Add device-specific support configs.

app/src/main/java/org/thoughtcrime/securesms/notifications/DelayedNotificationConfig.kt

@@ -0,0 +1,62 @@
+package org.thoughtcrime.securesms.notifications
+
+import android.os.Build
+import androidx.annotation.VisibleForTesting
+import com.fasterxml.jackson.annotation.JsonProperty
+import org.signal.core.util.logging.Log
+import org.thoughtcrime.securesms.util.JsonUtils
+import org.thoughtcrime.securesms.util.RemoteConfig
+import java.io.IOException
+
+/**
+ * Remote configs for a device to show a support screen in an effort to prevent delayed notifications
+ */
+object DelayedNotificationConfig {
+
+  private val TAG = Log.tag(DelayedNotificationConfig::class.java)
+  private const val GENERAL_SUPPORT_URL = "https://support.signal.org/hc/articles/360007318711#android_notifications_troubleshooting"
+
+  val currentConfig: Config by lazy { computeConfig() }
+
+  /**
+   * Maps a device model to specific modifications set in order to support better notification
+   * @param model either exact device model name or model name that ends with a wildcard
+   * @param showPreemptively shows support sheet immediately if true or after a vitals failure if not, still dependent on localePercent
+   * @param link represents the Signal support url that corresponds to this device model
+   * @param localePercent represents the percent of people who will get this change per country
+   */
+  data class Config(
+    @JsonProperty val model: String = "",
+    @JsonProperty val showPreemptively: Boolean = false,
+    @JsonProperty val link: String = GENERAL_SUPPORT_URL,
+    @JsonProperty val localePercent: String = RemoteConfig.promptBatterySaver
+  )
+
+  @VisibleForTesting
+  fun computeConfig(): Config {
+    val default = Config()
+    val serialized = RemoteConfig.promptDelayedNotificationConfig
+    if (serialized.isNullOrBlank()) {
+      return default
+    }
+
+    val list: List<Config> = try {
+      JsonUtils.fromJsonArray(serialized, Config::class.java)
+    } catch (e: IOException) {
+      Log.w(TAG, "Failed to parse json!", e)
+      emptyList()
+    }
+
+    val config: Config? = list
+      .filter { it.model.isNotEmpty() }
+      .find {
+        if (it.model.last() == '*') {
+          Build.MODEL.startsWith(it.model.substring(0, it.model.length - 1))
+        } else {
+          it.model.contains(Build.MODEL)
+        }
+      }
+
+    return config ?: default
+  }
+}

app/src/main/java/org/thoughtcrime/securesms/notifications/SlowNotificationHeuristics.kt

@@ -143,6 +143,10 @@ object SlowNotificationHeuristics {
     return true
   }
 
+  fun showPreemptively(): Boolean {
+    return DelayedNotificationConfig.currentConfig.showPreemptively
+  }
+
   private fun hasRepeatedFailedServiceStarts(metrics: List<LocalMetricsDatabase.EventMetrics>, minimumEventAgeMs: Long, minimumEventCount: Int, failurePercentage: Float): Boolean {
     if (!haveEnoughData(SignalLocalMetrics.FcmServiceStartSuccess.NAME, minimumEventAgeMs) && !haveEnoughData(SignalLocalMetrics.FcmServiceStartFailure.NAME, minimumEventAgeMs)) {
       Log.d(TAG, "insufficient data for service starts")

app/src/main/java/org/thoughtcrime/securesms/notifications/VitalsViewModel.kt

@@ -46,7 +46,7 @@ class VitalsViewModel(private val context: Application) : AndroidViewModel(conte
   private fun checkHeuristics(): Single<State> {
     return Single.fromCallable {
       var state = State.NONE
-      if (SlowNotificationHeuristics.isHavingDelayedNotifications()) {
+      if (SlowNotificationHeuristics.showPreemptively() || SlowNotificationHeuristics.isHavingDelayedNotifications()) {
         if (SlowNotificationHeuristics.isPotentiallyCausedByBatteryOptimizations() && SlowNotificationHeuristics.shouldPromptBatterySaver()) {
           state = State.PROMPT_BATTERY_SAVER_DIALOG
         } else if (SlowNotificationHeuristics.shouldPromptUserForLogs()) {