feat(receive): add adaptive receive flow and document opening

androidApp/src/main/AndroidManifest.xml

@@ -14,14 +14,21 @@
 		android:roundIcon="@mipmap/ic_launcher_round"
 		android:supportsRtl="true"
 		android:theme="@android:style/Theme.Material.NoActionBar">
+		<meta-data android:name="com.google.mlkit.vision.DEPENDENCIES" android:value="barcode_ui"/>
 		<activity
 			android:exported="true"
+			android:launchMode="singleTask"
 			android:name=".MainActivity">
 			<intent-filter>
 				<action android:name="android.intent.action.MAIN"/>
 
 				<category android:name="android.intent.category.LAUNCHER"/>
 			</intent-filter>
+			<intent-filter>
+				<action android:name="android.intent.action.VIEW"/>
+				<category android:name="android.intent.category.DEFAULT"/>
+				<data android:mimeType="application/vnd.vnidrop.transfer"/>
+			</intent-filter>
 		</activity>
 		<provider
 			android:name="androidx.core.content.FileProvider"

androidApp/src/main/kotlin/com/vnidrop/app/MainActivity.kt

@@ -1,16 +1,67 @@
 package com.vnidrop.app
 
+import android.content.Intent
+import android.net.Uri
 import android.os.Bundle
 import androidx.activity.ComponentActivity
 import androidx.activity.compose.setContent
 import androidx.activity.enableEdgeToEdge
+import androidx.lifecycle.lifecycleScope
+import com.vnidrop.app.feature.receive.ExternalInvitationController
+import com.vnidrop.app.feature.receive.MaxVniDropInvitationBytes
+import com.vnidrop.app.feature.receive.VniDropInvitationExtension
+import com.vnidrop.app.feature.receive.VniDropInvitationMimeType
+import java.nio.ByteBuffer
+import java.nio.charset.CodingErrorAction
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.withContext
 
 class MainActivity : ComponentActivity() {
+	private val externalInvitations = ExternalInvitationController()
+
 	override fun onCreate(savedInstanceState: Bundle?) {
 		enableEdgeToEdge()
 		super.onCreate(savedInstanceState)
 		setContent {
-			App(rememberAndroidAppDependencies(this))
+			App(rememberAndroidAppDependencies(this, externalInvitations))
+		}
+		handleInvitationIntent(intent)
+	}
+
+	override fun onNewIntent(intent: Intent) {
+		super.onNewIntent(intent)
+		setIntent(intent)
+		handleInvitationIntent(intent)
+	}
+
+	private fun handleInvitationIntent(source: Intent?) {
+		if (source?.action != Intent.ACTION_VIEW) return
+		val uri = source.data
+		setIntent(Intent(this, MainActivity::class.java).setAction(Intent.ACTION_MAIN))
+		if (uri == null) {
+			externalInvitations.reportOpenFailure("The invitation could not be opened")
+			return
+		}
+		lifecycleScope.launch {
+			val result = withContext(Dispatchers.IO) { readInvitation(uri, source.type) }
+			result.fold(externalInvitations::openInvitation) { error ->
+				externalInvitations.reportOpenFailure(error.message ?: "The invitation could not be opened")
+			}
 		}
 	}
+
+	private fun readInvitation(uri: Uri, declaredType: String?): Result<String> = runCatching {
+		val resolvedType = declaredType ?: contentResolver.getType(uri)
+		val hasExpectedName = uri.lastPathSegment?.endsWith(".$VniDropInvitationExtension", ignoreCase = true) == true
+		require(resolvedType == VniDropInvitationMimeType || hasExpectedName) { "This is not a VniDrop invitation" }
+		val bytes = contentResolver.openInputStream(uri)?.use { it.readNBytes(MaxVniDropInvitationBytes + 1) }
+			?: error("The invitation could not be opened")
+		require(bytes.size <= MaxVniDropInvitationBytes) { "The invitation is too large" }
+		Charsets.UTF_8.newDecoder()
+			.onMalformedInput(CodingErrorAction.REPORT)
+			.onUnmappableCharacter(CodingErrorAction.REPORT)
+			.decode(ByteBuffer.wrap(bytes))
+			.toString()
+	}
 }