style(代码风格): 整理代码归属与命名

ofdgo_backend_registry.go

@@ -0,0 +1,71 @@
+// Copyright 2025-2026 肖其顿 (XIAO QI DUN)
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package ofdgo
+
+import (
+	"fmt"
+	"sync"
+)
+
+// backendRegistry 保存后端工厂，不共享有状态的后端实例
+var backendRegistry = struct {
+	sync.RWMutex
+	factories map[string]func() RenderBackends
+}{factories: make(map[string]func() RenderBackends)}
+
+// RegisterRenderBackend 注册后端组合，工厂应返回独立实例，重复标识不会覆盖已有实现
+// 入参: name 后端标识, factory 后端工厂
+// 返回: error 无效或重复注册错误
+func RegisterRenderBackend(name string, factory func() RenderBackends) error {
+	if name == "" || factory == nil {
+		return fmt.Errorf("backend name and factory are required")
+	}
+	backendRegistry.Lock()
+	defer backendRegistry.Unlock()
+	if _, exists := backendRegistry.factories[name]; exists {
+		return fmt.Errorf("render backend %q already registered", name)
+	}
+	backendRegistry.factories[name] = factory
+	return nil
+}
+
+// NewRenderBackends 创建已注册后端组合，各项能力通过Info报告实际提供者
+// 入参: name 已注册后端标识
+// 返回: RenderBackends 后端组合, error 未知后端错误
+func NewRenderBackends(name string) (RenderBackends, error) {
+	backendRegistry.RLock()
+	factory := backendRegistry.factories[name]
+	backendRegistry.RUnlock()
+	if factory == nil {
+		return RenderBackends{}, fmt.Errorf("unknown render backend %q", name)
+	}
+	return factory(), nil
+}
+
+// RenderBackendInfos 列出已注册组合及其实际能力，供原生程序和WASM共用
+// 返回: map[string]BackendInfo 后端能力
+func RenderBackendInfos() map[string]BackendInfo {
+	backendRegistry.RLock()
+	factories := make(map[string]func() RenderBackends, len(backendRegistry.factories))
+	for name, factory := range backendRegistry.factories {
+		factories[name] = factory
+	}
+	backendRegistry.RUnlock()
+	result := make(map[string]BackendInfo, len(factories))
+	for name, factory := range factories {
+		result[name] = factory().Info()
+	}
+	return result
+}