# e-SUN Android App

Native Kotlin + Jetpack Compose app (API 35) that provides a light-therapy style full-screen white display based on Kelvin presets.

## First Increment Scope
- 3 editable temperature presets (default 3000K / 4500K / 6000K)
- 3 editable timer presets (default 5 / 10 / 30 min)
- Kelvin-to-RGB approximation for screen color
- Full-screen Shine mode with:
  - Keep-screen-on
  - Temporary in-app brightness override
  - Controls shown on touch and auto-hidden after 5s
  - Timer end returns to main screen
- Brightness persistence (default 50% on first launch)
- Placeholder ad section (`AD HERE`)
- Unit test coverage for Kelvin conversion output range

## BuildTool.sh
The project intentionally runs builds through `./BuildTool.sh` so local development and CI use the same build path.

### Common commands
```bash
./BuildTool.sh --setup-only
./BuildTool.sh --no-commit --apk-only
./BuildTool.sh --no-commit --with-aab
```

### Behavior
- `--setup-only`: prepares the local Android SDK/tooling and exits.
- `--apk-only`: builds the debug APK.
- `--with-aab`: also builds the release AAB.
- `--no-commit`: skips the post-build git commit step.
- Local builds increment `versionCode` and `versionName`.
- CI can provide `CI_VERSION_CODE` to force the build version code and `CI_ARTIFACT_TIMESTAMP` to control the release AAB filename.
- Artifacts are copied into `dist/`.
- Gitea Actions uses this same script instead of duplicating build logic in YAML.

## Upload Key (Release Signing)
For this first increment, release uses default debug signing unless custom signing is added.
Recommended future setup:
1. Generate upload key:
   ```bash
   keytool -genkeypair -v -keystore upload-keystore.jks -alias upload -keyalg RSA -keysize 2048 -validity 10000
   ```
2. Store credentials in local, untracked file (e.g. `keystore.properties`).
3. Reference it from `app/build.gradle.kts` signingConfigs.
4. Extend `BuildTool.sh` to validate presence before release builds.

## Logging
App logs key interactions and state updates through tags:
- `ESunMainViewModel`
- `ESunShine`

This keeps debugging actionable without excessive noise.