(feat: android) Added a sample of using Halo2 in Android, as well as …

…improved the UI to visually switch between Circom and Halo2 (#218)

test-e2e/android/app/src/main/assets/fibonacci_pk.bin

@@ -0,0 +1 @@
+../../../../../../test-vectors/halo2/fibonacci_pk.bin

test-e2e/android/app/src/main/assets/fibonacci_srs.bin

@@ -0,0 +1 @@
+../../../../../../test-vectors/halo2/fibonacci_srs.bin

test-e2e/android/app/src/main/assets/fibonacci_vk.bin

@@ -0,0 +1 @@
+../../../../../../test-vectors/halo2/fibonacci_vk.bin

test-e2e/android/app/src/main/java/com/mopro/mopro_app/FibonacciComponent.kt

@@ -0,0 +1,76 @@
+package com.mopro.mopro_app
+
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.width
+import androidx.compose.material3.Button
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.text.font.FontWeight
+import androidx.compose.ui.unit.dp
+import uniffi.mopro.GenerateProofResult
+import uniffi.mopro.generateHalo2Proof
+import uniffi.mopro.verifyHalo2Proof
+
+@Composable
+fun FibonacciComponent() {
+    var provingTime by remember { mutableStateOf("proving time:") }
+    var verifyingTime by remember { mutableStateOf("verifying time: ") }
+    var valid by remember { mutableStateOf("valid:") }
+    var res by remember {
+        mutableStateOf<GenerateProofResult>(
+            GenerateProofResult(proof = ByteArray(size = 0), inputs = ByteArray(size = 0))
+        )
+    }
+
+    val srsPath = getFilePathFromAssets("fibonacci_srs.bin")
+    val provingKeyPath = getFilePathFromAssets("fibonacci_pk.bin")
+    val verifyingKeyPath = getFilePathFromAssets("fibonacci_vk.bin")
+
+
+    val inputs = mutableMapOf<String, List<String>>()
+    inputs["out"] = listOf("55")
+
+    Box(modifier = Modifier.fillMaxSize().padding(16.dp), contentAlignment = Alignment.Center) {
+        Button(
+            onClick = {
+                Thread {
+                    val startTime = System.currentTimeMillis()
+                    res = generateHalo2Proof(srsPath, provingKeyPath, inputs)
+                    val endTime = System.currentTimeMillis()
+                    provingTime =
+                        "proving time: " +
+                                (endTime - startTime).toString() +
+                                " ms"
+                }
+                    .start()
+            },
+            modifier = Modifier.padding(top = 20.dp)
+        ) { Text(text = "generate proof") }
+        Button(
+            onClick = {
+                val startTime = System.currentTimeMillis()
+                valid = "valid: " + verifyHalo2Proof(srsPath, verifyingKeyPath, res.proof, res.inputs).toString()
+                val endTime = System.currentTimeMillis()
+                verifyingTime = "verifying time: " + (endTime - startTime).toString() + " ms"
+            },
+            modifier = Modifier.padding(top = 120.dp)
+        ) { Text(text = "verify proof") }
+        Text(
+            text = "Halo2 Fibonacci proof",
+            modifier = Modifier.padding(bottom = 180.dp),
+            fontWeight = FontWeight.Bold
+        )
+
+        Text(text = provingTime, modifier = Modifier.padding(top = 250.dp).width(200.dp))
+        Text(text = valid, modifier = Modifier.padding(top = 300.dp).width(200.dp))
+        Text(text = verifyingTime, modifier = Modifier.padding(top = 350.dp).width(200.dp))
+    }
+}

test-e2e/android/app/src/main/java/com/mopro/mopro_app/MainActivity.kt

@@ -4,61 +4,78 @@ import MultiplierComponent
 import android.os.Bundle
 import androidx.activity.ComponentActivity
 import androidx.activity.compose.setContent
-import androidx.activity.enableEdgeToEdge
 import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Spacer
 import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.height
 import androidx.compose.foundation.layout.padding
-import androidx.compose.material3.Scaffold
-import androidx.compose.material3.Text
-import androidx.compose.runtime.Composable
+import androidx.compose.material3.*
+import androidx.compose.runtime.*
 import androidx.compose.ui.Modifier
-import androidx.compose.ui.tooling.preview.Preview
+import androidx.compose.ui.platform.LocalContext
+import androidx.compose.ui.unit.dp
 import com.mopro.mopro_app.ui.theme.MoproappTheme
 import java.io.File
 import java.io.IOException
 import java.io.InputStream
 import java.io.OutputStream
 
 @Throws(IOException::class)
-private fun copyFile(`in`: InputStream, out: OutputStream) {
+fun copyFile(inputStream: InputStream, outputStream: OutputStream) {
     val buffer = ByteArray(1024)
     var read: Int
-    while ((`in`.read(buffer).also { read = it }) != -1) {
-        out.write(buffer, 0, read)
+    while (inputStream.read(buffer).also { read = it } != -1) {
+        outputStream.write(buffer, 0, read)
+    }
+}
+
+@Composable
+fun getFilePathFromAssets(name: String): String {
+    val context = LocalContext.current
+    return remember {
+        val assetManager = context.assets
+        val inputStream = assetManager.open(name)
+        val file = File(context.filesDir, name)
+        copyFile(inputStream, file.outputStream())
+        file.absolutePath
     }
 }
 
 class MainActivity : ComponentActivity() {
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
-        enableEdgeToEdge()
         setContent {
             MoproappTheme {
-                Scaffold(modifier = Modifier.fillMaxSize()) { innerPadding ->
-                    val s = assets.open("multiplier2_final.zkey")
-                    val f = File(filesDir, "multiplier2_final.zkey")
-                    copyFile(s, f.outputStream())
-                    Column(modifier = Modifier.fillMaxSize().padding(paddingValues = innerPadding)) {
-                        MultiplierComponent(f.absolutePath)
-                    }
-                }
+                MainScreen()
             }
         }
     }
 }
 
 @Composable
-fun Greeting(name: String, modifier: Modifier = Modifier) {
-    Text(
-        text = "Hello $name!",
-        modifier = modifier
-    )
-}
+fun MainScreen() {
+    var selectedTab by remember { mutableStateOf(0) }
+    val tabs = listOf("Circom", "Halo2")
 
-@Preview(showBackground = true)
-@Composable
-fun GreetingPreview() {
-    MoproappTheme {
-        Greeting("Android")
+    Scaffold(modifier = Modifier.fillMaxSize()) { innerPadding ->
+        Column(modifier = Modifier
+            .fillMaxSize()
+            .padding(innerPadding)
+        ) {
+            TabRow(selectedTabIndex = selectedTab) {
+                tabs.forEachIndexed { index, title ->
+                    Tab(
+                        text = { Text(title) },
+                        selected = selectedTab == index,
+                        onClick = { selectedTab = index }
+                    )
+                }
+            }
+            Spacer(modifier = Modifier.height(16.dp))
+            when (selectedTab) {
+                0 -> MultiplierComponent()
+                1 -> FibonacciComponent()
+            }
+        }
     }
 }

test-e2e/android/app/src/main/java/com/mopro/mopro_app/MultiplierComponent.kt

@@ -4,22 +4,18 @@ import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.layout.width
 import androidx.compose.material3.Button
 import androidx.compose.material3.Text
-import androidx.compose.runtime.Composable
-import androidx.compose.runtime.getValue
-import androidx.compose.runtime.mutableStateOf
-import androidx.compose.runtime.remember
-import androidx.compose.runtime.setValue
+import androidx.compose.runtime.*
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.unit.dp
+import com.mopro.mopro_app.getFilePathFromAssets
 import uniffi.mopro.GenerateProofResult
 import uniffi.mopro.generateCircomProof
 import uniffi.mopro.verifyCircomProof
-import java.nio.file.Paths
 
 @Composable
-fun MultiplierComponent(zkeyPath: String) {
+fun MultiplierComponent() {
     var initTime by remember { mutableStateOf("init time:") }
     var provingTime by remember { mutableStateOf("proving time:") }
     var verifyingTime by remember { mutableStateOf("verifying time: ") }
@@ -35,6 +31,8 @@ fun MultiplierComponent(zkeyPath: String) {
     inputs["a"] = listOf("3")
     inputs["b"] = listOf("5")
 
+    val zkeyPath = getFilePathFromAssets("multiplier2_final.zkey")
+
     Box(modifier = Modifier.fillMaxSize().padding(16.dp), contentAlignment = Alignment.Center) {
         Button(
             onClick = {
@@ -43,13 +41,9 @@ fun MultiplierComponent(zkeyPath: String) {
                         val startTime = System.currentTimeMillis()
                         res = generateCircomProof(zkeyPath, inputs)
                         val endTime = System.currentTimeMillis()
-                        provingTime =
-                            "proving time: " +
-                                    (endTime - startTime).toString() +
-                                    " ms"
+                        provingTime = "proving time: " + (endTime - startTime).toString() + " ms"
                     }
-                )
-                    .start()
+                ).start()
             },
             modifier = Modifier.padding(top = 20.dp)
         ) { Text(text = "generate proof") }