feat(打印能力): 新增打印并优化界面布局

internal/webui/webui.go

@@ -423,6 +423,7 @@ type businessEngine struct {
 	currentSession *Session
 	currentEditor  *ofdgo.Editor
 	saveSnapshot   *ofdgo.Editor
+	printDocument  *ofdgo.PrintDocument
 	pendingImport  *ofdgo.Reader
 	copiedObjects  *editorClipboard
 	copiedStyle    *ofdgo.GraphicObject
@@ -7445,6 +7446,11 @@ func (c *outputContext) Err() error {
 // businessCommands 共用业务命令表
 func (e *businessEngine) businessCommands() map[string]func([]platformValue) (any, error) {
 	return map[string]func([]platformValue) (any, error){
+		"ofdgoPreparePrint":           e.preparePrint,
+		"ofdgoLayoutPrint":            e.layoutPrint,
+		"ofdgoPrintSide":              e.printSide,
+		"ofdgoPrintPDF":               e.printPDF,
+		"ofdgoDiscardPrint":           e.discardPrint,
 		"ofdgoDetectFormat":           e.detectDocumentFormat,
 		"ofdgoOpen":                   e.openDocument,
 		"ofdgoSelectDocument":         e.selectDocument,
@@ -7594,6 +7600,8 @@ func (e *businessEngine) operationContext() context.Context {
 func failureResult(err error) apiResult {
 	result := apiResult{Error: err.Error()}
 	switch {
+	case errors.Is(err, ofdgo.ErrPrintDenied):
+		result.Code, result.Error = "printDenied", "文档禁止打印"
 	case errors.Is(err, ofdgo.ErrPDFPassword):
 		result.Code, result.Error = "pdfPassword", "PDF密码缺失或错误"
 	case errors.Is(err, ofdgo.ErrCredentialsRequired):

internal/webui/webui_native.go

@@ -357,6 +357,7 @@ func (e *NativeEngine) Close() error {
 	e.gate <- struct{}{}
 	defer func() { <-e.gate }()
 	e.closed = true
+	_, _ = e.discardPrint(nil)
 	_ = e.waitRenders(context.Background())
 	e.renderIdle = nil
 	e.saveSnapshot = nil

internal/webui/webui_print.go

@@ -0,0 +1,141 @@
+// 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"
+	"encoding/json"
+	"fmt"
+
+	"github.com/xiaoqidun/ofdgo"
+)
+
+// preparePrint 从当前编辑入口创建独立打印快照，业务选项由公开库统一校验
+// 入参: args 排版选项及可选输出任务标识
+// 返回: any 纸面布局, error 快照、权限或排版错误
+func (e *businessEngine) preparePrint(args []platformValue) (any, error) {
+	if e.currentSession == nil || len(args) == 0 {
+		return nil, fmt.Errorf("ofd document is not opened")
+	}
+	var options ofdgo.PrintOptions
+	if err := json.Unmarshal([]byte(platformJSON(args[0])), &options); err != nil {
+		return nil, err
+	}
+	ctx := e.operationContext()
+	if len(args) > 1 {
+		ctx = e.newOutputContext(args[1])
+	}
+	editor := e.currentEditor
+	if editor == nil {
+		var err error
+		editor, err = e.currentSession.Reader.EditorContext(ctx)
+		if err != nil {
+			return nil, err
+		}
+	}
+	source := e.currentSession.Renderer
+	dirs, fonts := source.FontSources()
+	document, err := editor.PreparePrint(ctx, options, ofdgo.WithRenderBackends(source.Backends()), ofdgo.WithFontDirs(dirs...), ofdgo.WithFontFS(fonts...))
+	if err != nil {
+		return nil, err
+	}
+	if e.printDocument != nil {
+		_ = e.printDocument.Close()
+	}
+	e.printDocument = document
+	data, err := json.Marshal(document.Layout())
+	if err != nil {
+		return nil, err
+	}
+	return successResult(platformParseJSON(data)), nil
+}
+
+// layoutPrint 在既有快照上调整排版，预览期间不重复复制源包
+// 入参: args 新排版选项及可选输出任务标识
+// 返回: any 新纸面布局, error 状态、权限或排版错误
+func (e *businessEngine) layoutPrint(args []platformValue) (any, error) {
+	if e.printDocument == nil || len(args) == 0 {
+		return nil, fmt.Errorf("print document is not prepared")
+	}
+	var options ofdgo.PrintOptions
+	if err := json.Unmarshal([]byte(platformJSON(args[0])), &options); err != nil {
+		return nil, err
+	}
+	ctx := e.operationContext()
+	if len(args) > 1 {
+		ctx = e.newOutputContext(args[1])
+	}
+	next, err := e.printDocument.Reconfigure(ctx, options)
+	if err != nil {
+		return nil, err
+	}
+	_ = e.printDocument.Close()
+	e.printDocument = next
+	data, err := json.Marshal(next.Layout())
+	if err != nil {
+		return nil, err
+	}
+	return successResult(platformParseJSON(data)), nil
+}
+
+// printSide 按需输出一个纸面，不使用阅读区缓存或缩略图
+// 入参: args 零基纸面索引及可选输出任务标识
+// 返回: any 内嵌资源的SVG纸面, error 状态或渲染错误
+func (e *businessEngine) printSide(args []platformValue) (any, error) {
+	if e.printDocument == nil || len(args) == 0 {
+		return nil, fmt.Errorf("print document is not prepared")
+	}
+	ctx := e.operationContext()
+	if len(args) > 1 {
+		ctx = e.newOutputContext(args[1])
+	}
+	var output bytes.Buffer
+	if err := e.printDocument.RenderSVG(ctx, args[0].Int(), &output); err != nil {
+		return nil, err
+	}
+	return successResult(map[string]any{"svg": output.String()}), nil
+}
+
+// printPDF 输出和预览相同的打印布局，便于另存或交给第三方打印系统
+// 入参: args 可选输出任务标识
+// 返回: any PDF数据及媒体类型, error 状态或输出错误
+func (e *businessEngine) printPDF(args []platformValue) (any, error) {
+	if e.printDocument == nil {
+		return nil, fmt.Errorf("print document is not prepared")
+	}
+	ctx := e.operationContext()
+	if len(args) > 0 {
+		ctx = e.newOutputContext(args[0])
+	}
+	var output bytes.Buffer
+	if err := e.printDocument.WritePDF(ctx, &output); err != nil {
+		return nil, err
+	}
+	return successResult(map[string]any{"bytes": bytesToJS(output.Bytes()), "mime": "application/pdf"}), nil
+}
+
+// discardPrint 释放当前打印快照，可重复调用
+// 入参: _ 保留的调用参数
+// 返回: any 空结果, error 资源释放错误
+func (e *businessEngine) discardPrint(_ []platformValue) (any, error) {
+	if e.printDocument != nil {
+		err := e.printDocument.Close()
+		e.printDocument = nil
+		if err != nil {
+			return nil, err
+		}
+	}
+	return successResult(nil), nil
+}

internal/webui/webui_wasm.go

@@ -99,6 +99,7 @@ func (w *wasmEngines) close(args []js.Value) (any, error) {
 		return nil, nil
 	}
 	delete(w.engines, id)
+	_, _ = e.discardPrint(nil)
 	e.clearImport()
 	err := e.currentSession.Close()
 	*e = businessEngine{}