feat(归并文件): 归并根包文件

ofdgo_editor_package.go

@@ -17,9 +17,11 @@ package ofdgo
 import (
 	"archive/zip"
 	"bytes"
+	"compress/flate"
 	"context"
 	"encoding/xml"
 	"fmt"
+	"hash/crc32"
 	"io"
 	"maps"
 	"reflect"
@@ -28,6 +30,25 @@ import (
 	"strings"
 )
 
+// editorStagedPage 保存单次写出的压缩页面及校验值，不持有未压缩XML
+type editorStagedPage struct {
+	data     []byte
+	size     uint64
+	checksum uint32
+}
+
+// editorPageStager 复用单次保存的页面压缩器，不跨文档共享状态
+type editorPageStager struct {
+	compressor *flate.Writer
+}
+
+// editorPageEncoding 同步统计编码字节及CRC，保留实际写入错误
+type editorPageEncoding struct {
+	writer   io.Writer
+	size     uint64
+	checksum uint32
+}
+
 // sourceParts 生成编辑快照的XML和新增资源，同步清理已删除页面及附件的引用
 // 入参: ctx 取消上下文, progress 保存进度回调，预览时为nil
 // 返回: map[string][]byte 替换及新增条目, error 错误信息
@@ -810,3 +831,93 @@ func (e *Editor) sourceReader(ctx context.Context, progress editorProgress) (*Re
 	}
 	return reader, nil
 }
+
+// Write 写入页面字节并统计实际接收的部分
+// 入参: data 未压缩编码数据
+// 返回: int 实际字节数, error 写入或短写错误
+func (w *editorPageEncoding) Write(data []byte) (int, error) {
+	n, err := w.writer.Write(data)
+	w.size += uint64(n)
+	w.checksum = crc32.Update(w.checksum, crc32.IEEETable, data[:n])
+	if n != len(data) && err == nil {
+		err = io.ErrShortWrite
+	}
+	return n, err
+}
+
+// encode 边编码边压缩自产页面，同步收集引用及用字
+// 入参: editor 保存快照, page 页面内容, references 本次引用扫描
+// 返回: *editorStagedPage 压缩页面, error 编码或取消错误
+func (s *editorPageStager) encode(editor *Editor, page PageContent, references *editorReferenceScan) (*editorStagedPage, error) {
+	var data bytes.Buffer
+	if s.compressor == nil {
+		level := flate.DefaultCompression
+		if editor.output != nil && editor.output.options.Mode != CompressionUnchanged {
+			level = flate.BestCompression
+		}
+		var err error
+		s.compressor, err = flate.NewWriter(&data, level)
+		if err != nil {
+			return nil, err
+		}
+	} else {
+		s.compressor.Reset(&data)
+	}
+	output := editorPageEncoding{writer: s.compressor}
+	x := &ofdXML{encoder: xml.NewEncoder(&output), references: references}
+	if editor.output != nil {
+		x.ctx = editor.output.ctx
+	}
+	x.page(page)
+	if err := x.finish(); err != nil {
+		return nil, err
+	}
+	if err := s.compressor.Close(); err != nil {
+		return nil, err
+	}
+	if !x.checkContext() {
+		return nil, x.err
+	}
+	return &editorStagedPage{data: data.Bytes(), size: output.size, checksum: output.checksum}, nil
+}
+
+// open 流式读取暂存页面，仅用于无法完整收集编码引用的分支
+// 返回: io.ReadCloser 页面解压流
+func (p *editorStagedPage) open() io.ReadCloser {
+	return flate.NewReader(bytes.NewReader(p.data))
+}
+
+// writeStagedPage 直接写入已经压缩的自产页面，保持ZIP条目属性和取消语义
+// 入参: archive 输出归档, header 条目属性, page 暂存页面
+// 返回: error 写入、短写或取消错误
+func (e *Editor) writeStagedPage(archive *zip.Writer, header zip.FileHeader, page *editorStagedPage) error {
+	if e.output != nil && e.output.options.Mode != CompressionUnchanged {
+		if err := editorProgress(e.OnWriteProgress).report("compress", e.output.completed, 0); err != nil {
+			return err
+		}
+	}
+	prepareOutputHeader(&header, zip.Deflate, page.size, uint64(len(page.data)), page.checksum)
+	entry, err := archive.CreateRaw(&header)
+	if err != nil {
+		return err
+	}
+	for offset := 0; offset < len(page.data); {
+		if e.output != nil {
+			if err := e.output.ctx.Err(); err != nil {
+				return err
+			}
+		}
+		end := min(offset+64<<10, len(page.data))
+		if n, err := entry.Write(page.data[offset:end]); err != nil {
+			return err
+		} else if n != end-offset {
+			return io.ErrShortWrite
+		}
+		offset = end
+	}
+	if e.output != nil && e.output.options.Mode != CompressionUnchanged {
+		e.output.completed++
+		return editorProgress(e.OnWriteProgress).report("compress", e.output.completed, 0)
+	}
+	return nil
+}