Fix crash when pdf cannot be opened.

https://sentry.tools.element.io/organizations/element/issues/1570011/events/efcaaf7382194fd4b7991ca6b05e7532/

Author: bmarty

libraries/mediaviewer/api/src/main/kotlin/io/element/android/libraries/mediaviewer/api/local/pdf/PdfRendererManager.kt

@@ -9,6 +9,9 @@ package io.element.android.libraries.mediaviewer.api.local.pdf
 
 import android.graphics.pdf.PdfRenderer
 import android.os.ParcelFileDescriptor
+import io.element.android.libraries.architecture.AsyncData
+import kotlinx.collections.immutable.ImmutableList
+import kotlinx.collections.immutable.toImmutableList
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.flow.MutableStateFlow
@@ -25,20 +28,28 @@ class PdfRendererManager(
 ) {
     private val mutex = Mutex()
     private var pdfRenderer: PdfRenderer? = null
-    private val mutablePdfPages = MutableStateFlow<List<PdfPage>>(emptyList())
-    val pdfPages: StateFlow<List<PdfPage>> = mutablePdfPages
+    private val mutablePdfPages = MutableStateFlow<AsyncData<ImmutableList<PdfPage>>>(AsyncData.Uninitialized)
+    val pdfPages: StateFlow<AsyncData<ImmutableList<PdfPage>>> = mutablePdfPages
 
     fun open() {
         coroutineScope.launch {
             mutex.withLock {
                 withContext(Dispatchers.IO) {
-                    pdfRenderer = PdfRenderer(parcelFileDescriptor).apply {
-                        // Preload just 3 pages so we can render faster
-                        val firstPages = loadPages(from = 0, to = 3)
-                        mutablePdfPages.value = firstPages
-                        val nextPages = loadPages(from = 3, to = pageCount)
-                        mutablePdfPages.value = firstPages + nextPages
-                    }
+                    runCatching {
+                        PdfRenderer(parcelFileDescriptor)
+                    }.fold(
+                        onSuccess = { pdfRenderer ->
+                            this@PdfRendererManager.pdfRenderer = pdfRenderer
+                            // Preload just 3 pages so we can render faster
+                            val firstPages = pdfRenderer.loadPages(from = 0, to = 3)
+                            mutablePdfPages.value = AsyncData.Success(firstPages.toImmutableList())
+                            val nextPages = pdfRenderer.loadPages(from = 3, to = pdfRenderer.pageCount)
+                            mutablePdfPages.value = AsyncData.Success((firstPages + nextPages).toImmutableList())
+                        },
+                        onFailure = {
+                            mutablePdfPages.value = AsyncData.Failure(it)
+                        }
+                    )
                 }
             }
         }
@@ -47,7 +58,7 @@ class PdfRendererManager(
     fun close() {
         coroutineScope.launch {
             mutex.withLock {
-                mutablePdfPages.value.forEach { pdfPage ->
+                mutablePdfPages.value.dataOrNull()?.forEach { pdfPage ->
                     pdfPage.close()
                 }
                 pdfRenderer?.close()

libraries/mediaviewer/api/src/main/kotlin/io/element/android/libraries/mediaviewer/api/local/pdf/PdfViewer.kt

@@ -28,13 +28,19 @@ import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.graphics.asImageBitmap
 import androidx.compose.ui.layout.ContentScale
 import androidx.compose.ui.res.stringResource
+import androidx.compose.ui.text.style.TextAlign
 import androidx.compose.ui.unit.dp
+import io.element.android.compound.theme.ElementTheme
+import io.element.android.libraries.architecture.AsyncData
+import io.element.android.libraries.designsystem.preview.ElementPreview
+import io.element.android.libraries.designsystem.preview.PreviewsDayNight
 import io.element.android.libraries.designsystem.text.roundToPx
 import io.element.android.libraries.designsystem.text.toDp
+import io.element.android.libraries.designsystem.theme.components.Text
 import io.element.android.libraries.ui.strings.CommonStrings
 import kotlinx.collections.immutable.ImmutableList
-import kotlinx.collections.immutable.toImmutableList
 import me.saket.telephoto.zoomable.zoomable
+import java.io.IOException
 
 @Composable
 fun PdfViewer(
@@ -59,14 +65,56 @@ fun PdfViewer(
         }
         val pdfPages = pdfViewerState.getPages()
         PdfPagesView(
-            pdfPages = pdfPages.toImmutableList(),
+            pdfPages = pdfPages,
             lazyListState = pdfViewerState.lazyListState,
         )
     }
 }
 
 @Composable
 private fun PdfPagesView(
+    pdfPages: AsyncData<ImmutableList<PdfPage>>,
+    lazyListState: LazyListState,
+    modifier: Modifier = Modifier,
+) {
+    when (pdfPages) {
+        is AsyncData.Uninitialized,
+        is AsyncData.Loading -> Unit
+        is AsyncData.Failure -> PdfPagesErrorView(
+            pdfPages.error,
+            modifier,
+        )
+        is AsyncData.Success -> PdfPagesContentView(
+            pdfPages = pdfPages.data,
+            lazyListState = lazyListState,
+            modifier = modifier
+        )
+    }
+}
+
+@Composable
+fun PdfPagesErrorView(
+    error: Throwable,
+    modifier: Modifier = Modifier,
+) {
+    Box(
+        modifier = modifier.fillMaxSize(),
+        contentAlignment = Alignment.Center,
+    ) {
+        Text(
+            text = buildString {
+                append(stringResource(id = CommonStrings.error_unknown))
+                append("\n\n")
+                append(error.localizedMessage)
+            },
+            textAlign = TextAlign.Center,
+            style = ElementTheme.typography.fontBodyLgRegular,
+        )
+    }
+}
+
+@Composable
+private fun PdfPagesContentView(
     pdfPages: ImmutableList<PdfPage>,
     lazyListState: LazyListState,
     modifier: Modifier = Modifier,
@@ -117,3 +165,11 @@ private fun PdfPageView(
         }
     }
 }
+
+@PreviewsDayNight
+@Composable
+internal fun PdfPagesErrorViewPreview() = ElementPreview {
+    PdfPagesErrorView(
+        error = IOException("file not in PDF format or corrupted"),
+    )
+}

libraries/mediaviewer/api/src/main/kotlin/io/element/android/libraries/mediaviewer/api/local/pdf/PdfViewerState.kt

@@ -19,6 +19,8 @@ import androidx.compose.runtime.remember
 import androidx.compose.runtime.rememberCoroutineScope
 import androidx.compose.runtime.setValue
 import androidx.compose.ui.platform.LocalContext
+import io.element.android.libraries.architecture.AsyncData
+import kotlinx.collections.immutable.ImmutableList
 import kotlinx.coroutines.CoroutineScope
 import me.saket.telephoto.zoomable.ZoomableState
 import me.saket.telephoto.zoomable.rememberZoomableState
@@ -35,10 +37,10 @@ class PdfViewerState(
     private var pdfRendererManager by mutableStateOf<PdfRendererManager?>(null)
 
     @Composable
-    fun getPages(): List<PdfPage> {
+    fun getPages(): AsyncData<ImmutableList<PdfPage>> {
         return pdfRendererManager?.run {
             pdfPages.collectAsState().value
-        } ?: emptyList()
+        } ?: AsyncData.Uninitialized
     }
 
     fun openForWidth(maxWidth: Int) {