications/Indications (app gets notified by device if a value changed, with our without acknowledgement)
 
-## BLE API
+A hwOS device has these endpoints:
 - Service: Generic Access (`0x1800`)
     - Characteristic: Device Name (`0x2A00`, `READ`) &rarr; "OSTCs 21876"
     - Characteristic: Appearance (`0x2A01`, `READ`)
@@ -58,8 +56,13 @@ See [Terminal I/O Profile Client Implementation Guide](http://www.iot.com.tr/upl
     - Characteristic: UART Credits RX (`00000003-0000-1000-8000-008025000000`, `WRITE`)
     - Characteristic: UART Credits TX (`00000004-0000-1000-8000-008025000000`, `INDICATE`)
 
+### Communication Workflow
+See [Terminal I/O Profile Client Implementation Guide](http://www.iot.com.tr/uploads/pdf/TIO_Implementation_Guide_r05.pdf).
+
+hwOS does not use Bluetooth LE characteristics directly as endpoints for fetching dives. Instead communication is done
+through a **simulated virtual serial COM port** over four specific BLE characteristics. This is based on the
+"Terminal I/O v2.0 protocol" by Telit Wireless Solutions (formerly Stollmann E+V GmbH).
 
-## Connection Workflow
 1. App connects to (previously bonded) BLE device
 2. App sets up indication to Credits TX
 3. App sets up notification to Data TX
@@ -69,8 +72,9 @@ See [Terminal I/O Profile Client Implementation Guide](http://www.iot.com.tr/upl
     - Send commands via Data RX
     - Receive responses via Data TX
 
+### Package Format
+See [hwOS API specification](https://code.heinrichsweikamp.com/public/hwos_code/raw-file/tip/doc/hwos_interface.pdf).
 
-## Package Format
 Requests:
 - Byte 0: Command ID
 - Byte 1...n: Payload (variable length payloads like strings are `0x00` terminated)
@@ -80,10 +84,10 @@ Responses:
 - Byte 1...(n-1): Payload
 - Byte n: `0x4D`
 
-See [hwOS API specification](https://code.heinrichsweikamp.com/public/hwos_code/raw-file/tip/doc/hwos_interface.pdf).
-
+### Download Dives
+See [OstcConnection.kt](./data/src/main/kotlin/cloud/mike/divelog/data/importer/ostc/OstcConnection.kt) for
+implementation details.
 
-## Download Dives
 First off we have to enable download mode by sending the "start communication" command (`0xBB`). Afterwards we can end
 communication by sending the "exit communication" command (`0xFF`). This will kill the bluetooth connection.
 
@@ -96,12 +100,9 @@ We have three options:
     - 65536 bytes total
     - Includes more information than compact headers, like surface pressure, min. temperature, gas mix, deco model, etc.
 - Send "get dive profile" command (`0x66`) with dive number (0-255).
-    - Sends full header and dive profile
+    - Sends full header and dive profile)
     - Profile has variable length, e.g. ~21 kB for a one-hour dive
-
-See [OstcConnection.kt](./data/src/main/kotlin/cloud/mike/divelog/data/importer/ostc/OstcConnection.kt) for
-implementation details.
-
+    - Profile contains depth and events like gas mix change
 
 ## Links
 - [Mike's Android Bluetooth Guide](https://mike.cloud/android/2021/05/19/bluetooth.html)