add message template

app/Models/MessageTemplate.php

@@ -0,0 +1,48 @@
+<?php
+
+namespace App\Models;
+
+use App\Enums\MessageTemplateNameEnum;
+use Illuminate\Database\Eloquent\Relations\BelongsTo;
+
+class MessageTemplate extends NexusModel
+{
+    protected $fillable = ['name', 'content', 'language_id'];
+
+    public $timestamps = true;
+
+    protected $casts = [
+        'name' => MessageTemplateNameEnum::class,
+    ];
+
+    public static function listAllNames(): array
+    {
+        $result = [];
+        foreach (MessageTemplateNameEnum::cases() as $messageTemplate) {
+            $result[$messageTemplate->value] = $messageTemplate->label();
+        }
+        return $result;
+    }
+
+    public function language(): BelongsTo
+    {
+        return $this->belongsTo(Language::class);
+    }
+
+    public static function forRegisterWelcome($languageId, array $placeholders): null|string
+    {
+        $result = self::query()->where("language_id", $languageId)
+            ->where('name', MessageTemplateNameEnum::REGISTER_WELCOME->value)
+            ->first();
+        return self::format($result, $placeholders);
+    }
+
+    private static function format(self|null $template, array $placeholders): null|string
+    {
+        if ($template && $template->content) {
+            $search = array_map(function ($value) {return ":$value";}, array_keys($placeholders));
+            return str_replace($search, array_values($placeholders), $template->content);
+        }
+        return null;
+    }
+}