[#891] ZEC/TAZ currency distinction

sdk-ext-lib/src/androidTest/java/cash/z/ecc/sdk/type/ZcashCurrencyTest.kt

@@ -0,0 +1,48 @@
+package cash.z.ecc.sdk.type
+
+import androidx.test.core.app.ApplicationProvider
+import androidx.test.filters.SmallTest
+import org.junit.Assert.assertEquals
+import org.junit.Test
+import kotlin.test.assertNotSame
+
+class ZcashCurrencyTest {
+
+    @SmallTest
+    @Test
+    fun check_is_zec_type() {
+        assertEquals(
+            ZcashCurrency.ZEC,
+            ZcashCurrency.fromResources(ApplicationProvider.getApplicationContext())
+        )
+    }
+
+    @SmallTest
+    @Test
+    fun wrong_network_type() {
+        assertNotSame(
+            ZcashCurrency.TAZ.network,
+            ZcashCurrency.fromResources(ApplicationProvider.getApplicationContext()).network
+        )
+    }
+
+    @SmallTest
+    @Test
+    fun check_zec_properties() {
+        val zecType = ZcashCurrency.ZEC
+
+        assertEquals(ZcashCurrency.ZEC.id, zecType.id)
+        assertEquals(ZcashCurrency.ZEC.name, zecType.name)
+        assertEquals(ZcashCurrency.ZEC.network, zecType.network)
+    }
+
+    @SmallTest
+    @Test
+    fun check_taz_properties() {
+        val tazType = ZcashCurrency.TAZ
+
+        assertEquals(ZcashCurrency.TAZ.id, tazType.id)
+        assertEquals(ZcashCurrency.TAZ.name, tazType.name)
+        assertEquals(ZcashCurrency.TAZ.network, tazType.network)
+    }
+}

sdk-ext-lib/src/main/java/cash/z/ecc/sdk/model/ZecRequest.kt

@@ -8,12 +8,14 @@ import cash.z.ecc.sdk.fixture.Zip321UriParseFixture
 data class ZecRequest(val address: WalletAddress.Unified, val amount: Zatoshi, val message: ZecRequestMessage) {
 
     // TODO [#397]: Waiting for an implementation of Uri parser in SDK project
+    // TODO [#397]: https://github.com/zcash/zcash-android-wallet-sdk/issues/397
     suspend fun toUri(): String {
         return Zip321UriBuildFixture.new(this)
     }
 
     companion object {
         // TODO [#397]: Waiting for an implementation of Uri parser in SDK project
+        // TODO [#397]: https://github.com/zcash/zcash-android-wallet-sdk/issues/397
         suspend fun fromUri(uriString: String): ZecRequest {
             return Zip321UriParseFixture.new(uriString)
         }
@@ -28,6 +30,7 @@ value class ZecRequestMessage(val value: String) {
 
     companion object {
         // TODO [#219]: Define a maximum message length
+        // TODO [#219]: https://github.com/zcash/secant-android-wallet/issues/219
         // Also note that the length varies from what the user types in versus the encoded version
         // that is actually sent.
         const val MAX_MESSAGE_LENGTH = 320

sdk-ext-lib/src/main/java/cash/z/ecc/sdk/type/ZcashCurrency.kt

@@ -0,0 +1,35 @@
+package cash.z.ecc.sdk.type
+
+import android.content.Context
+import cash.z.ecc.android.sdk.model.ZcashNetwork
+
+/**
+ * This class provides Zcash currency types with a distinction mechanism. There is the ZEC currency type, which applies
+ * to the Mainnet network type, and TAZ, which applies to the Testnet network type. The currencies can't be mismatched
+ * and are tightly connected to their network type.
+ *
+ * To get some TAZs to your test wallet, visit Testnet faucet: https://faucet.zecpages.com/
+ */
+sealed class ZcashCurrency(
+    val id: Int = 0,
+    val name: String = "TAZ",
+    val network: ZcashNetwork = ZcashNetwork.Testnet
+) {
+    object TAZ : ZcashCurrency(id = 0, name = "TAZ", network = ZcashNetwork.Testnet)
+
+    object ZEC : ZcashCurrency(id = 1, name = "ZEC", network = ZcashNetwork.Mainnet)
+
+    override fun toString(): String = "ZcashCurrency: id=$id, name=$name, network:$network"
+
+    companion object {
+        fun fromResources(context: Context) =
+            when (ZcashNetwork.fromResources(context)) {
+                ZcashNetwork.Mainnet ->
+                    ZEC
+                ZcashNetwork.Testnet ->
+                    TAZ
+                else ->
+                    error("Not supported ZcashNetwork type while getting ZcashCurrency type.")
+            }
+    }
+}