修正导出文档内容回写与样式保留

backend/services/document_export.py

@@ -1,4 +1,5 @@
 from io import BytesIO
+from copy import deepcopy
 
 from docx import Document
 from docx.document import Document as DocumentObject
@@ -38,36 +39,103 @@ def _clear_paragraph(paragraph: Paragraph):
             element.remove(child)
 
 
-def _append_paragraph_after(paragraph: Paragraph, text: str, style_name: str | None = None) -> Paragraph:
+def _copy_paragraph_format(target: Paragraph, source: Paragraph | None):
+    if source is None:
+        return
+    source_ppr = source._element.pPr
+    if source_ppr is not None:
+        target._element.insert(0, deepcopy(source_ppr))
+
+
+def _copy_run_format(target_run, source_paragraph: Paragraph | None):
+    if source_paragraph is None:
+        return
+    for source_run in source_paragraph.runs:
+        if source_run._element.rPr is not None:
+            target_run._element.insert(0, deepcopy(source_run._element.rPr))
+            break
+
+
+def _append_paragraph_after(
+    paragraph: Paragraph,
+    text: str,
+    style_name: str | None = None,
+    template_paragraph: Paragraph | None = None,
+) -> Paragraph:
     new_p = OxmlElement("w:p")
     paragraph._element.addnext(new_p)
     new_para = Paragraph(new_p, paragraph._parent)
+    _copy_paragraph_format(new_para, template_paragraph)
     if style_name:
         try:
             new_para.style = style_name
         except Exception:
             pass
     if text:
-        new_para.add_run(text)
+        run = new_para.add_run(text)
+        _copy_run_format(run, template_paragraph)
     return new_para
 
 
-def _append_table_after(paragraph: Paragraph, rows: list[list[str]], headers: list[str] | None = None):
+def _set_cell_text_with_template(cell, value: str, template_paragraph: Paragraph | None = None):
+    if not cell.paragraphs:
+        cell.text = value
+        return
+    paragraph = cell.paragraphs[0]
+    _clear_paragraph(paragraph)
+    run = paragraph.add_run(value)
+    _copy_run_format(run, template_paragraph)
+
+
+def _resize_table_rows(table: Table, row_count: int):
+    current_rows = len(table.rows)
+    if current_rows == 0:
+        return
+    if current_rows < row_count:
+        template_row = table.rows[-1]._tr
+        for _ in range(row_count - current_rows):
+            table._tbl.append(deepcopy(template_row))
+    elif current_rows > row_count:
+        for _ in range(current_rows - row_count):
+            table._tbl.remove(table.rows[-1]._tr)
+
+
+def _fill_table(table: Table, matrix: list[list[str]]):
+    if not matrix:
+        return
+    _resize_table_rows(table, len(matrix))
+    template_cell_paragraph = table.rows[0].cells[0].paragraphs[0] if table.rows and table.rows[0].cells else None
+    for row_index, row_values in enumerate(matrix):
+        row = table.rows[row_index]
+        for col_index, cell in enumerate(row.cells):
+            value = row_values[col_index] if col_index < len(row_values) else ""
+            _set_cell_text_with_template(cell, value, template_cell_paragraph)
+
+
+def _append_table_after(
+    paragraph: Paragraph,
+    rows: list[list[str]],
+    headers: list[str] | None = None,
+    template_table: Table | None = None,
+):
+    matrix = [headers, *rows] if headers else rows
+    if template_table is not None:
+        cloned_tbl = deepcopy(template_table._tbl)
+        paragraph._element.addnext(cloned_tbl)
+        cloned_table = Table(cloned_tbl, paragraph._parent)
+        _fill_table(cloned_table, matrix)
+        return cloned_table
+
     container = paragraph._parent
-    table = container.add_table(rows=1, cols=max(len(headers or []), len(rows[0]) if rows else 1))
+    table = container.add_table(rows=max(len(matrix), 1), cols=max(len(headers or []), len(rows[0]) if rows else 1))
     if headers:
-        header_cells = table.rows[0].cells
+        for row_index, row_values in enumerate(matrix):
-        for index, value in enumerate(headers):
+            for index, value in enumerate(row_values):
-            header_cells[index].text = value
+                table.rows[row_index].cells[index].text = value
-    else:
+    elif rows:
-        if rows:
+        for row_index, row_values in enumerate(matrix):
-            first = rows.pop(0)
+            for index, value in enumerate(row_values):
-            for index, value in enumerate(first):
+                table.rows[row_index].cells[index].text = value
-                table.rows[0].cells[index].text = value
-    for row in rows:
-        new_row = table.add_row().cells
-        for index, value in enumerate(row):
-            new_row[index].text = value
 
     tbl = table._tbl
     tbl.getparent().remove(tbl)
@@ -87,19 +155,25 @@ def _append_empty_paragraph_after_table(table: Table, style_name: str | None = N
     return new_para
 
 
-def _find_heading_paragraph(document: DocumentObject, heading_text: str) -> Paragraph | None:
+def _find_heading_paragraph(document: DocumentObject, heading_text: str, after_element=None) -> Paragraph | None:
+    started = after_element is None
     for block in _iter_block_items(document):
         if isinstance(block, Paragraph) and _is_heading(block) and block.text.strip() == heading_text.strip():
+            if started:
                 return block
+        if after_element is not None and block._element == after_element:
+            started = True
     return None
 
 
-def _replace_section_content(document: DocumentObject, heading_title: str, content: dict):
+def _replace_section_content(document: DocumentObject, heading_title: str, content: dict, after_element=None):
-    heading = _find_heading_paragraph(document, heading_title)
+    heading = _find_heading_paragraph(document, heading_title, after_element)
     if heading is None:
-        return
+        return after_element
 
     first_body_style = None
+    paragraph_template = None
+    table_template = None
     current = heading._element.getnext()
     blocks_to_remove = []
     while current is not None:
@@ -109,9 +183,14 @@ def _replace_section_content(document: DocumentObject, heading_title: str, conte
                 break
             if first_body_style is None and current_paragraph.style is not None:
                 first_body_style = current_paragraph.style.name
+            if paragraph_template is None:
+                paragraph_template = current_paragraph
             blocks_to_remove.append(current_paragraph)
         elif isinstance(current, CT_Tbl):
-            blocks_to_remove.append(Table(current, heading._parent))
+            current_table = Table(current, heading._parent)
+            if table_template is None:
+                table_template = current_table
+            blocks_to_remove.append(current_table)
         current = current.getnext()
 
     for block in blocks_to_remove:
@@ -124,17 +203,31 @@ def _replace_section_content(document: DocumentObject, heading_title: str, conte
         if block_type == "table":
             rows = [list(row) for row in block.get("rows", [])]
             headers = block.get("headers") or []
-            table = _append_table_after(insert_after, rows, headers)
+            table = _append_table_after(insert_after, rows, headers, table_template)
             insert_after = _append_empty_paragraph_after_table(table, first_body_style)
         else:
             text = block.get("text", "")
-            insert_after = _append_paragraph_after(insert_after, text, first_body_style)
+            text_parts = [item for item in text.split("\n") if item] or [text]
+            for text_part in text_parts:
+                insert_after = _append_paragraph_after(
+                    insert_after,
+                    text_part,
+                    first_body_style,
+                    paragraph_template,
+                )
+    return heading._element
 
 
 def export_document_bytes(template_bytes: bytes, logs: list[dict]) -> bytes:
     document = Document(BytesIO(template_bytes))
+    last_heading_element = None
     for item in logs:
-        _replace_section_content(document, item["title"], item["content"])
+        last_heading_element = _replace_section_content(
+            document,
+            item["title"],
+            item["content"],
+            last_heading_element,
+        )
 
     output = BytesIO()
     document.save(output)

docs/tasks/task_detail_2026_07_02.md

@@ -208,3 +208,14 @@
     2. 调整参考附件序列化方法，将 `created_at` 统一转为 ISO 字符串后再写入任务快照 JSON。
     3. 执行后端语法检查，确认修复稳定。
 - **执行结果**: 当前生成任务提交时不会再因为附件记录中的 `datetime` 字段导致 JSON 序列化失败。
+
+## 会话 ID: local-20260702182751
+- [2026-07-02 18:27:51]
+- **执行原因**: 用户反馈导出的模板与原模板几乎一致，AI 结果没有正确写入，同时模板样式在导出后发生明显偏移。
+- **执行过程**:
+    1. 检查导出链路，确认原实现采用“删除原内容后新建普通段落/表格”的方式回写，容易导致标题命中不稳和样式丢失。
+    2. 重构导出服务的段落替换逻辑，改为按标题顺序匹配模板中的章节，减少重复标题导致的误替换风险。
+    3. 调整导出时的文本回写方式，优先复用模板原有段落的段落属性与首个 run 的字体样式，再写入 AI 返回文本。
+    4. 调整导出时的表格回写方式，优先克隆模板原有表格结构并填充新数据，尽量保留表格外观和基础样式。
+    5. 执行后端语法检查，确认导出服务改动稳定。
+- **执行结果**: 当前导出链路已改为“尽量复用模板原始段落/表格样式后写入 AI 内容”，比此前的新建空白内容块方式更接近原模板样式，也更容易把 AI 结果正确写回文档。