feat(后端架构): 完善后端解耦

ofdgo_render.go

@@ -0,0 +1,115 @@
+// 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
+
+// RenderPage 编译页面为与绘图库无关的只读绘制数据
+// 入参: page 页面内容
+// 返回: *RasterPage 绘制页面, error 错误信息
+func (r *Renderer) RenderPage(page *PageContent) (*RasterPage, error) {
+	return r.CompilePage(page)
+}
+
+// GetPageBox 获取页面物理区域
+// 入参: page 页面内容
+// 返回: Box 区域, error 错误信息
+func (r *Renderer) GetPageBox(page *PageContent) (Box, error) {
+	area, err := r.Reader.resolvePageArea(page.Area, page.Template)
+	if err != nil {
+		return Box{}, err
+	}
+	boxStr := area.PhysicalBox
+	if boxStr == "" {
+		boxStr = area.ApplicationBox
+	}
+	if boxStr == "" {
+		boxStr = area.ContentBox
+	}
+	if boxStr == "" {
+		boxStr = "0 0 210 297"
+	}
+	return ParseBox(boxStr)
+}
+
+// PageLinks 获取页面、模板和可见注释的点击链接，包含复杂区域、组合图元和附件动作
+// 入参: page 页面内容
+// 返回: []PageLink 页面链接, error 错误信息
+func (r *Renderer) PageLinks(page *PageContent) ([]PageLink, error) {
+	box, err := r.GetPageBox(page)
+	if err != nil {
+		return nil, err
+	}
+	sources := r.pageActionSources(page, box)
+	if r.RenderAnnotations {
+		sources = append(sources, r.annotationActionSources(r.Reader.Annots[page.ID])...)
+	}
+	var links []PageLink
+	var bookmarks map[string]Dest
+	for sourceIndex, source := range sources {
+		start := len(links)
+		for _, action := range source.Actions {
+			if action.Event != "CLICK" {
+				continue
+			}
+			box, path, err := r.actionLinkRegion(source, action)
+			if err != nil {
+				return nil, err
+			}
+			if box.W <= 0 || box.H <= 0 {
+				continue
+			}
+			link := PageLink{Box: box, Path: path}
+			if action.Goto != nil {
+				if bookmarks == nil {
+					doc, err := r.Reader.Doc()
+					if err != nil {
+						return nil, err
+					}
+					bookmarks = make(map[string]Dest, len(doc.Bookmarks.Bookmark))
+					for _, bookmark := range doc.Bookmarks.Bookmark {
+						bookmarks[bookmark.Name] = bookmark.Dest
+					}
+				}
+				if dest := gotoDest(action.Goto, bookmarks); dest != nil {
+					value := *dest
+					link.Dest = &value
+					links = append(links, link)
+				}
+			} else if action.URI != nil && action.URI.URI != "" {
+				link.URI = resolveActionURI(*action.URI)
+				links = append(links, link)
+			} else if action.GotoA != nil {
+				link.Attachment = action.GotoA.AttachID
+				links = append(links, link)
+			}
+		}
+		if len(links)-start > 1 {
+			for i := start; i < len(links); i++ {
+				links[i].Group = sourceIndex + 1
+			}
+		}
+	}
+	return links, nil
+}
+
+// RenderPageByIndex 按索引渲染页面
+// 入参: index 页面索引，从0开始
+// 返回: *RasterPage 绘制页面, error 错误信息
+func (r *Renderer) RenderPageByIndex(index int) (*RasterPage, error) {
+	page, err := r.Reader.PageContentByIndex(index)
+	if err != nil {
+		return nil, err
+	}
+	return r.RenderPage(page)
+}