Add drafty human friendly current metrics

[NeimadTL]

Currently, the metrics are always shown with the in milliampere (e.i, using the "mA" unit). A nicer way would be to have those metrics shown in more friendly way (e.g, 1A -> 1A, 1000A -> 1kA, 0.000001A -> 1μA...etc). At this point, this is just a draft of how it would be implemented.

Related to #2944

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 15.35%. Comparing base (b2b21e1) to head (86ba1dd).

Additional details and impacted files

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##             main    #4433   +/-   ##
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  Coverage   15.35%   15.35%           
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  Files          83       83           
  Lines        4344     4344           
  Branches      734      734           
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  Hits          667      667           
  Misses       3553     3553           
  Partials      124      124           

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[NeimadTL]

@DaneEvans @jamesarich, could you please have look when you'll get some time please (couldn't assign it you for some reason). Also, I've got to do the same for the distance metric but couldn't find it in feature/node/src/main/kotlin/org/meshtastic/feature/node/metrics/EnvironmentMetrics.kt. Thank you.

[Copilot]

Pull request overview

This pull request implements human-friendly formatting for electrical current metrics in the Environment Metrics display. Instead of always showing values in milliamperes (mA), it introduces intelligent unit scaling (μA, mA, A, kA, etc.) based on the magnitude of the value. This addresses issue #2944, which requests more readable display of large metric values (e.g., showing "18.2 A" instead of "18200 mA").

Changes:

• Added numberToHuman() utility function to convert numeric values to human-readable format with appropriate SI prefixes
• Added BASE_UNITS and AMPERE_UNITS constant maps to support unit conversion
• Updated current display in EnvironmentMetrics.kt to use the new formatting function

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 8 comments.

File	Description
core/model/src/main/kotlin/org/meshtastic/core/model/util/UnitConversions.kt	Adds numberToHuman function and unit conversion constants for intelligent unit prefix selection
feature/node/src/main/kotlin/org/meshtastic/feature/node/metrics/EnvironmentMetrics.kt	Updates current value display to use numberToHuman instead of fixed mA formatting

[DaneEvans]

Go through the copilot stuff, most of it seems sensible.

Remember we want this generalised for all units / areas eventually (windspeed, distance etc.)
The mappings should be unnecessary, especially to amps in particular.
A string insertion ala (python) f"{f0.2 value}{SIprefix}{ Unit}" should be adequate.

[NeimadTL]

Thanks for your feedback @DaneEvans. Made the changes but looks like there other issue which I haven't figured out yet. Any suggestion please ?

FYI, the same warning appears the last CI run:

Configure project :core:strings
w: ⚠️ Unused Kotlin Source Sets
The Kotlin source set commonTest was configured but not added to any Kotlin compilation.
Solution: You can add a source set to a target's compilation by connecting it with the compilation's default source set using 'dependsOn'.
See https://kotl.in/connecting-source-sets

[jamesarich]

one thing you missed - you updated the EnvironmentMetrics chart to use base Amperes, but there are still several places hardcoded to display the raw telemetry values as mA.
for the app to be consistent, you need to wrap the raw values in your new convertToBaseUnit() and swap the string formatting over to A in these files:

• feature/node/src/main/kotlin/org/meshtastic/feature/node/metrics/PowerMetrics.kt (lines ~280 and ~386)
• feature/node/src/main/kotlin/org/meshtastic/feature/node/component/PowerMetrics.kt (line ~51, and the other channels)
• feature/node/src/main/kotlin/org/meshtastic/feature/node/component/EnvironmentMetrics.kt (line ~103)
• feature/node/src/main/kotlin/org/meshtastic/feature/node/component/NodeItem.kt (line ~365)

[jamesarich]

Preferred in Kotlin to write this as an extension property or function directly on the Float (or Number) type.

val Float.milliToBase: Float get() = this / 1000f

This can then be used everywhere in the code:

envMetrics.current?.milliToBase

[jamesarich]

Let's get rid of the !! here and wrap this with ?.let.

envMetrics.current?.let { currentMilli ->
    val current = convertToBaseUnit(currentMilli)
    Text(
        text = "%s %.2f A".format(stringResource(Res.string.current), current),
        // ...
    )
}

[jamesarich]

Move String formatting into Compose Resources. Rather than doing "%s %.2f A".format(stringResource(Res.string.current), current) inside the Composable, it is best practice to move the format specifier directly into the strings.xml. e.g., <string name="current_value_format">%1$s %2$.2f A</string> And then in Compose: stringResource(Res.string.current_value_format, stringResource(Res.string.current), current) This is safer for localization and keeps your UI code much cleaner.