Refactor payment code to make it easier to extend

1 files changed, 136 insertions, 0 deletions

diff --git a/app/src/main/java/net/taler/wallet/payment/PromptPaymentFragment.kt b/app/src/main/java/net/taler/wallet/payment/PromptPaymentFragment.kt
new file mode 100644
index 0000000..4b4bf01
--- /dev/null
+++ b/app/src/main/java/net/taler/wallet/payment/PromptPaymentFragment.kt
@@ -0,0 +1,136 @@
+/*
+ This file is part of GNU Taler
+ (C) 2019 Taler Systems S.A.
+
+ GNU Taler is free software; you can redistribute it and/or modify it under the
+ terms of the GNU General Public License as published by the Free Software
+ Foundation; either version 3, or (at your option) any later version.
+
+ GNU Taler is distributed in the hope that it will be useful, but WITHOUT ANY
+ WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+ A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License along with
+ GNU Taler; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
+ */
+
+package net.taler.wallet.payment
+
+import android.annotation.SuppressLint
+import android.os.Bundle
+import android.view.LayoutInflater
+import android.view.View
+import android.view.View.INVISIBLE
+import android.view.View.VISIBLE
+import android.view.ViewGroup
+import androidx.fragment.app.Fragment
+import androidx.fragment.app.activityViewModels
+import androidx.lifecycle.observe
+import androidx.navigation.fragment.findNavController
+import kotlinx.android.synthetic.main.fragment_prompt_payment.*
+import net.taler.wallet.Amount
+import net.taler.wallet.R
+import net.taler.wallet.WalletViewModel
+
+/**
+ * Show a payment and ask the user to accept/decline.
+ */
+class PromptPaymentFragment : Fragment() {
+
+    private val model: WalletViewModel by activityViewModels()
+    private val paymentManager by lazy { model.paymentManager }
+
+    override fun onCreateView(
+        inflater: LayoutInflater, container: ViewGroup?,
+        savedInstanceState: Bundle?
+    ): View? {
+        return inflater.inflate(R.layout.fragment_prompt_payment, container, false)
+    }
+
+    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
+        paymentManager.payStatus.observe(viewLifecycleOwner, this::onPaymentStatusChanged)
+
+        button_abort_payment.setOnClickListener {
+            when (val ps = paymentManager.payStatus.value) {
+                is PayStatus.Prepared -> {
+                    paymentManager.abortProposal(ps.proposalId)
+                }
+            }
+            paymentManager.resetPayStatus()
+            findNavController().navigateUp()
+        }
+    }
+
+    private fun showLoading(show: Boolean) {
+        model.showProgressBar.value = show
+    }
+
+    private fun onPaymentStatusChanged(payStatus: PayStatus) {
+        when (payStatus) {
+            is PayStatus.Prepared -> {
+                showLoading(false)
+                showOrder(payStatus.contractTerms, payStatus.totalFees)
+                button_confirm_payment.isEnabled = true
+                button_confirm_payment.setOnClickListener {
+                    showLoading(true)
+                    paymentManager.confirmPay(payStatus.proposalId)
+                    button_confirm_payment.isEnabled = false
+                }
+            }
+            is PayStatus.InsufficientBalance -> {
+                showLoading(false)
+                showOrder(payStatus.contractTerms, null)
+                error_text.setText(R.string.payment_balance_insufficient)
+                fadeInView(error_text)
+            }
+            is PayStatus.Success -> {
+                showLoading(false)
+                paymentManager.resetPayStatus()
+                findNavController().navigate(R.id.action_promptPayment_to_paymentSuccessful)
+            }
+            is PayStatus.AlreadyPaid -> {
+                showLoading(false)
+                paymentManager.resetPayStatus()
+                findNavController().navigate(R.id.action_promptPayment_to_alreadyPaid)
+            }
+            is PayStatus.Error -> {
+                showLoading(false)
+                error_text.text = getString(R.string.payment_error, payStatus.error)
+                fadeInView(error_text)
+            }
+            is PayStatus.None -> {
+                // No payment active.
+                showLoading(false)
+            }
+            is PayStatus.Loading -> {
+                // Wait until loaded ...
+                showLoading(true)
+            }
+        }
+    }
+
+    private fun showOrder(contractTerms: ContractTerms, totalFees: Amount?) {
+        order_summary.text = contractTerms.summary
+        val amount = contractTerms.amount
+        @SuppressLint("SetTextI18n")
+        order_amount.text = "${amount.amount} ${amount.currency}"
+        if (totalFees != null && !totalFees.isZero()) {
+            val fee = "${totalFees.amount} ${totalFees.currency}"
+            order_fees_amount.text = getString(R.string.payment_fee, fee)
+            fadeInView(order_fees_amount)
+        } else {
+            order_fees_amount.visibility = INVISIBLE
+        }
+        fadeInView(order_summary_label)
+        fadeInView(order_summary)
+        fadeInView(order_amount_label)
+        fadeInView(order_amount)
+    }
+
+    private fun fadeInView(v: View) {
+        v.alpha = 0f
+        v.visibility = VISIBLE
+        v.animate().alpha(1f).start()
+    }
+
+}