refactor(plugins): restructure admin and message_gateway into standard layered sub-packages

backend/plugins/domain/admin/service/template.go

@@ -0,0 +1,86 @@
+// Copyright 2026 Arctel.net
+// SPDX-License-Identifier: Apache-2.0
+
+package service
+
+import (
+	"Wavelet/plugins/domain/admin/errs"
+	"Wavelet/plugins/domain/admin/model"
+	"Wavelet/plugins/domain/admin/repository"
+	"context"
+)
+
+// CreateTemplate persists a new notification template after key collision and field checks.
+func CreateTemplate(ctx context.Context, req model.CreateTemplateRequest) (model.Template, error) {
+	exists, err := repository.TemplateExistsByKey(ctx, req.Key)
+	if err != nil {
+		return model.Template{}, err
+	}
+	if exists {
+		return model.Template{}, errs.ErrTemplateKeyExists
+	}
+
+	tmpl := model.Template{
+		Key:         req.Key,
+		Name:        req.Name,
+		Type:        req.Type,
+		Subject:     req.Subject,
+		Content:     req.Content,
+		Description: req.Description,
+		IsSystem:    false,
+	}
+	if err := tmpl.Validate(); err != nil {
+		return model.Template{}, err
+	}
+	if err := repository.CreateTemplateRecord(ctx, &tmpl); err != nil {
+		return model.Template{}, err
+	}
+	return tmpl, nil
+}
+
+// ListTemplates returns every notification template.
+func ListTemplates(ctx context.Context) ([]model.Template, error) {
+	return repository.ListTemplatesRecord(ctx)
+}
+
+// GetTemplate loads a template by its identifier.
+func GetTemplate(ctx context.Context, key string) (model.Template, error) {
+	tmpl, err := repository.GetTemplateByKey(ctx, key)
+	if err != nil {
+		return model.Template{}, translateNotFound(err, errs.ErrTemplateNotFound)
+	}
+	return tmpl, nil
+}
+
+// UpdateTemplate rewrites the mutable fields of an existing template.
+func UpdateTemplate(ctx context.Context, key string, req model.UpdateTemplateRequest) (model.Template, error) {
+	tmpl, err := GetTemplate(ctx, key)
+	if err != nil {
+		return model.Template{}, err
+	}
+
+	tmpl.Name = req.Name
+	tmpl.Type = req.Type
+	tmpl.Subject = req.Subject
+	tmpl.Content = req.Content
+	tmpl.Description = req.Description
+	if err := tmpl.Validate(); err != nil {
+		return model.Template{}, err
+	}
+	if err := repository.SaveTemplateRecord(ctx, &tmpl); err != nil {
+		return model.Template{}, err
+	}
+	return tmpl, nil
+}
+
+// DeleteTemplate removes a custom template; system presets are protected.
+func DeleteTemplate(ctx context.Context, key string) error {
+	tmpl, err := GetTemplate(ctx, key)
+	if err != nil {
+		return err
+	}
+	if tmpl.IsSystem {
+		return errs.ErrSystemTemplateCannotDelete
+	}
+	return repository.DeleteTemplateRecord(ctx, &tmpl)
+}