Refactor: remove isAvailable(), make build() return Skill<*>?

app/src/main/kotlin/org/stypox/dicio/eval/SkillHandler.kt

@@ -10,7 +10,6 @@ import kotlinx.coroutines.flow.collectLatest
 import kotlinx.coroutines.flow.combine
 import kotlinx.coroutines.flow.distinctUntilChanged
 import kotlinx.coroutines.launch
-import org.dicio.skill.skill.Skill
 import org.dicio.skill.skill.SkillInfo
 import org.stypox.dicio.di.LocaleManager
 import org.stypox.dicio.di.SkillContextImpl
@@ -73,7 +72,7 @@ class SkillHandler @Inject constructor(
 
     private val _skillRanker = MutableStateFlow(
         // an initial dummy value, will be overwritten directly by the launched job
-        SkillRanker(listOf(), buildSkillFromInfo(fallbackSkillInfoList[0]))
+        SkillRanker(listOf(), fallbackSkillInfoList[0].build(skillContext)!!)
     )
     val skillRanker: StateFlow<SkillRanker> = _skillRanker
 
@@ -87,21 +86,17 @@ class SkillHandler @Inject constructor(
 
                     val newEnabledSkillsInfo = allSkillInfoList
                         .filter { enabledSkills.getOrDefault(it.id, true) }
-                        .filter { it.isAvailable(skillContext) }
+                        .mapNotNull { info -> info.build(skillContext)?.let { skill -> Pair(info, skill) } }
 
-                    _enabledSkillsInfo.value = newEnabledSkillsInfo
+                    _enabledSkillsInfo.value = newEnabledSkillsInfo.map { (info, _skill) -> info }
                     _skillRanker.value = SkillRanker(
-                        newEnabledSkillsInfo.map(::buildSkillFromInfo),
-                        buildSkillFromInfo(fallbackSkillInfoList[0]),
+                        newEnabledSkillsInfo.map { (_info, skill) -> skill },
+                        fallbackSkillInfoList[0].build(skillContext)!!,
                     )
                 }
         }
     }
 
-    private fun buildSkillFromInfo(skillInfo: SkillInfo): Skill<*> {
-        return skillInfo.build(skillContext)
-    }
-
     companion object {
         fun newForPreviews(context: Context): SkillHandler {
             return SkillHandler(

app/src/main/kotlin/org/stypox/dicio/settings/SkillSettingsScreen.kt

@@ -113,9 +113,12 @@ fun SkillSettingsScreen(
             }
         }
         items(skills) { skill ->
+            // Note: calling build() here is slightly wasteful as it constructs a skill object
+            // just to check availability, but it ensures correct results regardless of whether
+            // the skill is enabled or disabled by the user.
             SkillSettingsItem(
                 skill = skill,
-                isAvailable = skill.isAvailable(viewModel.skillContext),
+                isAvailable = skill.build(viewModel.skillContext) != null,
                 enabled = enabledSkills.getOrDefault(skill.id, true),
                 setEnabled = { enabled -> viewModel.setSkillEnabled(skill.id, enabled) }
             )

app/src/main/kotlin/org/stypox/dicio/settings/SkillSettingsViewModel.kt

@@ -7,7 +7,6 @@ import androidx.lifecycle.viewModelScope
 import dagger.hilt.android.lifecycle.HiltViewModel
 import kotlinx.coroutines.flow.map
 import kotlinx.coroutines.launch
-import org.dicio.skill.context.SkillContext
 import org.dicio.skill.skill.SkillInfo
 import org.stypox.dicio.di.SkillContextInternal
 import org.stypox.dicio.settings.datastore.UserSettings

app/src/main/kotlin/org/stypox/dicio/skills/calculator/CalculatorInfo.kt

@@ -22,13 +22,10 @@ object CalculatorInfo : SkillInfo("calculator") {
     override fun icon() =
         rememberVectorPainter(Icons.Default.Calculate)
 
-    override fun isAvailable(ctx: SkillContext): Boolean {
-        return Sentences.Calculator[ctx.sentencesLanguage] != null &&
-                Sentences.CalculatorOperators[ctx.sentencesLanguage] != null &&
-                ctx.parserFormatter != null
-    }
-
-    override fun build(ctx: SkillContext): Skill<*> {
-        return CalculatorSkill(CalculatorInfo, Sentences.Calculator[ctx.sentencesLanguage]!!)
+    override fun build(ctx: SkillContext): Skill<*>? {
+        val sentences = Sentences.Calculator[ctx.sentencesLanguage] ?: return null
+        val operators = Sentences.CalculatorOperators[ctx.sentencesLanguage] ?: return null
+        if (ctx.parserFormatter == null) return null
+        return CalculatorSkill(CalculatorInfo, sentences, operators)
     }
 }

app/src/main/kotlin/org/stypox/dicio/skills/calculator/CalculatorSkill.kt

@@ -13,8 +13,11 @@ import org.stypox.dicio.sentences.Sentences.CalculatorOperators
 import java.text.DecimalFormat
 import java.text.DecimalFormatSymbols
 
-class CalculatorSkill(correspondingSkillInfo: SkillInfo, data: StandardRecognizerData<Calculator>)
-    : StandardRecognizerSkill<Calculator>(correspondingSkillInfo, data) {
+class CalculatorSkill(
+    correspondingSkillInfo: SkillInfo,
+    data: StandardRecognizerData<Calculator>,
+    private val operatorRecognizerData: StandardRecognizerData<CalculatorOperators>,
+) : StandardRecognizerSkill<Calculator>(correspondingSkillInfo, data) {
 
     private fun getOperation(
         ctx: SkillContext,
@@ -47,7 +50,6 @@ class CalculatorSkill(correspondingSkillInfo: SkillInfo, data: StandardRecognize
             return CalculatorOutput(null, "", "")
         }
 
-        val operatorRecognizerData = CalculatorOperators[ctx.sentencesLanguage]!!
         var firstNumber: Number
         var i: Int
         if (textWithNumbers[0] is Number) {

app/src/main/kotlin/org/stypox/dicio/skills/current_time/CurrentTimeInfo.kt

@@ -22,11 +22,8 @@ object CurrentTimeInfo : SkillInfo("current_time") {
     override fun icon() =
         rememberVectorPainter(Icons.Default.Watch)
 
-    override fun isAvailable(ctx: SkillContext): Boolean {
-        return Sentences.CurrentTime[ctx.sentencesLanguage] != null
-    }
-
-    override fun build(ctx: SkillContext): Skill<*> {
-        return CurrentTimeSkill(CurrentTimeInfo, Sentences.CurrentTime[ctx.sentencesLanguage]!!)
+    override fun build(ctx: SkillContext): Skill<*>? {
+        val data = Sentences.CurrentTime[ctx.sentencesLanguage] ?: return null
+        return CurrentTimeSkill(CurrentTimeInfo, data)
     }
 }

app/src/main/kotlin/org/stypox/dicio/skills/fallback/text/TextFallbackInfo.kt

@@ -21,10 +21,6 @@ object TextFallbackInfo : SkillInfo("text") {
     override fun icon() =
         rememberVectorPainter(Icons.Default.Warning)
 
-    override fun isAvailable(ctx: SkillContext): Boolean {
-        return true
-    }
-
     override fun build(ctx: SkillContext): Skill<*> {
         return TextFallbackSkill(TextFallbackInfo)
     }

app/src/main/kotlin/org/stypox/dicio/skills/flashlight/FlashlightInfo.kt

@@ -24,13 +24,11 @@ object FlashlightInfo : SkillInfo("flashlight") {
     override fun icon() =
         rememberVectorPainter(Icons.Default.FlashlightOn)
 
-    override fun isAvailable(ctx: SkillContext): Boolean {
-        return Sentences.Flashlight[ctx.sentencesLanguage] != null &&
-                ctx.android.packageManager.hasSystemFeature(PackageManager.FEATURE_CAMERA_FLASH)
-    }
-
-    @SuppressLint("NewApi") // since build() is not called if isAvailable() returned false
-    override fun build(ctx: SkillContext): Skill<*> {
-        return FlashlightSkill(FlashlightInfo, Sentences.Flashlight[ctx.sentencesLanguage]!!)
+    @SuppressLint("NewApi") // FlashlightSkill uses API 23+; guarded by FEATURE_CAMERA_FLASH check
+    override fun build(ctx: SkillContext): Skill<*>? {
+        val data = Sentences.Flashlight[ctx.sentencesLanguage] ?: return null
+        if (!ctx.android.packageManager.hasSystemFeature(PackageManager.FEATURE_CAMERA_FLASH))
+            return null
+        return FlashlightSkill(FlashlightInfo, data)
     }
 }

app/src/main/kotlin/org/stypox/dicio/skills/joke/JokeInfo.kt

@@ -23,12 +23,10 @@ object JokeInfo : SkillInfo("Joke") {
     override fun icon() =
         rememberVectorPainter(Icons.Default.EmojiEmotions)
 
-    override fun isAvailable(ctx: SkillContext): Boolean {
-        return (Sentences.Joke[ctx.sentencesLanguage] != null) &&
-                LocaleUtils.isLocaleSupported(ctx.locale, JokeSkill.JOKE_SUPPORTED_LOCALES)
-    }
-
-    override fun build(ctx: SkillContext): Skill<*> {
-        return JokeSkill(JokeInfo, Sentences.Joke[ctx.sentencesLanguage]!!)
+    override fun build(ctx: SkillContext): Skill<*>? {
+        val data = Sentences.Joke[ctx.sentencesLanguage] ?: return null
+        val locale = LocaleUtils.resolveSupportedLocale(ctx.locale, JokeSkill.JOKE_SUPPORTED_LOCALES)
+            ?: return null
+        return JokeSkill(JokeInfo, data, locale)
     }
 }

app/src/main/kotlin/org/stypox/dicio/skills/joke/JokeSkill.kt

@@ -8,24 +8,22 @@ import org.dicio.skill.standard.StandardRecognizerSkill
 import org.json.JSONObject
 import org.stypox.dicio.sentences.Sentences.Joke
 import org.stypox.dicio.util.ConnectionUtils
-import org.stypox.dicio.util.LocaleUtils
 
-class JokeSkill(correspondingSkillInfo: SkillInfo, data: StandardRecognizerData<Joke>)
-    : StandardRecognizerSkill<Joke>(correspondingSkillInfo, data) {
+class JokeSkill(
+    correspondingSkillInfo: SkillInfo,
+    data: StandardRecognizerData<Joke>,
+    private val resolvedLocale: String,
+) : StandardRecognizerSkill<Joke>(correspondingSkillInfo, data) {
     override suspend fun generateOutput(ctx: SkillContext, inputData: Joke): SkillOutput {
-        // we can use !! because the JokeInfo would have declared this skill unavailable
-        // if the current locale was not among the supported ones
-        val locale = LocaleUtils.resolveSupportedLocale(ctx.locale, JOKE_SUPPORTED_LOCALES)!!
-
-        if (locale == "en") {
+        if (resolvedLocale == "en") {
             val joke: JSONObject = ConnectionUtils.getPageJson(RANDOM_JOKE_URL_EN)
             return JokeOutput.Success(
                 setup = joke.getString("setup"),
                 delivery = joke.getString("punchline")
             )
         } else {
             val joke: JSONObject = ConnectionUtils.getPageJson(
-                "$RANDOM_JOKE_URL?lang=$locale&safe-mode&type=twopart"
+                "$RANDOM_JOKE_URL?lang=$resolvedLocale&safe-mode&type=twopart"
             )
             return JokeOutput.Success(
                 setup = joke.getString("setup"),

app/src/main/kotlin/org/stypox/dicio/skills/listening/ListeningInfo.kt

@@ -26,11 +26,8 @@ class ListeningInfo(
     override fun icon() =
         rememberVectorPainter(Icons.Default.Hearing)
 
-    override fun isAvailable(ctx: SkillContext): Boolean {
-        return Sentences.Listening[ctx.sentencesLanguage] != null
-    }
-
-    override fun build(ctx: SkillContext): Skill<*> {
-        return ListeningSkill(this, Sentences.Listening[ctx.sentencesLanguage]!!)
+    override fun build(ctx: SkillContext): Skill<*>? {
+        val data = Sentences.Listening[ctx.sentencesLanguage] ?: return null
+        return ListeningSkill(this, data)
     }
 }

app/src/main/kotlin/org/stypox/dicio/skills/lyrics/LyricsInfo.kt

@@ -22,11 +22,8 @@ object LyricsInfo : SkillInfo("lyrics") {
     override fun icon() =
         rememberVectorPainter(Icons.Default.MusicNote)
 
-    override fun isAvailable(ctx: SkillContext): Boolean {
-        return Sentences.Lyrics[ctx.sentencesLanguage] != null
-    }
-
-    override fun build(ctx: SkillContext): Skill<*> {
-        return LyricsSkill(LyricsInfo, Sentences.Lyrics[ctx.sentencesLanguage]!!)
+    override fun build(ctx: SkillContext): Skill<*>? {
+        val data = Sentences.Lyrics[ctx.sentencesLanguage] ?: return null
+        return LyricsSkill(LyricsInfo, data)
     }
 }

app/src/main/kotlin/org/stypox/dicio/skills/media/MediaInfo.kt

@@ -22,11 +22,8 @@ object MediaInfo : SkillInfo("media") {
     override fun icon() =
         rememberVectorPainter(Icons.AutoMirrored.Filled.QueueMusic)
 
-    override fun isAvailable(ctx: SkillContext): Boolean {
-        return Sentences.Media[ctx.sentencesLanguage] != null
-    }
-
-    override fun build(ctx: SkillContext): Skill<*> {
-        return MediaSkill(MediaInfo, Sentences.Media[ctx.sentencesLanguage]!!)
+    override fun build(ctx: SkillContext): Skill<*>? {
+        val data = Sentences.Media[ctx.sentencesLanguage] ?: return null
+        return MediaSkill(MediaInfo, data)
     }
 }

app/src/main/kotlin/org/stypox/dicio/skills/navigation/NavigationInfo.kt

@@ -25,11 +25,8 @@ object NavigationInfo : SkillInfo("navigation") {
     override fun icon() =
         rememberVectorPainter(Icons.Default.Directions)
 
-    override fun isAvailable(ctx: SkillContext): Boolean {
-        return Sentences.Navigation[ctx.sentencesLanguage] != null
-    }
-
-    override fun build(ctx: SkillContext): Skill<*> {
-        return NavigationSkill(NavigationInfo, Sentences.Navigation[ctx.sentencesLanguage]!!)
+    override fun build(ctx: SkillContext): Skill<*>? {
+        val data = Sentences.Navigation[ctx.sentencesLanguage] ?: return null
+        return NavigationSkill(NavigationInfo, data)
     }
 }

app/src/main/kotlin/org/stypox/dicio/skills/notify/NotifyInfo.kt

@@ -24,14 +24,11 @@ object NotifyInfo: SkillInfo("notify") {
     override fun icon() =
         rememberVectorPainter(Icons.Default.NotificationsActive)
 
-    override fun isAvailable(ctx: SkillContext): Boolean {
-        return Sentences.Notify[ctx.sentencesLanguage] != null
-    }
-
     override val neededPermissions: List<Permission>
             = listOf(PERMISSION_NOTIFICATION_LISTENER)
 
-    override fun build(ctx: SkillContext): Skill<*> {
-        return NotifySkill(NotifyInfo, Sentences.Notify[ctx.sentencesLanguage]!!)
+    override fun build(ctx: SkillContext): Skill<*>? {
+        val data = Sentences.Notify[ctx.sentencesLanguage] ?: return null
+        return NotifySkill(NotifyInfo, data)
     }
 }

app/src/main/kotlin/org/stypox/dicio/skills/open/OpenInfo.kt

@@ -25,11 +25,8 @@ object OpenInfo : SkillInfo("open") {
     override fun icon() =
         rememberVectorPainter(Icons.AutoMirrored.Filled.OpenInNew)
 
-    override fun isAvailable(ctx: SkillContext): Boolean {
-        return Sentences.Open[ctx.sentencesLanguage] != null
-    }
-
-    override fun build(ctx: SkillContext): Skill<*> {
-        return OpenSkill(OpenInfo, Sentences.Open[ctx.sentencesLanguage]!!)
+    override fun build(ctx: SkillContext): Skill<*>? {
+        val data = Sentences.Open[ctx.sentencesLanguage] ?: return null
+        return OpenSkill(OpenInfo, data)
     }
 }

app/src/main/kotlin/org/stypox/dicio/skills/search/SearchInfo.kt

@@ -22,11 +22,8 @@ object SearchInfo : SkillInfo("search") {
     override fun icon() =
         rememberVectorPainter(Icons.Default.Search)
 
-    override fun isAvailable(ctx: SkillContext): Boolean {
-        return Sentences.Search[ctx.sentencesLanguage] != null
-    }
-
-    override fun build(ctx: SkillContext): Skill<*> {
-        return SearchSkill(SearchInfo, Sentences.Search[ctx.sentencesLanguage]!!)
+    override fun build(ctx: SkillContext): Skill<*>? {
+        val data = Sentences.Search[ctx.sentencesLanguage] ?: return null
+        return SearchSkill(SearchInfo, data)
     }
 }

app/src/main/kotlin/org/stypox/dicio/skills/telephone/ConfirmCallOutput.kt

@@ -9,6 +9,7 @@ import androidx.compose.ui.unit.dp
 import org.dicio.skill.context.SkillContext
 import org.dicio.skill.skill.InteractionPlan
 import org.dicio.skill.skill.SkillOutput
+import org.dicio.skill.standard.StandardRecognizerData
 import org.stypox.dicio.R
 import org.stypox.dicio.io.graphical.Body
 import org.stypox.dicio.io.graphical.Headline
@@ -18,14 +19,14 @@ import org.stypox.dicio.util.getString
 
 class ConfirmCallOutput(
     private val name: String,
-    private val number: String
+    private val number: String,
+    private val yesNoData: StandardRecognizerData<Sentences.UtilYesNo>,
 ) : SkillOutput {
     override fun getSpeechOutput(ctx: SkillContext): String =
         ctx.getString(R.string.skill_telephone_confirm_call, name)
 
     override fun getInteractionPlan(ctx: SkillContext): InteractionPlan {
-        val yesNoSentences = Sentences.UtilYesNo[ctx.sentencesLanguage]!!
-        val confirmYesNoSkill = object : RecognizeYesNoSkill(TelephoneInfo, yesNoSentences) {
+        val confirmYesNoSkill = object : RecognizeYesNoSkill(TelephoneInfo, yesNoData) {
             override suspend fun generateOutput(
                 ctx: SkillContext,
                 inputData: Boolean

app/src/main/kotlin/org/stypox/dicio/skills/telephone/ContactChooserIndex.kt

@@ -8,8 +8,13 @@ import org.dicio.skill.skill.Skill
 import org.dicio.skill.skill.SkillOutput
 import org.dicio.skill.skill.Specificity
 
-class ContactChooserIndex internal constructor(private val contacts: List<Pair<String, String>>) :
-    Skill<Int>(TelephoneInfo, Specificity.HIGH) {
+import org.dicio.skill.standard.StandardRecognizerData
+import org.stypox.dicio.sentences.Sentences
+
+class ContactChooserIndex internal constructor(
+    private val contacts: List<Pair<String, String>>,
+    private val yesNoData: StandardRecognizerData<Sentences.UtilYesNo>,
+) : Skill<Int>(TelephoneInfo, Specificity.HIGH) {
 
     override fun score(
         ctx: SkillContext,
@@ -29,7 +34,7 @@ class ContactChooserIndex internal constructor(private val contacts: List<Pair<S
     override suspend fun generateOutput(ctx: SkillContext, inputData: Int): SkillOutput {
         if (inputData > 0 && inputData <= contacts.size) {
             val contact = contacts[inputData - 1]
-            return ConfirmCallOutput(contact.first, contact.second)
+            return ConfirmCallOutput(contact.first, contact.second, yesNoData)
         } else {
             // impossible situation
             return ConfirmedCallOutput(null)

app/src/main/kotlin/org/stypox/dicio/skills/telephone/ContactChooserName.kt

@@ -7,9 +7,14 @@ import org.dicio.skill.skill.Score
 import org.dicio.skill.skill.Skill
 import org.dicio.skill.skill.SkillOutput
 import org.dicio.skill.skill.Specificity
+import org.dicio.skill.standard.StandardRecognizerData
+import org.stypox.dicio.sentences.Sentences
 import org.stypox.dicio.util.StringUtils
 
-class ContactChooserName internal constructor(private val contacts: List<Pair<String, String>>) :
+class ContactChooserName internal constructor(
+    private val contacts: List<Pair<String, String>>,
+    private val yesNoData: StandardRecognizerData<Sentences.UtilYesNo>,
+) :
     // use a low specificity to prefer the index-based contact chooser
     Skill<Pair<String, String>?>(TelephoneInfo, Specificity.LOW) {
 
@@ -38,7 +43,7 @@ class ContactChooserName internal constructor(private val contacts: List<Pair<St
 
     override suspend fun generateOutput(ctx: SkillContext, inputData: Pair<String, String>?): SkillOutput {
         return inputData?.let {
-            ConfirmCallOutput(it.first, it.second)
+            ConfirmCallOutput(it.first, it.second, yesNoData)
         }
             // impossible situation
             ?: ConfirmedCallOutput(null)