Load drone OUIs from asset

.gitignore

@@ -1,3 +1,6 @@
-# Generated binary assets
-app/
+# Generated binary assets and build outputs
+app/build/
+app/src/main/assets/
+app/src/main/res/
+
 __pycache__/

README.md

@@ -14,3 +14,13 @@ python3 scripts/bootstrap_assets.py
 
 This will recreate the `rotor_v1.tflite` model and the required PNG
 drawables under `app/src/main/...`.
+
+## Refresh drone OUI prefixes
+
+`assets/drone_ouis.json` tracks MAC address prefixes for common drone
+vendors. Regenerate it from a locally downloaded IEEE `oui.csv` file:
+
+```bash
+python3 scripts/update_drone_ouis.py /path/to/oui.csv
+python3 scripts/bootstrap_assets.py  # copy JSON into app assets
+```

app/src/main/java/com/vantagescanner/DroneSignalDetector.kt

@@ -0,0 +1,37 @@
+package com.vantagescanner
+
+import android.content.Context
+import org.json.JSONArray
+import java.io.BufferedReader
+import java.util.Locale
+
+/**
+ * Detects drone Wi-Fi signals by comparing MAC prefixes against a
+ * locally maintained list of Organizationally Unique Identifiers.
+ *
+ * OUI prefixes are loaded from the `drone_ouis.json` asset at runtime
+ * to avoid hard-coding vendor data.
+ */
+class DroneSignalDetector(private val context: Context) {
+    private val droneOuis: Set<String> by lazy { loadOuis() }
+
+    private fun loadOuis(): Set<String> {
+        context.assets.open("drone_ouis.json").use { input ->
+            val text = input.bufferedReader().use(BufferedReader::readText)
+            val arr = JSONArray(text)
+            val set = mutableSetOf<String>()
+            for (i in 0 until arr.length()) {
+                set += arr.getString(i).uppercase(Locale.US)
+            }
+            return set
+        }
+    }
+
+    /**
+     * Returns true if the MAC address belongs to a known drone vendor.
+     */
+    fun isDrone(macAddress: String): Boolean {
+        val prefix = macAddress.uppercase(Locale.US).replace(":", "").take(6)
+        return prefix in droneOuis
+    }
+}

assets/drone_ouis.json

@@ -0,0 +1,17 @@
+[
+  "00121C",
+  "00267E",
+  "04A85A",
+  "0C9AE6",
+  "34D262",
+  "381D14",
+  "481CB9",
+  "58B858",
+  "60601F",
+  "8C5823",
+  "9003B7",
+  "903AE6",
+  "9C5A8A",
+  "A0143D",
+  "E47A2C"
+]

scripts/bootstrap_assets.py

@@ -2,7 +2,8 @@
 """Decode base64-encoded assets into their binary forms.
 
 Designed for air-gapped setups: keeps repository text-only and restores
-binary assets locally. Currently handles rotor model and PNG icons.
+binary assets locally. Handles the rotor model, PNG icons, and JSON
+lookup tables.
 """
 import base64
 from pathlib import Path
@@ -29,6 +30,12 @@ def main() -> None:
     for b64_file in ASSET_SRC.glob('*.png.b64'):
         out_name = b64_file.name[:-4]  # strip .b64
         decode_file(b64_file, DRAWABLE_DST / out_name)
+    # JSON assets (copied as-is)
+    for json_file in ASSET_SRC.glob('*.json'):
+        dst = MODEL_DST / json_file.name
+        dst.parent.mkdir(parents=True, exist_ok=True)
+        dst.write_text(json_file.read_text())
+        print(f"copied {json_file} -> {dst}")
 
 
 if __name__ == '__main__':

scripts/update_drone_ouis.py

@@ -0,0 +1,57 @@
+#!/usr/bin/env python3
+"""Generate assets/drone_ouis.json from an IEEE OUI CSV.
+
+The IEEE registry file `oui.csv` can be downloaded separately and stored
+locally for offline use. This script extracts OUI prefixes for known drone
+vendors and writes them to a JSON asset.
+"""
+import argparse
+import csv
+import json
+import re
+from pathlib import Path
+from typing import List
+
+# Keywords identifying drone manufacturers in the IEEE registry
+DRONE_KEYWORDS = ["DJI", "PARROT", "SKYDIO"]
+
+ROOT = Path(__file__).resolve().parent.parent
+ASSET_PATH = ROOT / "assets" / "drone_ouis.json"
+
+
+def extract_ouis(csv_path: Path) -> List[str]:
+    ouis: set[str] = set()
+    with csv_path.open(newline="") as fh:
+        reader = csv.DictReader(fh)
+        for row in reader:
+            name = row.get("Organization Name", "").upper()
+            for key in DRONE_KEYWORDS:
+                if key in name:
+                    assignment = re.sub("[^0-9A-F]", "", row["Assignment"].upper())
+                    ouis.add(assignment)
+                    break
+    return sorted(ouis)
+
+
+def main() -> None:
+    parser = argparse.ArgumentParser(description=__doc__)
+    parser.add_argument(
+        "csv", nargs="?", default="oui.csv", help="Path to downloaded oui.csv"
+    )
+    parser.add_argument(
+        "-o",
+        "--output",
+        default=str(ASSET_PATH),
+        help="Destination JSON asset (default: assets/drone_ouis.json)",
+    )
+    args = parser.parse_args()
+    csv_path = Path(args.csv)
+    ouis = extract_ouis(csv_path)
+    out_path = Path(args.output)
+    out_path.parent.mkdir(parents=True, exist_ok=True)
+    out_path.write_text(json.dumps(ouis, indent=2) + "\n")
+    print(f"wrote {len(ouis)} OUIs -> {out_path}")
+
+
+if __name__ == "__main__":
+    main()