feat: full DOCX/XLSX in-place replacement with ZIP rewrite

DOCX and XLSX files now get actual text substitution, not just
scan-and-warn:

- Reads the ZIP structure (DOCX/XLSX are ZIP files of XML)
- Decompresses DEFLATE entries via DecompressionStream API
- Finds XML text content between tags
- Applies substituteAll() to each text node
- Rewrites modified entries as uncompressed (stored) in new ZIP
- Unmodified entries preserved with original compression
- Rebuilds central directory and end-of-central-directory record

DOCX targets: word/document.xml, word/header*.xml, word/footer*.xml,
  word/comments.xml, word/endnotes.xml, word/footnotes.xml
XLSX targets: xl/sharedStrings.xml, xl/worksheets/sheet*.xml

Formatting, styles, images, formulas all preserved — only text
content between XML tags is modified. Preview mode still shows
findings before upload for user confirmation.

https://claude.ai/code/session_01SWSwDfMVij53bCTNSCLMwn
This commit is contained in:
Claude
2026-03-26 20:32:07 +00:00
parent 6598587bc4
commit c03324a871
+240 -41
View File
@@ -848,9 +848,16 @@
}
if (result.replacements.length > 0 && !result.skipped) {
// Use the substituted file
const newFile = new File([result.file], result.filename || value.name, {
type: result.file.type || value.type,
let uploadFile = result.file;
// If preview was shown and confirmed, and we have a _zip,
// build the final ZIP now
if (result._zip && result._modified) {
uploadFile = writeZipFile(result._zip);
}
const newFile = new File([uploadFile], result.filename || value.name, {
type: uploadFile.type || value.type,
});
newFormData.append(key, newFile);
allReplacements.push(...result.replacements);
@@ -937,28 +944,80 @@
}
}
// DOCX/XLSX — not supported in page world without libraries
// For now, extract what text we can and warn
// DOCX/XLSX — full in-place replacement via ZIP rewrite
if (isDOCX || isXLSX) {
try {
const text = await extractZipXMLText(file);
if (!text) return { file, filename, replacements: [], skipped: true };
const result = substituteAll(text);
const preview = {
format: ext, replacementCount: result.replacements.length,
replacements: result.replacements.slice(0, 15),
note: isDOCX ? 'Text in document will be substituted' : 'Cell values will be substituted',
};
if (options.previewMode && result.replacements.length > 0) {
return { file, filename, replacements: result.replacements, preview };
const zip = await readZipFile(file);
let totalReplacements = [];
let modified = false;
// Identify XML files containing text
const targetFiles = isDOCX
? Object.keys(zip.entries).filter(name =>
/^word\/(document|header\d*|footer\d*|comments|endnotes|footnotes)\.xml$/.test(name))
: Object.keys(zip.entries).filter(name =>
name === 'xl/sharedStrings.xml' ||
/^xl\/worksheets\/sheet\d+\.xml$/.test(name));
for (const xmlPath of targetFiles) {
const entry = zip.entries[xmlPath];
if (!entry) continue;
let xmlContent;
try {
let data = entry.rawData;
if (entry.compMethod === 8) {
data = await inflateData(data);
if (!data) continue;
}
xmlContent = new TextDecoder('utf-8').decode(data);
} catch { continue; }
// Substitute text between XML tags, preserving tags
const { xml: newXml, replacements } = substituteInXML(xmlContent);
if (replacements.length > 0) {
zip.entries[xmlPath] = {
...entry,
_modified: true,
_newData: new TextEncoder().encode(newXml),
};
totalReplacements.push(...replacements);
modified = true;
}
}
// For actual replacement, we'd need full ZIP rewrite
// For now, warn about the PPI found
if (result.modified) {
return { file, filename, replacements: result.replacements, preview };
if (!modified && !options.previewMode) {
return { file, filename, replacements: [] };
}
const preview = {
format: ext,
replacementCount: totalReplacements.length,
replacements: totalReplacements.slice(0, 15),
note: isDOCX
? 'Text in document body, headers, and footers will be substituted. Formatting preserved.'
: 'Cell values and shared strings will be substituted. Formatting and formulas preserved.',
};
if (options.previewMode && totalReplacements.length > 0) {
// Return preview first — actual replacement happens after user confirms
return { file, filename, replacements: totalReplacements, preview,
_zip: zip, _modified: modified };
}
if (modified) {
const newBlob = writeZipFile(zip);
return {
file: newBlob,
filename,
replacements: totalReplacements,
preview,
};
}
return { file, filename, replacements: [] };
} catch (e) {
console.warn('[Silent Send] DOCX/XLSX processing failed:', e);
return { file, filename, replacements: [], skipped: true, reason: e.message };
}
}
@@ -993,30 +1052,170 @@
return texts.join('\n');
}
/**
* Extract text from DOCX/XLSX XML entries.
*/
async function extractZipXMLText(file) {
// Minimal: read the file as text and find XML text content
// This is a rough extraction — better than nothing
try {
const buffer = await file.arrayBuffer();
const bytes = new Uint8Array(buffer);
const str = new TextDecoder('latin1').decode(bytes);
// Find text between XML tags
const texts = [];
const re = />([^<]{3,})</g;
let m;
while ((m = re.exec(str)) !== null) {
const text = m[1].trim();
if (text && !/^[\x00-\x1f\x80-\xff]+$/.test(text)) {
texts.push(text);
}
// ============================================================
// ZIP Read/Write — inline for page world (no module imports)
// Handles DOCX (ZIP of XML) and XLSX (ZIP of XML) files.
// ============================================================
async function readZipFile(file) {
const buffer = await file.arrayBuffer();
const bytes = new Uint8Array(buffer);
const entries = {};
// Find end of central directory
let eocdOff = -1;
for (let i = bytes.length - 22; i >= 0; i--) {
if (bytes[i] === 0x50 && bytes[i+1] === 0x4b &&
bytes[i+2] === 0x05 && bytes[i+3] === 0x06) {
eocdOff = i; break;
}
return texts.join(' ');
} catch {
return '';
}
if (eocdOff === -1) throw new Error('Not a valid ZIP');
const dv = new DataView(buffer);
const cdOff = dv.getUint32(eocdOff + 16, true);
const cdCount = dv.getUint16(eocdOff + 10, true);
let off = cdOff;
for (let i = 0; i < cdCount; i++) {
if (dv.getUint32(off, true) !== 0x02014b50) break;
const compMethod = dv.getUint16(off + 10, true);
const crc32 = dv.getUint32(off + 16, true);
const compSize = dv.getUint32(off + 20, true);
const uncompSize = dv.getUint32(off + 24, true);
const nameLen = dv.getUint16(off + 28, true);
const extraLen = dv.getUint16(off + 30, true);
const commentLen = dv.getUint16(off + 32, true);
const localOff = dv.getUint32(off + 42, true);
const name = new TextDecoder().decode(bytes.slice(off + 46, off + 46 + nameLen));
const lNameLen = dv.getUint16(localOff + 26, true);
const lExtraLen = dv.getUint16(localOff + 28, true);
const dataOff = localOff + 30 + lNameLen + lExtraLen;
entries[name] = {
compMethod, crc32, compSize, uncompSize,
rawData: bytes.slice(dataOff, dataOff + compSize),
};
off += 46 + nameLen + extraLen + commentLen;
}
return { entries, _buffer: buffer };
}
function writeZipFile(zip) {
const parts = [];
const cdEntries = [];
let offset = 0;
for (const [name, entry] of Object.entries(zip.entries)) {
const nameBytes = new TextEncoder().encode(name);
let data;
let compMethod;
if (entry._modified && entry._newData) {
// Modified — store uncompressed
data = entry._newData;
compMethod = 0; // stored
} else {
// Unmodified — keep original
data = entry.rawData;
compMethod = entry.compMethod;
}
const uncompSize = entry._modified ? data.length : entry.uncompSize;
const compSize = data.length;
// Local file header (30 + name)
const lh = new Uint8Array(30 + nameBytes.length);
const lv = new DataView(lh.buffer);
lv.setUint32(0, 0x04034b50, true);
lv.setUint16(4, 20, true);
lv.setUint16(8, compMethod, true);
lv.setUint32(18, compSize, true);
lv.setUint32(22, uncompSize, true);
lv.setUint16(26, nameBytes.length, true);
lh.set(nameBytes, 30);
// Central directory entry (46 + name)
const cd = new Uint8Array(46 + nameBytes.length);
const cv = new DataView(cd.buffer);
cv.setUint32(0, 0x02014b50, true);
cv.setUint16(4, 20, true);
cv.setUint16(6, 20, true);
cv.setUint16(10, compMethod, true);
cv.setUint32(20, compSize, true);
cv.setUint32(24, uncompSize, true);
cv.setUint16(28, nameBytes.length, true);
cv.setUint32(42, offset, true);
cd.set(nameBytes, 46);
cdEntries.push(cd);
parts.push(lh, data);
offset += lh.length + data.length;
}
const cdStart = offset;
let cdSize = 0;
for (const cd of cdEntries) {
parts.push(cd);
cdSize += cd.length;
}
const eocd = new Uint8Array(22);
const ev = new DataView(eocd.buffer);
ev.setUint32(0, 0x06054b50, true);
ev.setUint16(8, cdEntries.length, true);
ev.setUint16(10, cdEntries.length, true);
ev.setUint32(12, cdSize, true);
ev.setUint32(16, cdStart, true);
parts.push(eocd);
return new Blob(parts, { type: 'application/octet-stream' });
}
/**
* Decompress DEFLATE data using DecompressionStream API.
*/
async function inflateData(data) {
if (typeof DecompressionStream === 'undefined') return null;
try {
const ds = new DecompressionStream('deflate');
const writer = ds.writable.getWriter();
const reader = ds.readable.getReader();
writer.write(data);
writer.close();
const chunks = [];
while (true) {
const { done, value } = await reader.read();
if (done) break;
chunks.push(value);
}
const total = chunks.reduce((s, c) => s + c.length, 0);
const result = new Uint8Array(total);
let pos = 0;
for (const c of chunks) { result.set(c, pos); pos += c.length; }
return result;
} catch { return null; }
}
/**
* Find text between XML tags and apply substitution.
* Preserves all XML structure — only modifies text content.
*/
function substituteInXML(xml) {
const allReplacements = [];
const newXml = xml.replace(/>([^<]+)</g, (match, textContent) => {
if (!textContent || textContent.trim().length < 2) return match;
const result = substituteAll(textContent);
if (result.modified) {
allReplacements.push(...result.replacements);
return '>' + result.text + '<';
}
return match;
});
return { xml: newXml, replacements: allReplacements };
}
// ============================================================