feat: add audio and PDF file upload support to ShortNotePostScreen

Add a new "attach file" button that opens a document picker filtered to
audio/* and application/pdf MIME types. This uses OpenMultipleDocuments
contract since PickVisualMedia only supports images/videos.

- Add SelectFromFiles composable with AttachFile icon button
- Add isAudio() and isDocument() helpers to SelectedMedia
- Add FilePreviewPlaceholder for audio/PDF thumbnail display
- Add upload_file string resource

https://claude.ai/code/session_018naEzfHjLRQLgaWAtY4aSz

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/actions/uploads/SelectFromFiles.kt

@@ -0,0 +1,129 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.ui.actions.uploads
+
+import android.net.Uri
+import androidx.activity.compose.rememberLauncherForActivityResult
+import androidx.activity.result.contract.ActivityResultContracts
+import androidx.compose.foundation.layout.height
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.AttachFile
+import androidx.compose.material3.Icon
+import androidx.compose.material3.IconButton
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.SideEffect
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.platform.LocalContext
+import androidx.compose.ui.unit.dp
+import com.vitorpamplona.amethyst.R
+import com.vitorpamplona.amethyst.ui.components.LoadingAnimation
+import com.vitorpamplona.amethyst.ui.stringRes
+import kotlinx.collections.immutable.ImmutableList
+import kotlinx.collections.immutable.toImmutableList
+import java.util.concurrent.atomic.AtomicBoolean
+
+@Composable
+fun SelectFromFiles(
+    isUploading: Boolean,
+    tint: Color,
+    modifier: Modifier,
+    onFilesChosen: (ImmutableList<SelectedMedia>) -> Unit,
+) {
+    var showFileSelect by remember { mutableStateOf(false) }
+    if (showFileSelect) {
+        FileSelect(
+            onFilesSelected = { files ->
+                showFileSelect = false
+                if (files.isNotEmpty()) {
+                    onFilesChosen(files)
+                }
+            },
+        )
+    }
+
+    FileSelectButton(isUploading, tint, modifier) { showFileSelect = true }
+}
+
+@Composable
+private fun FileSelectButton(
+    isUploading: Boolean,
+    tint: Color,
+    modifier: Modifier,
+    onClick: () -> Unit,
+) {
+    IconButton(
+        modifier = modifier,
+        enabled = !isUploading,
+        onClick = { onClick() },
+    ) {
+        if (!isUploading) {
+            Icon(
+                imageVector = Icons.Default.AttachFile,
+                contentDescription = stringRes(id = R.string.upload_file),
+                modifier = Modifier.height(25.dp),
+                tint = tint,
+            )
+        } else {
+            LoadingAnimation()
+        }
+    }
+}
+
+@Composable
+fun FileSelect(onFilesSelected: (ImmutableList<SelectedMedia>) -> Unit = {}) {
+    val hasLaunched by remember { mutableStateOf(AtomicBoolean(false)) }
+    val resolver = LocalContext.current.contentResolver
+
+    val launcher =
+        rememberLauncherForActivityResult(
+            contract = ActivityResultContracts.OpenMultipleDocuments(),
+            onResult = { uris: List<Uri> ->
+                onFilesSelected(
+                    uris
+                        .map {
+                            SelectedMedia(it, resolver.getType(it))
+                        }.toImmutableList(),
+                )
+                hasLaunched.set(false)
+            },
+        )
+
+    @Composable
+    fun LaunchFilePicker() {
+        SideEffect {
+            if (!hasLaunched.getAndSet(true)) {
+                launcher.launch(
+                    arrayOf(
+                        "audio/*",
+                        "application/pdf",
+                    ),
+                )
+            }
+        }
+    }
+
+    LaunchFilePicker()
+}

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/actions/uploads/SelectFromGallery.kt

@@ -55,6 +55,10 @@ class SelectedMedia(
     fun isImage() = mimeType?.startsWith("image")
 
     fun isVideo() = mimeType?.startsWith("video")
+
+    fun isAudio() = mimeType?.startsWith("audio")
+
+    fun isDocument() = mimeType == "application/pdf"
 }
 
 @Composable

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/actions/uploads/ShowImageUploadItem.kt

@@ -28,14 +28,21 @@ import android.os.Build
 import androidx.compose.animation.core.animateFloatAsState
 import androidx.compose.foundation.Image
 import androidx.compose.foundation.background
+import androidx.compose.foundation.layout.Arrangement
 import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.WindowInsets
 import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.layout.size
 import androidx.compose.foundation.layout.windowInsetsPadding
 import androidx.compose.foundation.shape.CircleShape
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.AudioFile
+import androidx.compose.material.icons.filled.PictureAsPdf
 import androidx.compose.material3.CircularProgressIndicator
+import androidx.compose.material3.Icon
 import androidx.compose.material3.IconButton
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.ProgressIndicatorDefaults
@@ -117,6 +124,16 @@ fun ShowImageGallery(
                     .fillMaxWidth()
                     .windowInsetsPadding(WindowInsets(0.dp, 0.dp, 0.dp, 0.dp)),
         )
+    } else if (media.isAudio() == true) {
+        FilePreviewPlaceholder(
+            icon = Icons.Default.AudioFile,
+            label = media.mimeType ?: "audio/*",
+        )
+    } else if (media.isDocument() == true) {
+        FilePreviewPlaceholder(
+            icon = Icons.Default.PictureAsPdf,
+            label = media.mimeType ?: "application/pdf",
+        )
     } else if (media.isVideo() == true && Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {
         var bitmap by remember { mutableStateOf<Bitmap?>(null) }
         val context = LocalContext.current
@@ -254,3 +271,36 @@ fun UploadingState(
         )
     }
 }
+
+@Composable
+fun FilePreviewPlaceholder(
+    icon: androidx.compose.ui.graphics.vector.ImageVector,
+    label: String,
+) {
+    Box(
+        modifier =
+            Modifier
+                .fillMaxWidth()
+                .background(MaterialTheme.colorScheme.surfaceVariant),
+        contentAlignment = Alignment.Center,
+    ) {
+        Column(
+            horizontalAlignment = Alignment.CenterHorizontally,
+            verticalArrangement = Arrangement.Center,
+            modifier = Modifier.padding(8.dp),
+        ) {
+            Icon(
+                imageVector = icon,
+                contentDescription = label,
+                modifier = Modifier.size(40.dp),
+                tint = MaterialTheme.colorScheme.onSurfaceVariant,
+            )
+            Text(
+                text = label,
+                color = MaterialTheme.colorScheme.onSurfaceVariant,
+                fontSize = 10.sp,
+                textAlign = TextAlign.Center,
+            )
+        }
+    }
+}

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/screen/loggedIn/home/ShortNotePostScreen.kt

@@ -63,6 +63,7 @@ import com.vitorpamplona.amethyst.model.Note
 import com.vitorpamplona.amethyst.ui.actions.mediaServers.FileServerSelectionRow
 import com.vitorpamplona.amethyst.ui.actions.uploads.MAX_VOICE_RECORD_SECONDS
 import com.vitorpamplona.amethyst.ui.actions.uploads.RecordVoiceButton
+import com.vitorpamplona.amethyst.ui.actions.uploads.SelectFromFiles
 import com.vitorpamplona.amethyst.ui.actions.uploads.SelectFromGallery
 import com.vitorpamplona.amethyst.ui.actions.uploads.SelectedMedia
 import com.vitorpamplona.amethyst.ui.actions.uploads.TakePictureButton
@@ -504,6 +505,14 @@ private fun BottomRowActions(postViewModel: ShortNotePostViewModel) {
             maxDurationSeconds = MAX_VOICE_RECORD_SECONDS,
         )
 
+        SelectFromFiles(
+            isUploading = postViewModel.isUploadingImage,
+            tint = MaterialTheme.colorScheme.onBackground,
+            modifier = Modifier,
+        ) {
+            postViewModel.selectImage(it)
+        }
+
         if (postViewModel.canUsePoll) {
             // These should be hashtag recommendations the user selects in the future.
             // val hashtag = stringRes(R.string.poll_hashtag)

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

@@ -170,6 +170,7 @@
     <string name="video_saved_to_the_gallery">Video saved to the phone\'s video gallery</string>
     <string name="failed_to_save_the_video">Failed to save the video</string>
     <string name="upload_image">Upload Image</string>
+    <string name="upload_file">Upload File</string>
     <string name="take_a_picture">Take a picture</string>
     <string name="record_a_video">Record a video</string>
     <string name="record_a_message">Record a message</string>