importer feature

crates/adapters/importer/src/parsers/xlsx.rs

@@ -0,0 +1,64 @@
+use calamine::{Reader, open_workbook_from_rs, Xlsx, Data};
+use std::io::Cursor;
+use crate::{ImportError, types::ParsedFile};
+
+pub fn parse_xlsx(bytes: &[u8]) -> Result<ParsedFile, ImportError> {
+    let cursor = Cursor::new(bytes);
+    let mut workbook: Xlsx<_> = open_workbook_from_rs(cursor)
+        .map_err(|e: calamine::XlsxError| ImportError::Xlsx(e.to_string()))?;
+
+    let sheet_name = workbook.sheet_names()
+        .first()
+        .cloned()
+        .ok_or(ImportError::Empty)?;
+
+    let range = workbook.worksheet_range(&sheet_name)
+        .map_err(|e| ImportError::Xlsx(e.to_string()))?;
+
+    let mut iter = range.rows();
+
+    let header = iter.next().ok_or(ImportError::NoHeader)?;
+    let columns: Vec<String> = header.iter()
+        .map(|c| cell_to_string(c).trim().to_string())
+        .collect();
+
+    if columns.is_empty() {
+        return Err(ImportError::NoHeader);
+    }
+
+    let rows: Vec<Vec<String>> = iter
+        .map(|row| {
+            let mut cells: Vec<String> = row.iter().map(cell_to_string).collect();
+            cells.resize(columns.len(), String::new());
+            cells.truncate(columns.len());
+            cells
+        })
+        .collect();
+
+    if rows.is_empty() {
+        return Err(ImportError::Empty);
+    }
+
+    Ok(ParsedFile { columns, rows })
+}
+
+fn cell_to_string(cell: &Data) -> String {
+    match cell {
+        Data::String(s) => s.clone(),
+        Data::Float(f) => {
+            if f.fract() == 0.0 { format!("{}", *f as i64) } else { format!("{}", f) }
+        }
+        Data::Int(i) => i.to_string(),
+        Data::Bool(b) => b.to_string(),
+        Data::DateTime(dt) => {
+            // ExcelDateTime::to_ymd_hms_milli() works without the chrono feature.
+            let (year, month, day, _, _, _, _) = dt.to_ymd_hms_milli();
+            format!("{:04}-{:02}-{:02}", year, month, day)
+        }
+        Data::DateTimeIso(s) => s.clone(),
+        Data::DurationIso(s) => s.clone(),
+        Data::Empty | Data::Error(_) => String::new(),
+        // Fallback for unexpected calamine Data variants; renders as debug string
+        other => format!("{other:?}"),
+    }
+}