ble_proximity_signal_platform_interface

A common platform interface for the ble_proximity_signal federated plugin.

This package defines:

• Platform contract (BleProximitySignalPlatform)
• Shared configuration models (ScanConfig, BroadcastConfig)
• Shared raw model (RawScanResult)

If you are a plugin user, you typically do not depend on this package directly. If you are implementing a new platform (or maintaining Android/iOS implementations), this is the source of truth.

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Overview

Contract shape

Platform implementations must provide:

• startBroadcast(token:, config:) / stopBroadcast()
• startScan(targetTokens:, config:) / stopScan()
• debugDiscoverServices(deviceId:, timeoutMs:) (debug helper)
• Stream<RawScanResult> get scanResults (event stream)

The ble_proximity_signal Dart wrapper consumes this stream and applies smoothing/hysteresis to produce Stream<ProximityEvent>.

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RawScanResult payload contract

Platforms must emit RawScanResult.fromMap(...) compatible maps over the event channel. Minimum required fields:

• targetToken (String)
• rssi (int)
• timestampMs (int, epoch millis)

Optional fields (best-effort, may be null):

• deviceId, deviceName, localName, localNameHex
• manufacturerDataLen, manufacturerDataHex
• serviceDataLen, serviceDataUuids, serviceDataHex
• serviceUuids

Notes

• timestampMs uses Unix epoch ms for cross-platform consistency.
• targetToken is the identifier extracted from the advertising payload. In debug modes, implementations may fall back to deviceId.
• localNameHex, serviceDataHex, and manufacturerDataHex should contain hex-encoded payloads for debugging; keep them compact and best-effort.

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Config models

BroadcastConfig

• serviceUuid (String, 128-bit UUID)
• txPower (int? hint; platform may ignore)

ScanConfig

• serviceUuid (String)
• debugAllowAll (bool)

The Dart wrapper enforces targetTokens.length <= 5 when debugAllowAll == false. Platforms may enforce as well.

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Implementing a new platform

Create a package and extend BleProximitySignalPlatform.

Key rules:

1. Register your implementation by setting BleProximitySignalPlatform.instance = ...
2. Stream raw scan events via scanResults
3. Match map keys exactly for RawScanResult.fromMap

Recommended checklist:

• Event channel emits required keys (targetToken, rssi, timestampMs)
• timestampMs uses epoch milliseconds
• startScan can accept up to 5 target tokens
• Best-effort populate optional debug fields
• stopScan and stopBroadcast are idempotent
• Debug discovery returns a human-readable dump string

Example debug discovery output:

deviceId: <id>
name: <device name>
service <uuid>
  char <uuid> props=read|notify

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