From b1ce8ab74952fc4ab350517937d0445faac35a52 Mon Sep 17 00:00:00 2001
From: channa-figure <73041609+channa-figure@users.noreply.github.com>
Date: Tue, 1 Jun 2021 17:01:13 -0600
Subject: [PATCH] Add domain extension to get escrow account address (#121)

---
 CHANGELOG.md                                  |  1 +
 .../explorer/grpc/extensions/Domain.kt        | 11 +++++++++-
 .../explorer/domain/ExtensionsTest.kt         | 22 ++++++++++++++-----
 3 files changed, 27 insertions(+), 7 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 6964b8a9..c0dcff0e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -36,6 +36,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 ### Features
 * IBC denom API #97
   * `/ibc/all`
+* Add get escrow account address method for ibc #119
 
 ### Improvements
 * Removed hash conversion #66
diff --git a/service/src/main/kotlin/io/provenance/explorer/grpc/extensions/Domain.kt b/service/src/main/kotlin/io/provenance/explorer/grpc/extensions/Domain.kt
index ccfb3e56..a20b4a48 100644
--- a/service/src/main/kotlin/io/provenance/explorer/grpc/extensions/Domain.kt
+++ b/service/src/main/kotlin/io/provenance/explorer/grpc/extensions/Domain.kt
@@ -1,14 +1,17 @@
 package io.provenance.explorer.grpc.extensions
 
+import com.google.common.io.BaseEncoding
 import com.google.protobuf.Any
 import com.google.protobuf.ByteString
 import cosmos.auth.v1beta1.Auth
 import cosmos.base.query.v1beta1.Pagination
 import cosmos.crypto.multisig.Keys
 import io.provenance.explorer.domain.core.logger
+import io.provenance.explorer.domain.core.toBech32Data
 import io.provenance.explorer.domain.extensions.edPubKeyToBech32
 import io.provenance.explorer.domain.extensions.secpPubKeyToBech32
 import io.provenance.explorer.domain.extensions.toBase64
+import io.provenance.explorer.domain.extensions.toSha256
 import io.provenance.explorer.service.prettyRole
 import io.provenance.marker.v1.Access
 import io.provenance.marker.v1.MarkerAccount
@@ -80,7 +83,13 @@ fun Any.toAddress(hrpPrefix: String) =
         else -> null.also { logger().error("This typeUrl is not supported as a consensus address: $typeUrl") }
     }
 
-
+//TODO: Once cosmos-sdk implements a grpc endpoint for this we can replace this with grpc Issue: https://github.com/cosmos/cosmos-sdk/issues/9437
+fun getEscrowAccountAddress(portId: String, channelId: String, hrpPrefix: String) : String {
+    val contents = "${portId}/${channelId}".toByteArray()
+    var preImage = "ics20-1".encodeToByteArray() + 0x0.toByte() + contents
+    val hash = preImage.toSha256().copyOfRange(0, 20)
+    return hash.toBech32Data(hrpPrefix).address
+}
 
 
 fun getPaginationBuilder(offset: Int, limit: Int) =
diff --git a/service/src/test/kotlin/io/provenance/explorer/domain/ExtensionsTest.kt b/service/src/test/kotlin/io/provenance/explorer/domain/ExtensionsTest.kt
index 951f631b..9d5eaabe 100644
--- a/service/src/test/kotlin/io/provenance/explorer/domain/ExtensionsTest.kt
+++ b/service/src/test/kotlin/io/provenance/explorer/domain/ExtensionsTest.kt
@@ -1,6 +1,16 @@
-//package io.provenance.explorer.domain
-//
-//class ExtensionsTest {
-//
-//
-//}
+package io.provenance.explorer.domain
+
+import io.provenance.explorer.grpc.extensions.getEscrowAccountAddress
+import org.junit.jupiter.api.Assertions.assertEquals
+import org.junit.jupiter.api.Tag
+import org.junit.jupiter.api.Test
+
+class ExtensionsTest {
+
+    @Test
+    @Tag("junit-jupiter")
+    fun `should return escrow account address with given portId channelId and prefix`() {
+        val result = getEscrowAccountAddress("transfer", "channel", "cosmos")
+        assertEquals("cosmos1dm7fargcm8km25nxe6xldj0y0j2dawg8h5s03l", result)
+    }
+}