Convert settings migration logic to kotlin

Author: Yevhen Babiichuk (DustDFG)

app/src/main/java/org/schabi/newpipe/settings/migration/MigrationManager.java

@@ -0,0 +1,98 @@
+/*
+ * SPDX-FileCopyrightText: 2020-2026 NewPipe contributors <https://newpipe.net>
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+package org.schabi.newpipe.settings.migration
+
+import android.content.Context
+import androidx.appcompat.app.AlertDialog
+import org.schabi.newpipe.R
+import org.schabi.newpipe.error.ErrorUtil.Companion.showUiErrorSnackbar
+
+/**
+ * MigrationManager is responsible for running migrations and showing the user information about
+ * the migrations that were applied.
+ */
+object MigrationManager {
+    private val TAG: String = MigrationManager::class.java.getSimpleName()
+
+    /**
+     * List of UI actions that are performed after the UI is initialized (e.g. showing alert
+     * dialogs) to inform the user about changes that were applied by migrations.
+     */
+    private val MIGRATION_INFO: MutableList<(Context) -> Unit> = ArrayList()
+
+    /**
+     * Run all migrations that are needed for the current version of NewPipe.
+     * This method should be called at the start of the application, before any other operations
+     * that depend on the settings.
+     *
+     * @param context Context that can be used to run migrations
+     */
+    @JvmStatic
+    fun runMigrationsIfNeeded(context: Context) {
+        SettingMigrations.runMigrationsIfNeeded(context)
+    }
+
+    /**
+     * Perform UI actions informing about migrations that took place if they are present.
+     * @param context Context that can be used to show dialogs/snackbars/toasts
+     */
+    @JvmStatic
+    fun showUserInfoIfPresent(context: Context) {
+        if (MIGRATION_INFO.isEmpty()) {
+            return
+        }
+
+        try {
+            MIGRATION_INFO[0](context)
+        } catch (e: Exception) {
+            showUiErrorSnackbar(context, "Showing migration info to the user", e)
+            // Remove the migration that caused the error and continue with the next one
+            MIGRATION_INFO.removeAt(0)
+            showUserInfoIfPresent(context)
+        }
+    }
+
+    /**
+     * Add a migration info action that will be executed after the UI is initialized.
+     * This can be used to show dialogs/snackbars/toasts to inform the user about changes that
+     * were applied by migrations.
+     *
+     * @param info the action to be executed
+     */
+    @JvmStatic
+    fun addMigrationInfo(info: (Context) -> Unit) {
+        MIGRATION_INFO.add(info)
+    }
+
+    /**
+     * This method should be called when the user dismisses the migration info
+     * to check if there are any more migration info actions to be shown.
+     * @param context Context that can be used to show dialogs/snackbars/toasts
+     */
+    @JvmStatic
+    fun onMigrationInfoDismissed(context: Context) {
+        MIGRATION_INFO.removeAt(0)
+        showUserInfoIfPresent(context)
+    }
+
+    /**
+     * Creates a dialog to inform the user about the migration.
+     * @param uiContext Context that can be used to show dialogs/snackbars/toasts
+     * @param title the title of the dialog
+     * @param message the message of the dialog
+     * @return the dialog that can be shown to the user with a custom dismiss listener
+     */
+    @JvmStatic
+    fun createMigrationInfoDialog(uiContext: Context, title: String, message: String): AlertDialog {
+        return AlertDialog.Builder(uiContext)
+            .setTitle(title)
+            .setMessage(message)
+            .setPositiveButton(R.string.ok, null)
+            .setOnDismissListener { onMigrationInfoDismissed(uiContext) }
+            .setCancelable(false) // prevents the dialog from being dismissed accidentally
+            .create()
+    }
+}