fix loading posts with invalid published_at in preview card (#4993)

closes #4992

app/src/main/java/com/keylesspalace/tusky/di/NetworkModule.kt

@@ -82,8 +82,8 @@ object NetworkModule {
     @Provides
     @Singleton
     fun providesMoshi(): Moshi = Moshi.Builder()
-        .add(Date::class.java, Rfc3339DateJsonAdapter())
         .add(GuardedAdapter.ANNOTATION_FACTORY)
+        .add(Date::class.java, Rfc3339DateJsonAdapter())
         // Enum types with fallback value
         .add(
             Attachment.Type::class.java,

app/src/main/java/com/keylesspalace/tusky/entity/PreviewCard.kt

@@ -15,6 +15,7 @@
 
 package com.keylesspalace.tusky.entity
 
+import com.keylesspalace.tusky.json.Guarded
 import com.squareup.moshi.Json
 import com.squareup.moshi.JsonClass
 import java.util.Date
@@ -27,7 +28,8 @@ data class PreviewCard(
     val authors: List<PreviewCardAuthor> = emptyList(),
     @Json(name = "author_name") val authorName: String? = null,
     @Json(name = "provider_name") val providerName: String? = null,
-    @Json(name = "published_at") val publishedAt: Date?,
+    // sometimes this date is invalid https://github.com/tuskyapp/Tusky/issues/4992
+    @Json(name = "published_at") @Guarded val publishedAt: Date?,
     val image: String? = null,
     val type: String,
     val width: Int = 0,

app/src/main/java/com/keylesspalace/tusky/json/GuardedAdapter.kt

@@ -17,8 +17,8 @@
 
 package com.keylesspalace.tusky.json
 
+import android.util.Log
 import com.squareup.moshi.JsonAdapter
-import com.squareup.moshi.JsonDataException
 import com.squareup.moshi.JsonReader
 import com.squareup.moshi.JsonWriter
 import com.squareup.moshi.Moshi
@@ -35,10 +35,12 @@ class GuardedAdapter<T> private constructor(
 
     override fun fromJson(reader: JsonReader): T? {
         return try {
-            delegate.fromJson(reader)
-        } catch (e: JsonDataException) {
-            reader.skipValue()
+            reader.peekJson().use { delegate.fromJson(it) }
+        } catch (e: Exception) {
+            Log.w("GuardedAdapter", "failed to read json", e)
             null
+        } finally {
+            reader.skipValue()
         }
     }