[Paywalls V2] Moves validation logic to the Loading phase (#2007)

ui/revenuecatui/src/main/kotlin/com/revenuecat/purchases/ui/revenuecatui/components/button/ButtonComponentView.kt

@@ -45,7 +45,10 @@ import com.revenuecat.purchases.ui.revenuecatui.components.style.ButtonComponent
 import com.revenuecat.purchases.ui.revenuecatui.components.style.StackComponentStyle
 import com.revenuecat.purchases.ui.revenuecatui.components.style.TextComponentStyle
 import com.revenuecat.purchases.ui.revenuecatui.data.PaywallState
+import com.revenuecat.purchases.ui.revenuecatui.helpers.getOrThrow
 import com.revenuecat.purchases.ui.revenuecatui.helpers.nonEmptyMapOf
+import com.revenuecat.purchases.ui.revenuecatui.helpers.toComponentsPaywallState
+import com.revenuecat.purchases.ui.revenuecatui.helpers.validate
 import kotlinx.coroutines.launch
 import java.net.URL
 
@@ -148,5 +151,5 @@ private fun previewEmptyState(): PaywallState.Loaded.Components {
         paywallComponents = data,
     )
 
-    return PaywallState.Loaded.Components(offering, data)
+    return offering.toComponentsPaywallState(data.validate().getOrThrow())
 }

ui/revenuecatui/src/main/kotlin/com/revenuecat/purchases/ui/revenuecatui/components/stack/StackComponentView.kt

@@ -58,7 +58,10 @@ import com.revenuecat.purchases.ui.revenuecatui.components.style.StackComponentS
 import com.revenuecat.purchases.ui.revenuecatui.components.style.TextComponentStyle
 import com.revenuecat.purchases.ui.revenuecatui.data.PaywallState
 import com.revenuecat.purchases.ui.revenuecatui.extensions.applyIfNotNull
+import com.revenuecat.purchases.ui.revenuecatui.helpers.getOrThrow
 import com.revenuecat.purchases.ui.revenuecatui.helpers.nonEmptyMapOf
+import com.revenuecat.purchases.ui.revenuecatui.helpers.toComponentsPaywallState
+import com.revenuecat.purchases.ui.revenuecatui.helpers.validate
 import java.net.URL
 
 @Suppress("LongMethod")
@@ -336,5 +339,5 @@ private fun previewEmptyState(): PaywallState.Loaded.Components {
         paywallComponents = data,
     )
 
-    return PaywallState.Loaded.Components(offering, data)
+    return offering.toComponentsPaywallState(data.validate().getOrThrow())
 }

ui/revenuecatui/src/main/kotlin/com/revenuecat/purchases/ui/revenuecatui/components/text/TextComponentView.kt

@@ -50,8 +50,11 @@ import com.revenuecat.purchases.ui.revenuecatui.data.PaywallState
 import com.revenuecat.purchases.ui.revenuecatui.data.processed.VariableDataProvider
 import com.revenuecat.purchases.ui.revenuecatui.data.processed.VariableProcessor
 import com.revenuecat.purchases.ui.revenuecatui.extensions.applyIfNotNull
+import com.revenuecat.purchases.ui.revenuecatui.helpers.getOrThrow
 import com.revenuecat.purchases.ui.revenuecatui.helpers.nonEmptyMapOf
+import com.revenuecat.purchases.ui.revenuecatui.helpers.toComponentsPaywallState
 import com.revenuecat.purchases.ui.revenuecatui.helpers.toResourceProvider
+import com.revenuecat.purchases.ui.revenuecatui.helpers.validate
 import java.net.URL
 
 @Composable
@@ -414,5 +417,5 @@ private fun previewEmptyState(): PaywallState.Loaded.Components {
         paywallComponents = data,
     )
 
-    return PaywallState.Loaded.Components(offering, data)
+    return offering.toComponentsPaywallState(data.validate().getOrThrow())
 }

ui/revenuecatui/src/main/kotlin/com/revenuecat/purchases/ui/revenuecatui/data/PaywallState.kt

@@ -11,13 +11,15 @@ import androidx.compose.runtime.setValue
 import androidx.compose.ui.text.intl.LocaleList
 import com.revenuecat.purchases.Offering
 import com.revenuecat.purchases.Package
+import com.revenuecat.purchases.paywalls.components.common.Background
 import com.revenuecat.purchases.paywalls.components.common.LocaleId
-import com.revenuecat.purchases.paywalls.components.common.PaywallComponentsData
 import com.revenuecat.purchases.ui.revenuecatui.components.ktx.toComposeLocale
 import com.revenuecat.purchases.ui.revenuecatui.components.ktx.toLocaleId
+import com.revenuecat.purchases.ui.revenuecatui.components.style.ComponentStyle
 import com.revenuecat.purchases.ui.revenuecatui.data.processed.ProcessedLocalizedConfiguration
 import com.revenuecat.purchases.ui.revenuecatui.data.processed.TemplateConfiguration
 import com.revenuecat.purchases.ui.revenuecatui.helpers.Logger
+import com.revenuecat.purchases.ui.revenuecatui.helpers.NonEmptySet
 import com.revenuecat.purchases.ui.revenuecatui.isFullScreen
 import android.os.LocaleList as FrameworkLocaleList
 
@@ -58,10 +60,17 @@ internal sealed interface PaywallState {
             }
         }
 
+        @Suppress("LongParameterList")
         @Stable
         class Components(
+            val stack: ComponentStyle,
+            val stickyFooter: ComponentStyle?,
+            val background: Background,
             override val offering: Offering,
-            val data: PaywallComponentsData,
+            /**
+             * All locales that this paywall supports, with `locales.head` being the default one.
+             */
+            private val locales: NonEmptySet<LocaleId>,
             initialLocaleList: LocaleList = LocaleList.current,
             initialIsEligibleForIntroOffer: Boolean = false,
             initialSelectedPackage: Package? = null,
@@ -90,9 +99,9 @@ internal sealed interface PaywallState {
 
             private fun LocaleList.toLocaleId(): LocaleId =
                 // Configured locales take precedence over the default one.
-                map { it.toLocaleId() }.plus(data.defaultLocaleIdentifier)
+                map { it.toLocaleId() }.plus(locales.head)
                     // Find the first locale we have a LocalizationDictionary for.
-                    .first { id -> data.componentsLocalizations.containsKey(id) }
+                    .first { id -> locales.contains(id) }
 
             private fun List<Package>.mostExpensivePricePerMonthMicros(): Long? =
                 asSequence()

ui/revenuecatui/src/main/kotlin/com/revenuecat/purchases/ui/revenuecatui/data/PaywallViewModel.kt

@@ -31,7 +31,7 @@ import com.revenuecat.purchases.ui.revenuecatui.helpers.PaywallValidationResult
 import com.revenuecat.purchases.ui.revenuecatui.helpers.ResourceProvider
 import com.revenuecat.purchases.ui.revenuecatui.helpers.toComponentsPaywallState
 import com.revenuecat.purchases.ui.revenuecatui.helpers.toLegacyPaywallState
-import com.revenuecat.purchases.ui.revenuecatui.helpers.validatedLegacyPaywall
+import com.revenuecat.purchases.ui.revenuecatui.helpers.validatedPaywall
 import com.revenuecat.purchases.ui.revenuecatui.strings.PaywallValidationErrorStrings
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.StateFlow
@@ -374,13 +374,12 @@ internal class PaywallViewModelImpl(
             return PaywallState.Error("No packages available")
         }
 
-        val validationResult = offering.paywallComponents
-            // TODO Actually validate the PaywallComponentsData
-            ?.let { PaywallValidationResult.Components(displayablePaywall = it) }
-            ?: offering.validatedLegacyPaywall(colorScheme, resourceProvider)
+        val validationResult = offering.validatedPaywall(colorScheme, resourceProvider)
 
-        validationResult.error?.let { validationError ->
-            Logger.w(validationError.associatedErrorString(offering))
+        validationResult.errors?.let { validationErrors ->
+            validationErrors.forEach { error ->
+                Logger.w(error.associatedErrorString(offering))
+            }
             Logger.w(PaywallValidationErrorStrings.DISPLAYING_DEFAULT)
         }
 
@@ -398,7 +397,7 @@ internal class PaywallViewModelImpl(
                 storefrontCountryCode = storefrontCountryCode,
             )
             is PaywallValidationResult.Components -> offering.toComponentsPaywallState(
-                validatedPaywallData = validationResult.displayablePaywall,
+                validationResult = validationResult,
             )
         }
     }

ui/revenuecatui/src/main/kotlin/com/revenuecat/purchases/ui/revenuecatui/errors/PaywallValidationError.kt

@@ -28,6 +28,7 @@ internal sealed class PaywallValidationError : Throwable() {
             }
             is MissingStringLocalization -> message
             is MissingImageLocalization -> message
+            is AllLocalizationsMissing -> message
         }
     }
 
@@ -53,4 +54,10 @@ internal sealed class PaywallValidationError : Throwable() {
             PaywallValidationErrorStrings.MISSING_IMAGE_LOCALIZATION_WITH_LOCALE.format(key.value, locale.value)
         } ?: PaywallValidationErrorStrings.MISSING_IMAGE_LOCALIZATION.format(key.value)
     }
+    data class AllLocalizationsMissing(
+        val locale: LocaleId,
+    ) : PaywallValidationError() {
+        override val message: String =
+            PaywallValidationErrorStrings.ALL_LOCALIZATIONS_MISSING_FOR_LOCALE.format(locale.value)
+    }
 }

ui/revenuecatui/src/main/kotlin/com/revenuecat/purchases/ui/revenuecatui/helpers/NonEmptyMap.kt

@@ -13,6 +13,8 @@ internal class NonEmptyMap<K, out V> private constructor(
 
     constructor(entry: Pair<K, V>, tail: Map<K, V>) : this(entry = mapOf(entry).entries.first(), all = tail + entry)
 
+    override val keys: NonEmptySet<K> = NonEmptySet(entry.key, all.keys)
+
     @JvmSynthetic
     fun toMap(): Map<K, V> = all
 

ui/revenuecatui/src/main/kotlin/com/revenuecat/purchases/ui/revenuecatui/helpers/NonEmptySet.kt

@@ -0,0 +1,43 @@
+@file:JvmSynthetic
+
+package com.revenuecat.purchases.ui.revenuecatui.helpers
+
+/**
+ * A Set that is guaranteed to have at least 1 element. Inspired by Arrow. Use [nonEmptySetOf] or
+ * [toNonEmptySetOrNull] to construct.
+ */
+internal class NonEmptySet<out A> private constructor(
+    @get:JvmSynthetic
+    val head: A,
+    private val all: Set<A>,
+) : Set<A> by all {
+
+    constructor(head: A, rest: Iterable<A>) : this(head, all = rest.toSet() + head)
+
+    @JvmSynthetic
+    fun toSet(): Set<A> = all
+
+    @JvmSynthetic
+    override fun isEmpty(): Boolean = false
+
+    override fun equals(other: Any?): Boolean = when (other) {
+        is NonEmptySet<*> -> this.all == other.all
+        else -> this.all == other
+    }
+
+    override fun hashCode(): Int = all.hashCode()
+
+    override fun toString(): String =
+        "NonEmptySet(${all.joinToString()})"
+}
+
+@JvmSynthetic
+internal fun <A> nonEmptySetOf(head: A, vararg t: A): NonEmptySet<A> =
+    NonEmptySet(head, t.asIterable())
+
+@JvmSynthetic
+internal fun <A> Iterable<A>.toNonEmptySetOrNull(): NonEmptySet<A>? {
+    val iterator = iterator()
+    if (!iterator.hasNext()) return null
+    return NonEmptySet(iterator.next(), Iterable { iterator })
+}

ui/revenuecatui/src/main/kotlin/com/revenuecat/purchases/ui/revenuecatui/helpers/OfferingToStateMapper.kt

@@ -1,10 +1,16 @@
+@file:Suppress("TooManyFunctions")
+
 package com.revenuecat.purchases.ui.revenuecatui.helpers
 
 import androidx.compose.material3.ColorScheme
 import com.revenuecat.purchases.Offering
 import com.revenuecat.purchases.paywalls.PaywallData
+import com.revenuecat.purchases.paywalls.components.common.LocalizationData
+import com.revenuecat.purchases.paywalls.components.common.LocalizationKey
 import com.revenuecat.purchases.paywalls.components.common.PaywallComponentsData
 import com.revenuecat.purchases.ui.revenuecatui.PaywallMode
+import com.revenuecat.purchases.ui.revenuecatui.components.PaywallAction
+import com.revenuecat.purchases.ui.revenuecatui.components.style.StyleFactory
 import com.revenuecat.purchases.ui.revenuecatui.composables.PaywallIconName
 import com.revenuecat.purchases.ui.revenuecatui.data.PaywallState
 import com.revenuecat.purchases.ui.revenuecatui.data.processed.PackageConfigurationType
@@ -17,27 +23,30 @@ import com.revenuecat.purchases.ui.revenuecatui.extensions.createDefault
 import com.revenuecat.purchases.ui.revenuecatui.extensions.createDefaultForIdentifiers
 import com.revenuecat.purchases.ui.revenuecatui.extensions.defaultTemplate
 import kotlin.Result
+import com.revenuecat.purchases.ui.revenuecatui.helpers.Result as RcResult
 
 @Suppress("ReturnCount")
-internal fun Offering.validatedLegacyPaywall(
+internal fun Offering.validatedPaywall(
     currentColorScheme: ColorScheme,
     resourceProvider: ResourceProvider,
-): PaywallValidationResult.Legacy {
-    val paywallData = this.paywall
-        ?: return PaywallValidationResult.Legacy(
-            PaywallData.createDefault(
-                availablePackages,
-                currentColorScheme,
-                resourceProvider,
-            ),
-            PaywallData.defaultTemplate,
-            PaywallValidationError.MissingPaywall,
-        )
+): PaywallValidationResult =
+    paywallComponents?.validate()?.let { result ->
+        // We need to either unwrap the success value, or wrap the errors in a fallback Paywall.
+        when (result) {
+            is RcResult.Success -> result.value
+            is RcResult.Error -> fallbackPaywall(currentColorScheme, resourceProvider, errors = result.value)
+        }
+    } ?: paywall?.validate(currentColorScheme, resourceProvider)
+        ?: fallbackPaywall(currentColorScheme, resourceProvider, error = PaywallValidationError.MissingPaywall)
 
-    val template = paywallData.validate().getOrElse {
+internal fun PaywallData.validate(
+    currentColorScheme: ColorScheme,
+    resourceProvider: ResourceProvider,
+): PaywallValidationResult.Legacy {
+    val template = validate().getOrElse {
         return PaywallValidationResult.Legacy(
             PaywallData.createDefaultForIdentifiers(
-                paywallData.config.packageIds,
+                config.packageIds,
                 currentColorScheme,
                 resourceProvider,
             ),
@@ -46,11 +55,72 @@ internal fun Offering.validatedLegacyPaywall(
         )
     }
     return PaywallValidationResult.Legacy(
-        paywallData,
+        this,
         template,
     )
 }
 
+private fun Offering.fallbackPaywall(
+    currentColorScheme: ColorScheme,
+    resourceProvider: ResourceProvider,
+    error: PaywallValidationError,
+): PaywallValidationResult.Legacy =
+    fallbackPaywall(
+        currentColorScheme = currentColorScheme,
+        resourceProvider = resourceProvider,
+        errors = nonEmptyListOf(error),
+    )
+
+private fun Offering.fallbackPaywall(
+    currentColorScheme: ColorScheme,
+    resourceProvider: ResourceProvider,
+    errors: NonEmptyList<PaywallValidationError>,
+): PaywallValidationResult.Legacy =
+    PaywallValidationResult.Legacy(
+        PaywallData.createDefault(
+            availablePackages,
+            currentColorScheme,
+            resourceProvider,
+        ),
+        PaywallData.defaultTemplate,
+        errors,
+    )
+
+@Suppress("MaxLineLength")
+internal fun PaywallComponentsData.validate(): RcResult<PaywallValidationResult.Components, NonEmptyList<PaywallValidationError>> =
+    defaultLocalization
+        // Check that the default localization is present in the localizations map.
+        .errorIfNull(PaywallValidationError.AllLocalizationsMissing(defaultLocaleIdentifier))
+        .mapError { nonEmptyListOf(it) }
+        .map { defaultLocalization ->
+            // Build a NonEmptyMap, ensuring that we always have the default localization as fallback.
+            nonEmptyMapOf(defaultLocaleIdentifier to defaultLocalization, componentsLocalizations)
+        }
+        .flatMap { localizations ->
+            // We need to turn our NonEmptyMap<LocaleId, Map> into NonEmptyMap<LocaleId, NonEmptyMap>.
+            localizations.mapValues { (locale, map) ->
+                map.toNonEmptyMapOrNull()
+                    .errorIfNull(PaywallValidationError.AllLocalizationsMissing(locale))
+                    .mapError { nonEmptyListOf(it) }
+            }.mapValuesOrAccumulate { it }
+        }.flatMap { localizations ->
+            // Use the StyleFactory to recursively create and validate all ComponentStyles.
+            val styleFactory = StyleFactory(localizations)
+            val actionHandler: suspend (PaywallAction) -> Unit = { /* TODO Move the action handler to the UI layer. */ }
+            val config = componentsConfig.base
+            zipOrAccumulate(
+                styleFactory.create(config.stack, actionHandler),
+                config.stickyFooter?.let { styleFactory.create(it, actionHandler) }.orSuccessfullyNull(),
+            ) { stack, stickyFooter ->
+                PaywallValidationResult.Components(
+                    stack = stack,
+                    stickyFooter = stickyFooter,
+                    background = config.background,
+                    locales = localizations.keys,
+                )
+            }
+        }
+
 @Suppress("ReturnCount")
 private fun PaywallData.validate(): Result<PaywallTemplate> {
     val template = validateTemplate() ?: return Result.failure(PaywallValidationError.InvalidTemplate(templateName))
@@ -162,10 +232,15 @@ internal fun Offering.toLegacyPaywallState(
     )
 }
 
-internal fun Offering.toComponentsPaywallState(validatedPaywallData: PaywallComponentsData): PaywallState =
+internal fun Offering.toComponentsPaywallState(
+    validationResult: PaywallValidationResult.Components,
+): PaywallState.Loaded.Components =
     PaywallState.Loaded.Components(
+        stack = validationResult.stack,
+        stickyFooter = validationResult.stickyFooter,
+        background = validationResult.background,
         offering = this,
-        data = validatedPaywallData,
+        locales = validationResult.locales,
     )
 
 /**
@@ -222,3 +297,6 @@ private fun PaywallData.LocalizedConfiguration.validateIcons(): PaywallValidatio
 private fun PaywallData.validateTemplate(): PaywallTemplate? {
     return PaywallTemplate.fromId(templateName)
 }
+
+private val PaywallComponentsData.defaultLocalization: Map<LocalizationKey, LocalizationData>?
+    get() = componentsLocalizations[defaultLocaleIdentifier]