Pages: Updated editor field to always be set

- Migration for setting on existing pages
- Added test to cover simple new page scenario

For #5117

database/migrations/2024_09_29_140340_ensure_editor_value_set.php

@@ -0,0 +1,48 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Support\Facades\DB;
+
+return new class extends Migration
+{
+    /**
+     * Run the migrations.
+     */
+    public function up(): void
+    {
+        // Ensure we have an "editor" value set for pages
+
+        // Get default
+        $default = DB::table('settings')
+            ->where('setting_key', '=', 'app-editor')
+            ->first()
+            ->value ?? 'wysiwyg';
+        $default = ($default === 'markdown') ? 'markdown' : 'wysiwyg';
+
+        // We set it to 'markdown' for pages currently with markdown content
+        DB::table('pages')
+            ->where('editor', '=', '')
+            ->where('markdown', '!=', '')
+            ->update(['editor' => 'markdown']);
+
+        // We set it to 'wysiwyg' where we have HTML but no markdown
+        DB::table('pages')
+            ->where('editor', '=', '')
+            ->where('markdown', '=', '')
+            ->where('html', '!=', '')
+            ->update(['editor' => 'wysiwyg']);
+
+        // Otherwise, where still empty, set to the current default
+        DB::table('pages')
+            ->where('editor', '=', '')
+            ->update(['editor' => $default]);
+    }
+
+    /**
+     * Reverse the migrations.
+     */
+    public function down(): void
+    {
+        // Can't reverse due to not knowing what would have been empty before
+    }
+};