diceware: capitalise words and embed numeral options added

Author: agrahn

app/src/main/java/app/passwordstore/ui/dialogs/DicewarePasswordGeneratorDialogFragment.kt

@@ -11,13 +11,16 @@ import android.content.Context
 import android.content.SharedPreferences
 import android.graphics.Typeface
 import android.os.Bundle
+import android.widget.CheckBox
+import androidx.annotation.IdRes
 import androidx.core.content.edit
 import androidx.fragment.app.DialogFragment
 import androidx.fragment.app.setFragmentResult
 import androidx.lifecycle.lifecycleScope
 import app.passwordstore.R
 import app.passwordstore.databinding.FragmentPwgenDicewareBinding
 import app.passwordstore.passgen.diceware.DicewarePassphraseGenerator
+import app.passwordstore.passgen.diceware.PasswordOption
 import app.passwordstore.ui.crypto.PasswordCreationActivity
 import app.passwordstore.util.crypto.AESEncryption
 import app.passwordstore.util.crypto.AESEncryption.KeyType
@@ -30,6 +33,7 @@ import javax.inject.Inject
 import kotlinx.coroutines.flow.merge
 import kotlinx.coroutines.launch
 import reactivecircus.flowbinding.android.widget.afterTextChanges
+import reactivecircus.flowbinding.android.widget.checkedChanges
 
 @AndroidEntryPoint
 class DicewarePasswordGeneratorDialogFragment : DialogFragment() {
@@ -60,8 +64,13 @@ class DicewarePasswordGeneratorDialogFragment : DialogFragment() {
     )
     binding.passwordText.typeface = Typeface.MONOSPACE
 
+    binding.includeNumeral.isChecked = prefs.getBoolean(PasswordOption.Numeral.key, false)
+    binding.capitalise.isChecked = prefs.getBoolean(PasswordOption.Capitalise.key, false)
+
     lifecycleScope.launch {
       merge(
+          binding.includeNumeral.checkedChanges().skipInitialValue(),
+          binding.capitalise.checkedChanges().skipInitialValue(),
           binding.passwordLengthText.afterTextChanges(),
           binding.passwordSeparatorText.afterTextChanges(),
         )
@@ -93,11 +102,24 @@ class DicewarePasswordGeneratorDialogFragment : DialogFragment() {
   private fun generatePassword(binding: FragmentPwgenDicewareBinding) {
     val length = binding.passwordLengthText.text?.toString()?.toIntOrNull() ?: 5
     val separator = binding.passwordSeparatorText.text?.toString()?.getOrNull(0) ?: '-'
-    setPreferences(length, separator)
-    binding.passwordText.text = dicewareGenerator.generatePassphrase(length, separator)
+    val includeNumeral = binding.includeNumeral.isChecked
+    val capitalise = binding.capitalise.isChecked
+
+    setPreferences(length, separator, includeNumeral, capitalise)
+    binding.passwordText.text =
+      dicewareGenerator.generatePassphrase(length, separator, includeNumeral, capitalise)
+  }
+
+  private fun isChecked(@IdRes id: Int): Boolean {
+    return requireDialog().findViewById<CheckBox>(id).isChecked
   }
 
-  private fun setPreferences(length: Int, separator: Char) {
+  private fun setPreferences(
+    length: Int,
+    separator: Char,
+    includeNumeral: Boolean,
+    capitalise: Boolean,
+  ) {
     prefs.edit {
       putString(
         DICEWARE_LENGTH,
@@ -111,6 +133,8 @@ class DicewarePasswordGeneratorDialogFragment : DialogFragment() {
           String(it)
         },
       )
+      putBoolean(PasswordOption.Numeral.key, includeNumeral)
+      putBoolean(PasswordOption.Capitalise.key, capitalise)
     }
   }
 }

app/src/main/res/layout/fragment_pwgen_diceware.xml

@@ -70,4 +70,21 @@
       android:maxLength="1" />
   </com.google.android.material.textfield.TextInputLayout>
 
+  <com.google.android.material.checkbox.MaterialCheckBox
+    android:id="@+id/capitalise"
+    android:layout_width="wrap_content"
+    android:layout_height="wrap_content"
+    android:layout_marginTop="8dp"
+    android:text="@string/pwgen_capitalise"
+    app:layout_constraintStart_toStartOf="parent"
+    app:layout_constraintTop_toBottomOf="@id/password_separator" />
+
+  <com.google.android.material.checkbox.MaterialCheckBox
+    android:id="@+id/include_numeral"
+    android:layout_width="wrap_content"
+    android:layout_height="wrap_content"
+    android:text="@string/pwgen_include_numeral"
+    app:layout_constraintStart_toStartOf="parent"
+    app:layout_constraintTop_toBottomOf="@id/capitalise" />
+
 </androidx.constraintlayout.widget.ConstraintLayout>

app/src/main/res/values-de/strings.xml

@@ -170,6 +170,8 @@
   <string name="pwgen_length_too_short_error">Länge zu kurz für die gewählten Kriterien.</string>
   <string name="pwgen_max_iterations_exceeded">Fehler beim Erstellen eines Passworts, das den Anforderungen genügt. Versuchen Sie es mit einem längeren Passwort.</string>
   <string name="pwgen_separator">Trennzeichen</string>
+  <string name="pwgen_capitalise">Großschreibung</string>
+  <string name="pwgen_include_numeral">Ziffer einbetten</string>
 
   <!-- Password generator prefs -->
   <string name="pref_password_generator_type_title">Passwortgenerator</string>

app/src/main/res/values/strings.xml

@@ -171,6 +171,8 @@
   <string name="pwgen_length_too_short_error">Length too short for selected criteria</string>
   <string name="pwgen_max_iterations_exceeded">Failed to generate a password satisfying the constraints. Try to increase the length.</string>
   <string name="pwgen_separator">Separator</string>
+  <string name="pwgen_capitalise">Capitalise</string>
+  <string name="pwgen_include_numeral">Include numeral</string>
 
   <!-- Password generator prefs -->
   <string name="pref_password_generator_type_title">Password generator type</string>

passgen/diceware/src/main/kotlin/app/passwordstore/passgen/diceware/DicewarePassphraseGenerator.kt

@@ -6,6 +6,8 @@
 package app.passwordstore.passgen.diceware
 
 import java.io.InputStream
+import java.security.SecureRandom
+import java.util.Locale
 import javax.inject.Inject
 
 /**
@@ -17,12 +19,28 @@ public class DicewarePassphraseGenerator
 constructor(private val die: Die, wordList: InputStream) {
 
   private val wordMap = WordListParser.parse(wordList)
+  private val random = SecureRandom()
 
   /** Generates a passphrase with [wordCount] words. */
-  public fun generatePassphrase(wordCount: Int, separator: Char): String {
+  public fun generatePassphrase(
+    wordCount: Int,
+    separator: Char,
+    includeNumeral: Boolean,
+    capitalise: Boolean,
+  ): String {
     return buildString {
+      val numeralPos = random.nextInt(wordCount)
       repeat(wordCount) { idx ->
-        append(wordMap[die.rollMultiple(DIGITS)])
+        append(
+          wordMap[die.rollMultiple(DIGITS)]?.let {
+            if (capitalise)
+              it.replaceFirstChar {
+                if (it.isLowerCase()) it.titlecase(Locale.getDefault()) else it.toString()
+              }
+            else it
+          } ?: throw NullPointerException()
+        )
+        if (idx == numeralPos && includeNumeral) append("${random.nextInt(10)}")
         if (idx < wordCount - 1) append(separator)
       }
     }

passgen/diceware/src/main/kotlin/app/passwordstore/passgen/diceware/PasswordOption.kt

@@ -0,0 +1,11 @@
+/*
+ * Copyright © 2014-2026 The Android Password Store Authors. All Rights Reserved.
+ * SPDX-License-Identifier: GPL-3.0-only
+ */
+
+package app.passwordstore.passgen.diceware
+
+public enum class PasswordOption(public val key: String) {
+  Numeral("N"),
+  Capitalise("C"),
+}

passgen/diceware/src/test/kotlin/app/passwordstore/passgen/diceware/DicewarePassphraseGeneratorTest.kt

@@ -21,6 +21,9 @@ class DicewarePassphraseGeneratorTest {
 
     val generator = DicewarePassphraseGenerator(die, WordListParserTest.getDefaultWordList())
 
-    assertEquals("salvation_cozily_croon_trustee_fidgety", generator.generatePassphrase(5, '_'))
+    assertEquals(
+      "Salvation_Cozily_Croon_Trustee_Fidgety",
+      generator.generatePassphrase(5, '_', false, true),
+    )
   }
 }