Add the add-translation workflow from the artifact detail screen

An Add Translation button in the artifact detail's Translations section opens a workflow that requires selecting or creating a dialect (reusing the chip picker + create-new-dialect fields), then scaffolds the translation. - MantraRepository.addTranslation creates a MantraTranslationArtifactVersion for the artifact's latest version and the chosen dialectId (inheriting the source artifact's name/visibility/license), then mirrors the source structure: a MantraTranslationChapter per chapter and a MantraTranslationChunk (empty text scaffold) per chunk. Each created entity also gets a MarmotInnerEvent rumor (kinds 30306/30308/30309). When a new dialect is requested the ViewModel creates it first via addDialect. - The three translation events' build methods now take real fields (fixing their phantom generics); toXEvent tag order matches build and fromXEventTemplate companions are added so the event ids round-trip. - New AddTranslationScreen (route + ViewModel + UIState). On success it lands on a freshly-loaded artifact detail via popUpTo<ArtifactDetailRoute>. No MantraTranslation rows / translation text are created here — that is the per-chunk authoring step, intentionally left out. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-07-26 01:52:15 +02:00
parent b2664bf7a5
commit 99f99fa959
14 changed files with 739 additions and 13 deletions
--- a/composeApp/src/commonMain/kotlin/press/mantra/compose/database/model/MantraTranslationArtifactVersion.kt
+++ b/composeApp/src/commonMain/kotlin/press/mantra/compose/database/model/MantraTranslationArtifactVersion.kt
@@ -5,9 +5,11 @@ import androidx.room3.ForeignKey
 import androidx.room3.PrimaryKey
 import com.vitorpamplona.quartz.nip01Core.core.HexKey
 import com.vitorpamplona.quartz.nip01Core.core.TagArrayBuilder
+import com.vitorpamplona.quartz.nip01Core.crypto.EventHasher
+import com.vitorpamplona.quartz.nip01Core.signers.EventTemplate
+import com.vitorpamplona.quartz.nip31Alts.AltTag
 import press.mantra.compose.database.model.traits.OptionalNostrEventEntity
 import press.mantra.compose.database.model.traits.TimestampedEntity
-import press.mantra.compose.nostr.nip30303.ArtifactVersionEvent
 import press.mantra.compose.nostr.nip30303.TranslationArtifactVersionEvent
 import press.mantra.compose.nostr.nip30303.tags.ArtifactVersionIdTag
 import press.mantra.compose.nostr.nip30303.tags.DialectIdTag
@@ -75,7 +77,9 @@ data class MantraTranslationArtifactVersion(
            id = id,
            pubKey = publicKey,
            createdAt = createdAt.epochSeconds,
-            tags = TagArrayBuilder<ArtifactVersionEvent>()
+            // Tag order matches TranslationArtifactVersionEvent.build so the id round-trips.
+            tags = TagArrayBuilder<TranslationArtifactVersionEvent>()
+                .addUnique(AltTag.assemble(TranslationArtifactVersionEvent.ALT_DESCRIPTION))
                .addUnique(
                    ArtifactVersionIdTag.assemble(artifactVersionId)
                )
@@ -92,6 +96,30 @@ data class MantraTranslationArtifactVersion(
    }

    companion object {
+        fun fromTranslationArtifactVersionEventTemplate(
+            translationArtifactVersionEventTemplate: EventTemplate<TranslationArtifactVersionEvent>,
+            chatRoomId: HexKey,
+            userPublicKey: HexKey,
+        ): MantraTranslationArtifactVersion? {
+            return fromTranslationArtifactVersionEvent(
+                TranslationArtifactVersionEvent(
+                    id = EventHasher.hashId(
+                        pubKey = userPublicKey,
+                        tags = translationArtifactVersionEventTemplate.tags,
+                        content = translationArtifactVersionEventTemplate.content,
+                        createdAt = translationArtifactVersionEventTemplate.createdAt,
+                        kind = translationArtifactVersionEventTemplate.kind,
+                    ),
+                    content = translationArtifactVersionEventTemplate.content,
+                    tags = translationArtifactVersionEventTemplate.tags,
+                    createdAt = translationArtifactVersionEventTemplate.createdAt,
+                    pubKey = userPublicKey,
+                    sig = "", // Unsigned rumor
+                ),
+                chatRoomId = chatRoomId,
+            )
+        }
+
        fun fromTranslationArtifactVersionEvent(translationArtifactVersionEvent: TranslationArtifactVersionEvent, chatRoomId: HexKey): MantraTranslationArtifactVersion? {

            return translationArtifactVersionEvent.artifactVersionId()?.let { artifactVersionId ->
--- a/composeApp/src/commonMain/kotlin/press/mantra/compose/database/model/MantraTranslationChapter.kt
+++ b/composeApp/src/commonMain/kotlin/press/mantra/compose/database/model/MantraTranslationChapter.kt
@@ -5,9 +5,11 @@ import androidx.room3.ForeignKey
 import androidx.room3.PrimaryKey
 import com.vitorpamplona.quartz.nip01Core.core.HexKey
 import com.vitorpamplona.quartz.nip01Core.core.TagArrayBuilder
+import com.vitorpamplona.quartz.nip01Core.crypto.EventHasher
+import com.vitorpamplona.quartz.nip01Core.signers.EventTemplate
+import com.vitorpamplona.quartz.nip31Alts.AltTag
 import press.mantra.compose.database.model.traits.OptionalNostrEventEntity
 import press.mantra.compose.database.model.traits.TimestampedEntity
-import press.mantra.compose.nostr.nip30303.ChapterEvent
 import press.mantra.compose.nostr.nip30303.TranslationChapterEvent
 import press.mantra.compose.nostr.nip30303.tags.ChapterIdTag
 import press.mantra.compose.nostr.nip30303.tags.IndexTag
@@ -70,7 +72,9 @@ data class MantraTranslationChapter(
            id = id,
            pubKey = publicKey,
            createdAt = createdAt.epochSeconds,
+            // Tag order matches TranslationChapterEvent.build so the id round-trips.
            tags = TagArrayBuilder<TranslationChapterEvent>()
+                .addUnique(AltTag.assemble(TranslationChapterEvent.ALT_DESCRIPTION))
                .addUnique(
                    TranslationArtifactVersionIdTag.assemble(translationArtifactVersionId)
                )
@@ -87,6 +91,30 @@ data class MantraTranslationChapter(
    }

    companion object {
+        fun fromTranslationChapterEventTemplate(
+            translationChapterEventTemplate: EventTemplate<TranslationChapterEvent>,
+            chatRoomId: HexKey,
+            userPublicKey: HexKey,
+        ): MantraTranslationChapter? {
+            return fromTranslationChapterEvent(
+                TranslationChapterEvent(
+                    id = EventHasher.hashId(
+                        pubKey = userPublicKey,
+                        tags = translationChapterEventTemplate.tags,
+                        content = translationChapterEventTemplate.content,
+                        createdAt = translationChapterEventTemplate.createdAt,
+                        kind = translationChapterEventTemplate.kind,
+                    ),
+                    content = translationChapterEventTemplate.content,
+                    tags = translationChapterEventTemplate.tags,
+                    createdAt = translationChapterEventTemplate.createdAt,
+                    pubKey = userPublicKey,
+                    sig = "", // Unsigned rumor
+                ),
+                chatRoomId = chatRoomId,
+            )
+        }
+
        fun fromTranslationChapterEvent(translationChapterEvent: TranslationChapterEvent, chatRoomId: HexKey): MantraTranslationChapter? {
            return translationChapterEvent.chapterId()?.let { chapterId ->
                translationChapterEvent.translationArtifactVersionId()?.let { translationArtifactVersionId ->
--- a/composeApp/src/commonMain/kotlin/press/mantra/compose/database/model/MantraTranslationChunk.kt
+++ b/composeApp/src/commonMain/kotlin/press/mantra/compose/database/model/MantraTranslationChunk.kt
@@ -5,9 +5,11 @@ import androidx.room3.ForeignKey
 import androidx.room3.PrimaryKey
 import com.vitorpamplona.quartz.nip01Core.core.HexKey
 import com.vitorpamplona.quartz.nip01Core.core.TagArrayBuilder
+import com.vitorpamplona.quartz.nip01Core.crypto.EventHasher
+import com.vitorpamplona.quartz.nip01Core.signers.EventTemplate
+import com.vitorpamplona.quartz.nip31Alts.AltTag
 import press.mantra.compose.database.model.traits.OptionalNostrEventEntity
 import press.mantra.compose.database.model.traits.TimestampedEntity
-import press.mantra.compose.nostr.nip30303.ChunkEvent
 import press.mantra.compose.nostr.nip30303.TranslationChunkEvent
 import press.mantra.compose.nostr.nip30303.tags.ChunkIdTag
 import press.mantra.compose.nostr.nip30303.tags.IndexTag
@@ -72,7 +74,9 @@ data class MantraTranslationChunk(
            id = id,
            pubKey = publicKey,
            createdAt = createdAt.epochSeconds,
+            // Tag order matches TranslationChunkEvent.build so the id round-trips.
            tags = TagArrayBuilder<TranslationChunkEvent>()
+                .addUnique(AltTag.assemble(TranslationChunkEvent.ALT_DESCRIPTION))
                .addUnique(
                    TranslationChapterIdTag.assemble(translationChapterId)
                )
@@ -89,6 +93,30 @@ data class MantraTranslationChunk(
    }

    companion object {
+        fun fromTranslationChunkEventTemplate(
+            translationChunkEventTemplate: EventTemplate<TranslationChunkEvent>,
+            chatRoomId: HexKey,
+            userPublicKey: HexKey,
+        ): MantraTranslationChunk? {
+            return fromTranslationChunkEvent(
+                TranslationChunkEvent(
+                    id = EventHasher.hashId(
+                        pubKey = userPublicKey,
+                        tags = translationChunkEventTemplate.tags,
+                        content = translationChunkEventTemplate.content,
+                        createdAt = translationChunkEventTemplate.createdAt,
+                        kind = translationChunkEventTemplate.kind,
+                    ),
+                    content = translationChunkEventTemplate.content,
+                    tags = translationChunkEventTemplate.tags,
+                    createdAt = translationChunkEventTemplate.createdAt,
+                    pubKey = userPublicKey,
+                    sig = "", // Unsigned rumor
+                ),
+                chatRoomId = chatRoomId,
+            )
+        }
+
        fun fromTranslationChunkEvent(translationChunkEvent: TranslationChunkEvent, chatRoomId: HexKey): MantraTranslationChunk? {
            return translationChunkEvent.translationChapterId()?.let { translationChapterId ->
                translationChunkEvent.chunkId()?.let { chunkId ->
--- a/composeApp/src/commonMain/kotlin/press/mantra/compose/database/repository/DatabaseMantraRepository.kt
+++ b/composeApp/src/commonMain/kotlin/press/mantra/compose/database/repository/DatabaseMantraRepository.kt
@@ -10,12 +10,17 @@ import press.mantra.compose.database.model.MantraChapter
 import press.mantra.compose.database.model.MantraChunk
 import press.mantra.compose.database.model.MantraDialect
 import press.mantra.compose.database.model.MantraTranslationArtifactVersion
+import press.mantra.compose.database.model.MantraTranslationChapter
+import press.mantra.compose.database.model.MantraTranslationChunk
 import press.mantra.compose.database.model.MarmotInnerEvent
 import press.mantra.compose.nostr.nip30303.ArtifactEvent
 import press.mantra.compose.nostr.nip30303.ArtifactVersionEvent
 import press.mantra.compose.nostr.nip30303.ChapterEvent
 import press.mantra.compose.nostr.nip30303.ChunkEvent
 import press.mantra.compose.nostr.nip30303.DialectEvent
+import press.mantra.compose.nostr.nip30303.TranslationArtifactVersionEvent
+import press.mantra.compose.nostr.nip30303.TranslationChapterEvent
+import press.mantra.compose.nostr.nip30303.TranslationChunkEvent
 import press.mantra.compose.nostr.nip30303.tags.ArtifactIdTag
 import press.mantra.compose.repository.MantraRepository
 import press.mantra.compose.text.Markdown
@@ -39,6 +44,109 @@ class DatabaseMantraRepository(
    override suspend fun getChaptersForArtifact(artifactId: String): List<MantraChapter> =
        database.mantraChapterDao().getChaptersByArtifactId(artifactId)

+    override suspend fun addTranslation(
+        artifactId: String,
+        dialectId: String,
+        chatRoomId: String,
+        userPublicKey: HexKey,
+    ): MantraTranslationArtifactVersion? {
+        val artifact = database.mantraArtifactDao().getArtifactById(artifactId) ?: return null
+        val version = database.mantraArtifactVersionDao()
+            .getArtifactVersionsByArtifactId(artifactId)
+            .firstOrNull() ?: return null
+
+        // The translation inherits the source artifact's name/visibility/license.
+        val translationVersionTemplate = TranslationArtifactVersionEvent.build(
+            artifactVersionId = version.id,
+            dialectId = dialectId,
+            name = artifact.name,
+            visibility = artifact.visibility,
+            license = artifact.license,
+        )
+        val translationVersion = MantraTranslationArtifactVersion.fromTranslationArtifactVersionEventTemplate(
+            translationArtifactVersionEventTemplate = translationVersionTemplate,
+            chatRoomId = chatRoomId,
+            userPublicKey = userPublicKey,
+        ) ?: return null
+
+        return try {
+            database.mantraTranslationArtifactVersionDao().upsert(translationVersion)
+            database.marmotInnerEventDao().upsert(
+                MarmotInnerEvent(
+                    id = translationVersion.id,
+                    publicKey = translationVersion.publicKey,
+                    kind = TranslationArtifactVersionEvent.KIND,
+                    createdAt = translationVersion.createdAt,
+                    tags = translationVersionTemplate.tags,
+                    content = translationVersionTemplate.content,
+                    chatRoomId = translationVersion.chatRoomId,
+                )
+            )
+
+            // Mirror the source structure: a translation chapter per chapter and
+            // an (untranslated) translation chunk per chunk.
+            val chapters = database.mantraChapterDao().getChaptersByArtifactVersionId(version.id)
+            chapters.forEach { chapter ->
+                val translationChapterTemplate = TranslationChapterEvent.build(
+                    translationArtifactVersionId = translationVersion.id,
+                    chapterId = chapter.id,
+                    index = chapter.index,
+                )
+                val translationChapter = MantraTranslationChapter.fromTranslationChapterEventTemplate(
+                    translationChapterEventTemplate = translationChapterTemplate,
+                    chatRoomId = chatRoomId,
+                    userPublicKey = userPublicKey,
+                ) ?: return@forEach
+
+                database.mantraTranslationChapterDao().upsert(translationChapter)
+                database.marmotInnerEventDao().upsert(
+                    MarmotInnerEvent(
+                        id = translationChapter.id,
+                        publicKey = translationChapter.publicKey,
+                        kind = TranslationChapterEvent.KIND,
+                        createdAt = translationChapter.createdAt,
+                        tags = translationChapterTemplate.tags,
+                        content = translationChapterTemplate.content,
+                        chatRoomId = translationChapter.chatRoomId,
+                    )
+                )
+
+                val chunks = database.mantraChunkDao().getChunksByChapterId(chapter.id)
+                chunks.forEach { chunk ->
+                    val translationChunkTemplate = TranslationChunkEvent.build(
+                        translationChapterId = translationChapter.id,
+                        chunkId = chunk.id,
+                        index = chunk.index,
+                        text = "", // Untranslated scaffold; filled in during authoring.
+                    )
+                    val translationChunk = MantraTranslationChunk.fromTranslationChunkEventTemplate(
+                        translationChunkEventTemplate = translationChunkTemplate,
+                        chatRoomId = chatRoomId,
+                        userPublicKey = userPublicKey,
+                    ) ?: return@forEach
+
+                    database.mantraTranslationChunkDao().upsert(translationChunk)
+                    database.marmotInnerEventDao().upsert(
+                        MarmotInnerEvent(
+                            id = translationChunk.id,
+                            publicKey = translationChunk.publicKey,
+                            kind = TranslationChunkEvent.KIND,
+                            createdAt = translationChunk.createdAt,
+                            tags = translationChunkTemplate.tags,
+                            content = translationChunkTemplate.content,
+                            chatRoomId = translationChunk.chatRoomId,
+                        )
+                    )
+                }
+            }
+
+            translationVersion
+        } catch (error: Throwable) {
+            logger.e("Failed to add translation for artifact $artifactId", error)
+            null
+        }
+    }
+
    override suspend fun getChapter(id: String): MantraChapter? =
        database.mantraChapterDao().getChapterById(id)

--- a/composeApp/src/commonMain/kotlin/press/mantra/compose/nostr/nip30303/TranslationArtifactVersionEvent.kt
+++ b/composeApp/src/commonMain/kotlin/press/mantra/compose/nostr/nip30303/TranslationArtifactVersionEvent.kt
@@ -39,11 +39,20 @@ class TranslationArtifactVersionEvent(
        const val ALT_DESCRIPTION = "TranslationArtifactVersion"

        fun build(
-            content: String,
+            artifactVersionId: String,
+            dialectId: String,
+            name: String,
+            visibility: String,
+            license: String,
            createdAt: Long = TimeUtils.now(),
-            initializer: TagArrayBuilder<ArtifactEvent>.() -> Unit = {},
-        ) = eventTemplate(KIND, content, createdAt) {
+            initializer: TagArrayBuilder<TranslationArtifactVersionEvent>.() -> Unit = {},
+        ) = eventTemplate(KIND, "", createdAt) {
            alt(ALT_DESCRIPTION)
+            addUnique(ArtifactVersionIdTag.assemble(artifactVersionId))
+            addUnique(DialectIdTag.assemble(dialectId))
+            addUnique(NameTag.assemble(name))
+            addUnique(VisibilityTag.assemble(visibility))
+            addUnique(LicenseTag.assemble(license))
            initializer()
        }
    }
--- a/composeApp/src/commonMain/kotlin/press/mantra/compose/nostr/nip30303/TranslationChapterEvent.kt
+++ b/composeApp/src/commonMain/kotlin/press/mantra/compose/nostr/nip30303/TranslationChapterEvent.kt
@@ -37,11 +37,16 @@ class TranslationChapterEvent(
        const val ALT_DESCRIPTION = "TranslationChapter"

        fun build(
-            content: String,
+            translationArtifactVersionId: String,
+            chapterId: String,
+            index: Int,
            createdAt: Long = TimeUtils.now(),
-            initializer: TagArrayBuilder<ArtifactEvent>.() -> Unit = {},
-        ) = eventTemplate(KIND, content, createdAt) {
+            initializer: TagArrayBuilder<TranslationChapterEvent>.() -> Unit = {},
+        ) = eventTemplate(KIND, "", createdAt) {
            alt(ALT_DESCRIPTION)
+            addUnique(TranslationArtifactVersionIdTag.assemble(translationArtifactVersionId))
+            addUnique(ChapterIdTag.assemble(chapterId))
+            addUnique(IndexTag.assemble(index))
            initializer()
        }
    }
--- a/composeApp/src/commonMain/kotlin/press/mantra/compose/nostr/nip30303/TranslationChunkEvent.kt
+++ b/composeApp/src/commonMain/kotlin/press/mantra/compose/nostr/nip30303/TranslationChunkEvent.kt
@@ -38,11 +38,17 @@ class TranslationChunkEvent(
        const val ALT_DESCRIPTION = "TranslationChunk"

        fun build(
-            content: String,
+            translationChapterId: String,
+            chunkId: String,
+            index: Int,
+            text: String,
            createdAt: Long = TimeUtils.now(),
-            initializer: TagArrayBuilder<ArtifactEvent>.() -> Unit = {},
-        ) = eventTemplate(KIND, content, createdAt) {
+            initializer: TagArrayBuilder<TranslationChunkEvent>.() -> Unit = {},
+        ) = eventTemplate(KIND, text, createdAt) {
            alt(ALT_DESCRIPTION)
+            addUnique(TranslationChapterIdTag.assemble(translationChapterId))
+            addUnique(ChunkIdTag.assemble(chunkId))
+            addUnique(IndexTag.assemble(index))
            initializer()
        }
    }
--- a/composeApp/src/commonMain/kotlin/press/mantra/compose/repository/MantraRepository.kt
+++ b/composeApp/src/commonMain/kotlin/press/mantra/compose/repository/MantraRepository.kt
@@ -24,6 +24,20 @@ interface MantraRepository {

    suspend fun getTranslationsForArtifact(artifactId: String): List<MantraTranslationArtifactVersion>

+    /**
+     * Start a translation of the artifact into the given dialect: creates a
+     * MantraTranslationArtifactVersion for the artifact's latest version, and
+     * scaffolds a MantraTranslationChapter for each existing chapter plus a
+     * MantraTranslationChunk (empty text) for each existing chunk. Returns null
+     * when the artifact has no version to translate.
+     */
+    suspend fun addTranslation(
+        artifactId: String,
+        dialectId: String,
+        chatRoomId: String,
+        userPublicKey: HexKey,
+    ): MantraTranslationArtifactVersion?
+
    /**
     * Add a chapter (markdown [originalText]) to the artifact's latest version.
     * Word/character counts are derived from the text, and the chapter is split
@@ -85,6 +99,13 @@ interface MantraRepository {

            override suspend fun getTranslationsForArtifact(artifactId: String): List<MantraTranslationArtifactVersion> = emptyList()

+            override suspend fun addTranslation(
+                artifactId: String,
+                dialectId: String,
+                chatRoomId: String,
+                userPublicKey: HexKey,
+            ): MantraTranslationArtifactVersion? = null
+
            override suspend fun addChapter(
                artifactId: String,
                name: String,
--- a/composeApp/src/commonMain/kotlin/press/mantra/compose/ui/composable/AddTranslationScreen.kt
+++ b/composeApp/src/commonMain/kotlin/press/mantra/compose/ui/composable/AddTranslationScreen.kt
@@ -0,0 +1,279 @@
+package press.mantra.compose.ui.composable
+
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.ExperimentalLayoutApi
+import androidx.compose.foundation.layout.FlowRow
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.text.input.rememberTextFieldState
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.automirrored.filled.ArrowBack
+import androidx.compose.material.icons.filled.Add
+import androidx.compose.material.icons.filled.Public
+import androidx.compose.material.icons.filled.Title
+import androidx.compose.material.icons.filled.Translate
+import androidx.compose.material3.BottomAppBar
+import androidx.compose.material3.ExperimentalMaterial3Api
+import androidx.compose.material3.ExtendedFloatingActionButton
+import androidx.compose.material3.FilterChip
+import androidx.compose.material3.Icon
+import androidx.compose.material3.IconButton
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.OutlinedTextField
+import androidx.compose.material3.Scaffold
+import androidx.compose.material3.Surface
+import androidx.compose.material3.Text
+import androidx.compose.material3.TopAppBar
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.text.style.TextAlign
+import androidx.compose.ui.tooling.preview.Preview
+import androidx.compose.ui.unit.dp
+import androidx.lifecycle.viewmodel.compose.viewModel
+import com.vitorpamplona.quartz.nip01Core.core.HexKey
+import press.mantra.compose.database.model.MantraArtifact
+import press.mantra.compose.repository.MantraRepository
+import press.mantra.compose.ui.composable.navigation.routes.ArtifactDetailRoute
+import press.mantra.compose.ui.composable.navigation.routes.Route
+import press.mantra.compose.ui.composable.widgets.LoadingDataIndicator
+import press.mantra.compose.ui.theme.TorchTheme
+import press.mantra.compose.ui.view.model.AddTranslationViewModel
+import press.mantra.compose.ui.view.state.AddTranslationUIState
+
+@OptIn(ExperimentalMaterial3Api::class, ExperimentalLayoutApi::class)
+@Composable
+fun AddTranslationScreen(
+    activeUserPublicKey: HexKey,
+    artifactId: String,
+    chatRoomId: String,
+    relayHint: String?,
+    initialAddTranslationUIState: AddTranslationUIState = AddTranslationUIState.Loading,
+    mantraRepository: MantraRepository,
+    onNavigateToRoute: (Route) -> Unit,
+    onNavigateBack: () -> Unit,
+) {
+    val addTranslationViewModel: AddTranslationViewModel = viewModel(
+        factory = AddTranslationViewModel.factory(
+            activeUserPublicKey = activeUserPublicKey,
+            artifactId = artifactId,
+            chatRoomId = chatRoomId,
+            relayHint = relayHint,
+            initialAddTranslationUIState = initialAddTranslationUIState,
+            mantraRepository = mantraRepository,
+        )
+    )
+
+    when (val addTranslationUIState = addTranslationViewModel.addTranslationUIState) {
+        is AddTranslationUIState.Error -> {
+            Column(
+                modifier = Modifier.fillMaxWidth(),
+                horizontalAlignment = Alignment.CenterHorizontally
+            ) {
+                Spacer(modifier = Modifier.height(50.dp))
+                Text(text = addTranslationUIState.message)
+            }
+        }
+
+        is AddTranslationUIState.Loaded -> {
+            val dialectNameFieldState = rememberTextFieldState()
+            val dialectCountryFieldState = rememberTextFieldState()
+            val dialectLanguageFieldState = rememberTextFieldState()
+
+            // null = "New dialect" (show the create fields); otherwise reuse an
+            // existing dialect by id.
+            var selectedDialectId: String? by remember { mutableStateOf(null) }
+
+            Scaffold(
+                topBar = {
+                    TopAppBar(
+                        title = { Text("Translate ${addTranslationUIState.artifact.name}") },
+                        navigationIcon = {
+                            IconButton(onClick = onNavigateBack) {
+                                Icon(
+                                    Icons.AutoMirrored.Filled.ArrowBack,
+                                    contentDescription = "Back"
+                                )
+                            }
+                        },
+                    )
+                },
+                bottomBar = {
+                    BottomAppBar(
+                        actions = {},
+                        floatingActionButton = {
+                            ExtendedFloatingActionButton(
+                                onClick = {
+                                    addTranslationViewModel.addTranslation(
+                                        existingDialectId = selectedDialectId,
+                                        dialectNameField = dialectNameFieldState,
+                                        dialectCountryField = dialectCountryFieldState,
+                                        dialectLanguageField = dialectLanguageFieldState,
+                                        onSuccess = {
+                                            onNavigateToRoute.invoke(
+                                                ArtifactDetailRoute(
+                                                    activeUserPublicKey = activeUserPublicKey,
+                                                    artifactId = artifactId,
+                                                    chatRoomId = chatRoomId,
+                                                    relayHint = relayHint
+                                                )
+                                            )
+                                        },
+                                        onFailure = {}
+                                    )
+                                }
+                            ) {
+                                Icon(
+                                    Icons.Default.Add,
+                                    contentDescription = "Add translation"
+                                )
+                                Text("Add Translation")
+                            }
+                        }
+                    )
+                }
+            ) { innerPadding ->
+                Column(
+                    modifier = Modifier.padding(innerPadding).fillMaxSize().padding(20.dp),
+                    verticalArrangement = Arrangement.spacedBy(10.dp)
+                ) {
+                    Text("Translate into which dialect?")
+
+                    FlowRow(
+                        modifier = Modifier.fillMaxWidth(),
+                        horizontalArrangement = Arrangement.spacedBy(8.dp)
+                    ) {
+                        addTranslationUIState.dialects.forEach { dialect ->
+                            FilterChip(
+                                selected = selectedDialectId == dialect.id,
+                                onClick = { selectedDialectId = dialect.id },
+                                label = { Text(dialect.name) }
+                            )
+                        }
+                        FilterChip(
+                            selected = selectedDialectId == null,
+                            onClick = { selectedDialectId = null },
+                            leadingIcon = {
+                                Icon(
+                                    Icons.Default.Add,
+                                    contentDescription = "Create a new dialect"
+                                )
+                            },
+                            label = { Text("New dialect") }
+                        )
+                    }
+
+                    // Only collect new-dialect details when not reusing an existing one.
+                    if (selectedDialectId == null) {
+                        OutlinedTextField(
+                            modifier = Modifier.fillMaxWidth(),
+                            state = dialectNameFieldState,
+                            leadingIcon = {
+                                Icon(
+                                    Icons.Default.Title,
+                                    contentDescription = "Name of the dialect"
+                                )
+                            },
+                            label = { Text("Dialect Name") },
+                            placeholder = { Text("eg. Sesotho") },
+                        )
+
+                        OutlinedTextField(
+                            modifier = Modifier.fillMaxWidth(),
+                            state = dialectCountryFieldState,
+                            leadingIcon = {
+                                Icon(
+                                    Icons.Default.Public,
+                                    contentDescription = "Country of the dialect"
+                                )
+                            },
+                            label = { Text("Country") },
+                            placeholder = { Text("eg. Lesotho") },
+                        )
+
+                        OutlinedTextField(
+                            modifier = Modifier.fillMaxWidth(),
+                            state = dialectLanguageFieldState,
+                            leadingIcon = {
+                                Icon(
+                                    Icons.Default.Translate,
+                                    contentDescription = "Language of the dialect"
+                                )
+                            },
+                            label = { Text("Language") },
+                            placeholder = { Text("eg. st") },
+                        )
+                    }
+
+                    Text(
+                        text = "The artifact's chapters and chunks will be scaffolded for this translation.",
+                        style = MaterialTheme.typography.labelMedium
+                    )
+                }
+            }
+        }
+
+        AddTranslationUIState.Loading -> {
+            Column(
+                modifier = Modifier.fillMaxWidth().padding(20.dp),
+                horizontalAlignment = Alignment.CenterHorizontally,
+                verticalArrangement = Arrangement.spacedBy(20.dp)
+            ) {
+                Spacer(modifier = Modifier.weight(1f))
+                Text(
+                    text = "Add Translation",
+                    style = MaterialTheme.typography.bodyLarge,
+                    textAlign = TextAlign.Center
+                )
+                LoadingDataIndicator(fillScreen = false)
+                Spacer(modifier = Modifier.weight(2f))
+            }
+        }
+    }
+
+    LaunchedEffect(true) {
+        if (initialAddTranslationUIState == AddTranslationUIState.Loading) {
+            addTranslationViewModel.initiateAddTranslation()
+        }
+    }
+}
+
+@Preview
+@Composable
+private fun AddTranslationScreenPreview() {
+    TorchTheme {
+        Surface(modifier = Modifier.fillMaxSize()) {
+            AddTranslationScreen(
+                activeUserPublicKey = "",
+                artifactId = "artifactId",
+                chatRoomId = "chatRoomId",
+                relayHint = null,
+                initialAddTranslationUIState = AddTranslationUIState.Loaded(
+                    artifact = MantraArtifact(
+                        id = "artifactId",
+                        publicKey = "author",
+                        name = "To Kill a Mockingbird",
+                        url = "https://harper.com/2-kill-Bird",
+                        visibility = "private",
+                        dialectId = "dialectId",
+                        license = "cc",
+                        chatRoomId = "chatRoomId",
+                        signature = ""
+                    )
+                ),
+                mantraRepository = MantraRepository.NO_OP_MANTRA_REPOSITORY,
+                onNavigateToRoute = {},
+                onNavigateBack = {}
+            )
+        }
+    }
+}
--- a/composeApp/src/commonMain/kotlin/press/mantra/compose/ui/composable/ArtifactDetailScreen.kt
+++ b/composeApp/src/commonMain/kotlin/press/mantra/compose/ui/composable/ArtifactDetailScreen.kt
@@ -39,6 +39,7 @@ import com.vitorpamplona.quartz.nip01Core.core.HexKey
 import press.mantra.compose.database.model.MantraArtifact
 import press.mantra.compose.repository.MantraRepository
 import press.mantra.compose.ui.composable.navigation.routes.AddChapterRoute
+import press.mantra.compose.ui.composable.navigation.routes.AddTranslationRoute
 import press.mantra.compose.ui.composable.navigation.routes.ChapterDetailRoute
 import press.mantra.compose.ui.composable.navigation.routes.Route
 import press.mantra.compose.ui.composable.widgets.LoadingDataIndicator
@@ -241,6 +242,29 @@ fun ArtifactDetailScreen(
                            }
                        }
                    }
+
+                    item {
+                        TextButton(
+                            enabled = artifactDetailUIState.versions.isNotEmpty(),
+                            onClick = {
+                                onNavigateToRoute.invoke(
+                                    AddTranslationRoute(
+                                        activeUserPublicKey = activeUserPublicKey,
+                                        artifactId = artifact.id,
+                                        chatRoomId = chatRoomId,
+                                        relayHint = relayHint
+                                    )
+                                )
+                            }
+                        ) {
+                            Icon(
+                                Icons.Default.Translate,
+                                contentDescription = "Add translation"
+                            )
+                            Spacer(modifier = Modifier.width(10.dp))
+                            Text("Add Translation")
+                        }
+                    }
                }
            }
        }
--- a/composeApp/src/commonMain/kotlin/press/mantra/compose/ui/composable/navigation/MantraNavHost.kt
+++ b/composeApp/src/commonMain/kotlin/press/mantra/compose/ui/composable/navigation/MantraNavHost.kt
@@ -90,10 +90,12 @@ import press.mantra.compose.database.repository.DatabaseMantraRepository
 import press.mantra.compose.ui.composable.AddArtifactScreen
 import press.mantra.compose.ui.composable.navigation.routes.AddArtifactRoute
 import press.mantra.compose.ui.composable.navigation.routes.AddChapterRoute
+import press.mantra.compose.ui.composable.navigation.routes.AddTranslationRoute
 import press.mantra.compose.ui.composable.navigation.routes.ArtifactDetailRoute
 import press.mantra.compose.ui.composable.navigation.routes.ChapterDetailRoute
 import press.mantra.compose.ui.composable.ArtifactDetailScreen
 import press.mantra.compose.ui.composable.AddChapterScreen
+import press.mantra.compose.ui.composable.AddTranslationScreen
 import press.mantra.compose.ui.composable.ChapterDetailScreen

@Composable
@@ -714,6 +716,29 @@ fun MantraNavHost(
                }
            )
        }
+        composable<AddTranslationRoute> { backStackEntry ->
+            val route = backStackEntry.toRoute<AddTranslationRoute>()
+
+            AddTranslationScreen(
+                activeUserPublicKey = route.activeUserPublicKey,
+                artifactId = route.artifactId,
+                chatRoomId = route.chatRoomId,
+                relayHint = route.relayHint,
+                mantraRepository = databaseMantraRepository,
+                onNavigateToRoute = { actionRoute ->
+                    // Replace this screen and the stale artifact detail beneath it
+                    // so we land on a freshly-loaded detail showing the new translation.
+                    navController.navigate(route = actionRoute) {
+                        popUpTo<ArtifactDetailRoute> {
+                            inclusive = true
+                        }
+                    }
+                },
+                onNavigateBack = {
+                    navController.popBackStack()
+                }
+            )
+        }
        composable<AddChapterRoute> { backStackEntry ->
            val route = backStackEntry.toRoute<AddChapterRoute>()

--- a/composeApp/src/commonMain/kotlin/press/mantra/compose/ui/composable/navigation/routes/AddTranslationRoute.kt
+++ b/composeApp/src/commonMain/kotlin/press/mantra/compose/ui/composable/navigation/routes/AddTranslationRoute.kt
@@ -0,0 +1,11 @@
+package press.mantra.compose.ui.composable.navigation.routes
+
+import kotlinx.serialization.Serializable
+
+@Serializable
+data class AddTranslationRoute(
+    val activeUserPublicKey: String,
+    val artifactId: String,
+    val chatRoomId: String,
+    val relayHint: String?
+): Route()
--- a/composeApp/src/commonMain/kotlin/press/mantra/compose/ui/view/model/AddTranslationViewModel.kt
+++ b/composeApp/src/commonMain/kotlin/press/mantra/compose/ui/view/model/AddTranslationViewModel.kt
@@ -0,0 +1,137 @@
+package press.mantra.compose.ui.view.model
+
+import androidx.compose.foundation.text.input.TextFieldState
+import androidx.compose.foundation.text.input.clearText
+import androidx.compose.runtime.MutableState
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.setValue
+import androidx.lifecycle.ViewModel
+import androidx.lifecycle.ViewModelProvider
+import androidx.lifecycle.viewModelScope
+import androidx.lifecycle.viewmodel.initializer
+import androidx.lifecycle.viewmodel.viewModelFactory
+import co.touchlab.kermit.Logger
+import com.vitorpamplona.quartz.nip01Core.core.HexKey
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.IO
+import kotlinx.coroutines.launch
+import press.mantra.compose.repository.MantraRepository
+import press.mantra.compose.ui.view.state.AddTranslationUIState
+
+class AddTranslationViewModel(
+    val artifactId: String,
+    val chatRoomId: String,
+    val activeUserPublicKey: HexKey,
+    val relayHint: String?,
+    initialAddTranslationUIState: AddTranslationUIState,
+    val mantraRepository: MantraRepository,
+): ViewModel() {
+
+    var addTranslationUIState: AddTranslationUIState by mutableStateOf(initialAddTranslationUIState)
+        private set
+
+    private val logger = Logger.withTag(TAG)
+
+    val isActionPending: MutableState<Boolean> = mutableStateOf(false)
+
+    fun initiateAddTranslation() {
+        viewModelScope.launch(Dispatchers.IO) {
+            val artifact = mantraRepository.getArtifact(artifactId)
+            addTranslationUIState = if (artifact == null) {
+                AddTranslationUIState.Error("Couldn't find the artifact")
+            } else {
+                AddTranslationUIState.Loaded(
+                    artifact = artifact,
+                    dialects = mantraRepository.getDialects(chatRoomId),
+                )
+            }
+        }
+    }
+
+    fun addTranslation(
+        existingDialectId: HexKey?,
+        dialectNameField: TextFieldState,
+        dialectCountryField: TextFieldState,
+        dialectLanguageField: TextFieldState,
+        onSuccess: () -> Unit,
+        onFailure: () -> Unit
+    ) {
+        val dialectName = dialectNameField.text.toString()
+        val dialectCountry = dialectCountryField.text.toString()
+        val dialectLanguage = dialectLanguageField.text.toString()
+
+        // When no existing dialect is selected, the new-dialect fields are required.
+        val creatingNewDialect = existingDialectId.isNullOrBlank()
+        val newDialectIncomplete = dialectName.isBlank() || dialectCountry.isBlank() || dialectLanguage.isBlank()
+        if (creatingNewDialect && newDialectIncomplete) {
+            onFailure.invoke()
+            return
+        }
+
+        // Guard against double submits from repeated FAB taps.
+        if (isActionPending.value) return
+        isActionPending.value = true
+
+        viewModelScope.launch(Dispatchers.IO) {
+            val translation = runCatching {
+                // Reuse the selected dialect, or create a new one for the translation.
+                val dialectId = if (creatingNewDialect) {
+                    mantraRepository.addDialect(
+                        name = dialectName,
+                        country = dialectCountry,
+                        language = dialectLanguage,
+                        chatRoomId = chatRoomId,
+                        userPublicKey = activeUserPublicKey,
+                    )?.id ?: return@runCatching null
+                } else {
+                    existingDialectId!!
+                }
+
+                mantraRepository.addTranslation(
+                    artifactId = artifactId,
+                    dialectId = dialectId,
+                    chatRoomId = chatRoomId,
+                    userPublicKey = activeUserPublicKey,
+                )
+            }.onFailure { error ->
+                logger.e("Failed to add translation", error)
+            }.getOrNull()
+
+            if (translation != null) {
+                dialectNameField.clearText()
+                dialectCountryField.clearText()
+                dialectLanguageField.clearText()
+                onSuccess.invoke()
+            } else {
+                onFailure.invoke()
+            }
+
+            isActionPending.value = false
+        }
+    }
+
+    companion object {
+        private const val TAG = "AddTranslationViewModel"
+
+        fun factory(
+            activeUserPublicKey: HexKey,
+            artifactId: String,
+            chatRoomId: String,
+            relayHint: String?,
+            initialAddTranslationUIState: AddTranslationUIState = AddTranslationUIState.Loading,
+            mantraRepository: MantraRepository,
+        ): ViewModelProvider.Factory = viewModelFactory {
+            initializer {
+                AddTranslationViewModel(
+                    activeUserPublicKey = activeUserPublicKey,
+                    artifactId = artifactId,
+                    chatRoomId = chatRoomId,
+                    relayHint = relayHint,
+                    initialAddTranslationUIState = initialAddTranslationUIState,
+                    mantraRepository = mantraRepository,
+                )
+            }
+        }
+    }
+}
--- a/composeApp/src/commonMain/kotlin/press/mantra/compose/ui/view/state/AddTranslationUIState.kt
+++ b/composeApp/src/commonMain/kotlin/press/mantra/compose/ui/view/state/AddTranslationUIState.kt
@@ -0,0 +1,17 @@
+package press.mantra.compose.ui.view.state
+
+import press.mantra.compose.database.model.MantraArtifact
+import press.mantra.compose.database.model.MantraDialect
+
+sealed interface AddTranslationUIState {
+    data class Loaded(
+        val artifact: MantraArtifact,
+        val dialects: List<MantraDialect> = emptyList(),
+    ): AddTranslationUIState
+
+    data class Error(
+        val message: String
+    ): AddTranslationUIState
+
+    data object Loading: AddTranslationUIState
+}