Revert "refactor: use a ViewModel to pass around decryption passphrase"

This fails to correctly handle retries. Will re-land after I can figure out why.

This reverts commit 2fbad7ef6b42cc30c5eac79d5d166bba7cba42a4.

app/src/main/java/app/passwordstore/ui/autofill/AutofillDecryptActivity.kt

@@ -11,7 +11,6 @@ import android.content.IntentSender
 import android.os.Build
 import android.os.Bundle
 import android.view.autofill.AutofillManager
-import androidx.activity.viewModels
 import androidx.annotation.RequiresApi
 import androidx.appcompat.app.AppCompatActivity
 import androidx.lifecycle.lifecycleScope
@@ -22,7 +21,6 @@ import app.passwordstore.util.autofill.AutofillPreferences
 import app.passwordstore.util.autofill.AutofillResponseBuilder
 import app.passwordstore.util.autofill.DirectoryStructure
 import app.passwordstore.util.extensions.asLog
-import app.passwordstore.util.viewmodel.PasswordViewModel
 import com.github.androidpasswordstore.autofillparser.AutofillAction
 import com.github.androidpasswordstore.autofillparser.Credentials
 import com.github.michaelbull.result.getOrElse
@@ -79,7 +77,6 @@ class AutofillDecryptActivity : AppCompatActivity() {
     }
   }
 
-  private val viewModel: PasswordViewModel by viewModels()
   @Inject lateinit var passwordEntryFactory: PasswordEntry.Factory
   @Inject lateinit var repository: CryptoRepository
 
@@ -108,8 +105,10 @@ class AutofillDecryptActivity : AppCompatActivity() {
     val dialog = PasswordDialog()
     lifecycleScope.launch {
       withContext(Dispatchers.Main) {
-        viewModel.password.collectLatest { value ->
-          decrypt(File(filePath), clientState, action, value)
+        dialog.password.collectLatest { value ->
+          if (value != null) {
+            decrypt(File(filePath), clientState, action, value)
+          }
         }
       }
     }

app/src/main/java/app/passwordstore/ui/crypto/DecryptActivity.kt

@@ -9,7 +9,6 @@ import android.content.Intent
 import android.os.Bundle
 import android.view.Menu
 import android.view.MenuItem
-import androidx.activity.viewModels
 import androidx.lifecycle.lifecycleScope
 import app.passwordstore.R
 import app.passwordstore.data.crypto.CryptoRepository
@@ -23,7 +22,6 @@ import app.passwordstore.util.extensions.unsafeLazy
 import app.passwordstore.util.extensions.viewBinding
 import app.passwordstore.util.settings.Constants
 import app.passwordstore.util.settings.PreferenceKeys
-import app.passwordstore.util.viewmodel.PasswordViewModel
 import com.github.michaelbull.result.Err
 import com.github.michaelbull.result.Ok
 import com.github.michaelbull.result.runCatching
@@ -47,7 +45,6 @@ import logcat.logcat
 @AndroidEntryPoint
 class DecryptActivity : BasePgpActivity() {
 
-  private val viewModel: PasswordViewModel by viewModels()
   private val binding by viewBinding(DecryptLayoutBinding::inflate)
   private val relativeParentPath by unsafeLazy { getParentPath(fullPath, repoPath) }
   @Inject lateinit var passwordEntryFactory: PasswordEntry.Factory
@@ -70,7 +67,7 @@ class DecryptActivity : BasePgpActivity() {
         true
       }
     }
-    askPassphrase()
+    askPassphrase(isError = false)
   }
 
   override fun onCreateOptionsMenu(menu: Menu): Boolean {
@@ -141,36 +138,34 @@ class DecryptActivity : BasePgpActivity() {
     )
   }
 
-  private fun askPassphrase() {
+  private fun askPassphrase(isError: Boolean) {
     if (retries < MAX_RETRIES) {
       retries += 1
     } else {
       finish()
     }
-    showPasswordDialog(isError = false)
-    lifecycleScope.launch(dispatcherProvider.main()) {
-      viewModel.password.collectLatest { value ->
-        when (val result = decryptWithPassphrase(value)) {
-          is Ok -> {
-            val entry = passwordEntryFactory.create(result.value.toByteArray())
-            passwordEntry = entry
-            createPasswordUI(entry)
-            startAutoDismissTimer()
-          }
-          is Err -> {
-            logcat(ERROR) { result.error.stackTraceToString() }
-            showPasswordDialog(isError = true)
-          }
-        }
-      }
-    }
-  }
-
-  private fun showPasswordDialog(isError: Boolean) {
     val dialog = PasswordDialog()
     if (isError) {
       dialog.setError()
     }
+    lifecycleScope.launch(dispatcherProvider.main()) {
+      dialog.password.collectLatest { value ->
+        if (value != null) {
+          when (val result = decryptWithPassphrase(value)) {
+            is Ok -> {
+              val entry = passwordEntryFactory.create(result.value.toByteArray())
+              passwordEntry = entry
+              createPasswordUI(entry)
+              startAutoDismissTimer()
+            }
+            is Err -> {
+              logcat(ERROR) { result.error.stackTraceToString() }
+              askPassphrase(isError = true)
+            }
+          }
+        }
+      }
+    }
     dialog.show(supportFragmentManager, "PASSWORD_DIALOG")
   }
 

app/src/main/java/app/passwordstore/ui/crypto/PasswordDialog.kt

@@ -12,20 +12,22 @@ import android.view.KeyEvent
 import android.view.WindowManager
 import androidx.core.widget.doOnTextChanged
 import androidx.fragment.app.DialogFragment
-import androidx.fragment.app.activityViewModels
 import app.passwordstore.R
 import app.passwordstore.databinding.DialogPasswordEntryBinding
 import app.passwordstore.util.extensions.finish
 import app.passwordstore.util.extensions.unsafeLazy
-import app.passwordstore.util.viewmodel.PasswordViewModel
 import com.google.android.material.dialog.MaterialAlertDialogBuilder
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.asStateFlow
+import kotlinx.coroutines.flow.update
 
 /** [DialogFragment] to request a password from the user and forward it along. */
 class PasswordDialog : DialogFragment() {
 
-  private val viewModel: PasswordViewModel by activityViewModels()
   private val binding by unsafeLazy { DialogPasswordEntryBinding.inflate(layoutInflater) }
   private var isError: Boolean = false
+  private val _password = MutableStateFlow<String?>(null)
+  val password = _password.asStateFlow()
 
   override fun onCreateDialog(savedInstanceState: Bundle?): Dialog {
     val builder = MaterialAlertDialogBuilder(requireContext())
@@ -64,7 +66,7 @@ class PasswordDialog : DialogFragment() {
   }
 
   private fun setPasswordAndDismiss() {
-    viewModel.setPassword(binding.passwordEditText.text.toString())
+    _password.update { binding.passwordEditText.text.toString() }
     dismissAllowingStateLoss()
   }
 }

app/src/main/java/app/passwordstore/util/viewmodel/PasswordViewModel.kt

@@ -1,27 +0,0 @@
-/*
- * Copyright © 2014-2022 The Android Password Store Authors. All Rights Reserved.
- * SPDX-License-Identifier: GPL-3.0-only
- */
-
-package app.passwordstore.util.viewmodel
-
-import androidx.lifecycle.ViewModel
-import app.passwordstore.ui.crypto.PasswordDialog
-import kotlinx.coroutines.flow.MutableStateFlow
-import kotlinx.coroutines.flow.asStateFlow
-import kotlinx.coroutines.flow.dropWhile
-import kotlinx.coroutines.flow.update
-
-/**
- * ViewModel for classes that use [PasswordDialog] for getting user input. [PasswordDialog] will
- * ensure that it retrieves an instance of this [ViewModel] from the Activity scope and will post
- * values into [PasswordViewModel.password].
- */
-class PasswordViewModel : ViewModel() {
-  private val _password = MutableStateFlow("")
-  val password = _password.asStateFlow().dropWhile(String::isBlank)
-
-  fun setPassword(pass: String) {
-    _password.update { pass }
-  }
-}