zcash-android-wallet/app/src/main/java/cash/z/ecc/android/ui/send/SendViewModel.kt

package cash.z.ecc.android.ui.send

import androidx.lifecycle.ViewModel
import cash.z.ecc.android.lockbox.LockBox
import cash.z.ecc.android.ui.setup.WalletSetupViewModel
import cash.z.wallet.sdk.Initializer
import cash.z.wallet.sdk.Synchronizer
import cash.z.wallet.sdk.entity.PendingTransaction
import cash.z.wallet.sdk.ext.ZcashSdk
import cash.z.wallet.sdk.ext.twig
import kotlinx.coroutines.flow.Flow
import kotlinx.coroutines.flow.flow
import kotlinx.coroutines.flow.onEach
import javax.inject.Inject

class SendViewModel @Inject constructor() : ViewModel() {

    @Inject
    lateinit var lockBox: LockBox

    @Inject
    lateinit var synchronizer: Synchronizer

    @Inject
    lateinit var initializer: Initializer

    fun send(): Flow<PendingTransaction> {
        val keys = initializer.deriveSpendingKeys(
            lockBox.getBytes(WalletSetupViewModel.LockBoxKey.SEED)!!
        )
        return synchronizer.sendToAddress(
            keys[0],
            zatoshiAmount,
            toAddress,
            memo
        ).onEach {
            twig(it.toString())
        }
    }

    fun validate() = flow<String?> {

        when {
            synchronizer.validateAddress(toAddress).isNotValid -> {
                emit("Please enter a valid address")
            }
            zatoshiAmount < ZcashSdk.MINERS_FEE_ZATOSHI -> {
                emit("Please enter a larger amount")
            }
            else -> emit(null)
        }
    }

    var toAddress: String = ""
    var memo: String = ""
    var zatoshiAmount: Long = -1L
}