feat: manually mirror opencoze's code from bytedance

Change-Id: I09a73aadda978ad9511264a756b2ce51f5761adf

backend/infra/impl/document/parser/builtin/parse_xlsx.go

@@ -0,0 +1,78 @@
+/*
+ * Copyright 2025 coze-dev Authors
+ *
+ * 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 builtin
+
+import (
+	"context"
+	"io"
+
+	"github.com/cloudwego/eino/components/document/parser"
+	"github.com/cloudwego/eino/schema"
+	"github.com/xuri/excelize/v2"
+
+	contract "github.com/coze-dev/coze-studio/backend/infra/contract/document/parser"
+)
+
+func parseXLSX(config *contract.Config) parseFn {
+	return func(ctx context.Context, reader io.Reader, opts ...parser.Option) (docs []*schema.Document, err error) {
+		f, err := excelize.OpenReader(reader)
+		if err != nil {
+			return nil, err
+		}
+
+		sheetID := 0
+		if config.ParsingStrategy.SheetID != nil {
+			sheetID = *config.ParsingStrategy.SheetID
+		}
+
+		rows, err := f.Rows(f.GetSheetName(sheetID))
+		if err != nil {
+			return nil, err
+		}
+
+		iter := &xlsxIterator{rows, 0}
+
+		return parseByRowIterator(iter, config, opts...)
+	}
+}
+
+type xlsxIterator struct {
+	rows         *excelize.Rows
+	firstRowSize int
+}
+
+func (x *xlsxIterator) NextRow() (row []string, end bool, err error) {
+	end = !x.rows.Next()
+	if end {
+		return nil, end, nil
+	}
+
+	row, err = x.rows.Columns()
+	if err != nil {
+		return nil, false, err
+	}
+
+	if x.firstRowSize == 0 {
+		x.firstRowSize = len(row)
+	} else if x.firstRowSize > len(row) {
+		row = append(row, make([]string, x.firstRowSize-len(row))...)
+	} else if x.firstRowSize < len(row) {
+		row = row[:x.firstRowSize]
+	}
+
+	return row, false, nil
+}