feat(图形界面): 将OFDGo编译为WASM提供WebUI

internal/webui/webui.go

@@ -0,0 +1,182 @@
+// 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 webui
+
+import (
+	"bytes"
+	"fmt"
+
+	"github.com/xiaoqidun/ofdgo"
+)
+
+// OpenOptions 打开OFD文档选项
+type OpenOptions struct {
+	Fonts []FontFile
+}
+
+// FontFile 字体文件
+type FontFile = ofdgo.FontFile
+
+// FontInfo OFD字体信息
+type FontInfo = ofdgo.FontInfo
+
+// Session WebUI文档会话
+type Session struct {
+	Reader   *ofdgo.Reader
+	Renderer *ofdgo.Renderer
+	doc      *ofdgo.Document
+}
+
+// DocumentInfo 文档信息
+type DocumentInfo struct {
+	Version      string     `json:"version"`
+	DocType      string     `json:"docType"`
+	Title        string     `json:"title"`
+	Author       string     `json:"author"`
+	Subject      string     `json:"subject"`
+	CreationDate string     `json:"creationDate"`
+	ModDate      string     `json:"modDate"`
+	PageCount    int        `json:"pageCount"`
+	FontCount    int        `json:"fontCount"`
+	Fonts        []FontInfo `json:"fonts"`
+	Pages        []PageInfo `json:"pages"`
+}
+
+// PageInfo 页面信息
+type PageInfo struct {
+	Index  int     `json:"index"`
+	ID     string  `json:"id"`
+	Width  float64 `json:"width"`
+	Height float64 `json:"height"`
+}
+
+// PageSVG 页面SVG结果
+type PageSVG struct {
+	Index  int     `json:"index"`
+	Number int     `json:"number"`
+	ID     string  `json:"id"`
+	Width  float64 `json:"width"`
+	Height float64 `json:"height"`
+	SVG    string  `json:"svg"`
+}
+
+// Open 打开浏览器内存中的OFD文档
+// 入参: data OFD文件数据, opts 打开选项
+// 返回: *Session 文档会话, error 错误信息
+func Open(data []byte, opts OpenOptions) (*Session, error) {
+	if len(data) == 0 {
+		return nil, fmt.Errorf("empty ofd data")
+	}
+	reader, err := ofdgo.NewReader(bytes.NewReader(data), int64(len(data)))
+	if err != nil {
+		return nil, err
+	}
+	doc, err := reader.Doc()
+	if err != nil {
+		reader.Close()
+		return nil, err
+	}
+	var rendererOptions []ofdgo.RendererOption
+	if len(opts.Fonts) > 0 {
+		fontFS := ofdgo.NewFontFS(opts.Fonts)
+		if fontFS.Len() == 0 {
+			reader.Close()
+			return nil, fmt.Errorf("invalid font file")
+		}
+		rendererOptions = append(rendererOptions, ofdgo.WithFontFS(fontFS))
+	}
+	return &Session{Reader: reader, Renderer: ofdgo.NewRenderer(reader, rendererOptions...), doc: doc}, nil
+}
+
+// Close 关闭文档会话
+// 返回: error 错误信息
+func (s *Session) Close() error {
+	if s == nil || s.Reader == nil {
+		return nil
+	}
+	return s.Reader.Close()
+}
+
+// Info 获取文档信息
+// 返回: DocumentInfo 文档信息
+func (s *Session) Info() DocumentInfo {
+	info := DocumentInfo{
+		Version:   s.Reader.Version(),
+		DocType:   s.Reader.DocType(),
+		PageCount: len(s.doc.Pages.Page),
+		Pages:     make([]PageInfo, 0, len(s.doc.Pages.Page)),
+	}
+	if fonts, err := s.Renderer.FontInfos(); err == nil {
+		info.Fonts = fonts
+	}
+	info.FontCount = len(info.Fonts)
+	if docInfo, err := s.Reader.DocInfo(); err == nil && docInfo != nil {
+		info.Title = docInfo.Title
+		info.Author = docInfo.Author
+		info.Subject = docInfo.Subject
+		info.CreationDate = docInfo.CreationDate
+		info.ModDate = docInfo.ModDate
+	}
+	for index, pageRef := range s.doc.Pages.Page {
+		pageInfo := PageInfo{Index: index, ID: pageRef.ID}
+		if page, err := s.Reader.PageContent(pageRef); err == nil {
+			if box, err := s.Renderer.GetPageBox(page); err == nil {
+				pageInfo.Width = box.W
+				pageInfo.Height = box.H
+			}
+		}
+		info.Pages = append(info.Pages, pageInfo)
+	}
+	return info
+}
+
+// RenderPageSVG 渲染页面为SVG
+// 入参: index 页面索引
+// 返回: PageSVG 页面SVG结果, error 错误信息
+func (s *Session) RenderPageSVG(index int) (PageSVG, error) {
+	if s == nil || s.Reader == nil || s.Renderer == nil || s.doc == nil {
+		return PageSVG{}, fmt.Errorf("ofd document is not opened")
+	}
+	if index < 0 || index >= len(s.doc.Pages.Page) {
+		return PageSVG{}, fmt.Errorf("page index %d out of range", index)
+	}
+	pageRef := s.doc.Pages.Page[index]
+	page, err := s.Reader.PageContent(pageRef)
+	if err != nil {
+		return PageSVG{}, err
+	}
+	box, err := s.Renderer.GetPageBox(page)
+	if err != nil {
+		return PageSVG{}, err
+	}
+	var buf bytes.Buffer
+	if err := s.Renderer.RenderToSVG(page, &buf); err != nil {
+		return PageSVG{}, err
+	}
+	return PageSVG{Index: index, Number: index + 1, ID: pageRef.ID, Width: box.W, Height: box.H, SVG: buf.String()}, nil
+}
+
+// ExportPDF 导出整个文档为PDF
+// 返回: []byte PDF文件数据, error 错误信息
+func (s *Session) ExportPDF() ([]byte, error) {
+	if s == nil || s.Reader == nil || s.Renderer == nil || s.doc == nil {
+		return nil, fmt.Errorf("ofd document is not opened")
+	}
+	var buf bytes.Buffer
+	if err := s.Renderer.RenderToMultiPagePDF(&buf); err != nil {
+		return nil, err
+	}
+	return buf.Bytes(), nil
+}