diff --git a/.~lock.MAQUETTES ANALYSES FINANCIERES VUE SYNTHETIQUE VERSION LONGUE.xlsx# b/.~lock.MAQUETTES ANALYSES FINANCIERES VUE SYNTHETIQUE VERSION LONGUE.xlsx#
new file mode 100644
index 0000000..e6b29f2
--- /dev/null
+++ b/.~lock.MAQUETTES ANALYSES FINANCIERES VUE SYNTHETIQUE VERSION LONGUE.xlsx#	
@@ -0,0 +1 @@
+,sanchezn,pc-sanchezn,17.02.2026 15:16,/home/sanchezn/.local/share/onlyoffice;
\ No newline at end of file
diff --git a/Cargo.toml b/Cargo.toml
index dd82485..647199d 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -3,6 +3,9 @@ name = "xlsxtocsv"
 version = "0.1.0"
 edition = "2024"
 
+[features]
+csv = []
+
 [dependencies]
 clap = { version = "4.5.48", features = ["derive"] }
 rhai = "1.23.6"
diff --git a/MAQUETTES ANALYSES FINANCIERES VUE SYNTHETIQUE VERSION LONGUE.xlsx b/MAQUETTES ANALYSES FINANCIERES VUE SYNTHETIQUE VERSION LONGUE.xlsx
index a4559b0..9752ad7 100644
Binary files a/MAQUETTES ANALYSES FINANCIERES VUE SYNTHETIQUE VERSION LONGUE.xlsx and b/MAQUETTES ANALYSES FINANCIERES VUE SYNTHETIQUE VERSION LONGUE.xlsx differ
diff --git a/src/arguments.rs b/src/arguments.rs
index 8a7b609..c725c34 100644
--- a/src/arguments.rs
+++ b/src/arguments.rs
@@ -2,11 +2,12 @@ use clap::Parser;
 use clap::ValueEnum;
 use std::fmt;
 
-#[derive(Clone, Debug, ValueEnum)]
+#[derive(Clone, Debug, ValueEnum, Default)]
 pub enum FillMergedCells {
     None,
     Horizontal,
     Vertical,
+    #[default]
     Both,
 }
 
@@ -21,11 +22,12 @@ impl fmt::Display for FillMergedCells {
     }
 }
 
-#[derive(Clone, Debug, ValueEnum)]
+#[derive(Clone, Debug, ValueEnum, Default)]
 pub enum IncludeHidden {
     None,
     Rows,
     Columns,
+    #[default]
     Both,
 }
 
@@ -39,11 +41,12 @@ impl fmt::Display for IncludeHidden {
         }
     }
 }
-#[derive(Clone, Debug, ValueEnum)]
+#[derive(Clone, Debug, ValueEnum, Default)]
 pub enum TrimSpaces {
     End,
     Start,
     Both,
+    #[default]
     None,
 }
 
@@ -62,10 +65,11 @@ impl fmt::Display for TrimSpaces {
     }
 }
 
-#[derive(Clone, Debug, ValueEnum)]
+#[derive(Clone, Debug, ValueEnum, Default)]
 pub enum NumberRows {
     AsIs,
     Sequential,
+    #[default]
     None,
 }
 
@@ -106,6 +110,9 @@ pub struct RawArguments {
     /// Chosse worksheet
     #[arg(short, long, default_value_t = String::from("0"))]
     pub worksheet: String,
+    /// Choose active worksheet at save time in excel
+    #[arg(short, long, default_value_t = false)]
+    pub active_worksheet: bool,
     /// Trim white spaces at end of cells
     #[arg(short, long, default_value_t = TrimSpaces::None)]
     pub trim: TrimSpaces,
@@ -137,15 +144,17 @@ pub struct Arguments {
     /// Replace separator char in cells by
     pub replace_separator_by: Option<String>,
     /// include hidden lines to output
-    pub include_hidden: IncludeHidden,
+    // pub include_hidden: IncludeHidden,
     pub include_hidden_rows: bool,
     pub include_hidden_columns: bool,
     /// If merged cells, fill horizontally, vertically, both, or none
-    pub fill_merged_cells: FillMergedCells,
+    // pub fill_merged_cells: FillMergedCells,
     pub fill_merged_cells_horizontal: bool,
     pub fill_merged_cells_vertical: bool,
     /// Chosse worksheet
     pub worksheet: String,
+    /// Use the worksheet that was active when the file was last saved
+    pub active_worksheet: bool,
     /// Trim white spaces at end of cells
     pub trim: TrimSpaces,
     /// number the rows in first cell of each line
@@ -167,6 +176,29 @@ impl Arguments {
     }
 }
 
+impl Default for Arguments {
+    fn default() -> Self {
+        Self {
+            file: Default::default(),
+            list_worksheets: Default::default(),
+            separator: ';',
+            replace_separator_by: Default::default(),
+            include_hidden_rows: Default::default(),
+            include_hidden_columns: Default::default(),
+            fill_merged_cells_horizontal: Default::default(),
+            fill_merged_cells_vertical: Default::default(),
+            worksheet: String::from("0"),
+            active_worksheet: false,
+            trim: Default::default(),
+            number_rows: Default::default(),
+            skip_rows: Default::default(),
+            end_of_line: String::from("\n"),
+            replace_end_of_line_by: Default::default(),
+            filter: Default::default(),
+        }
+    }
+}
+
 impl From<RawArguments> for Arguments {
     fn from(raw: RawArguments) -> Self {
         let (include_hidden_columns, include_hidden_rows) = match raw.include_hidden {
@@ -189,13 +221,12 @@ impl From<RawArguments> for Arguments {
             list_worksheets: raw.list_worksheets,
             separator: raw.separator,
             replace_separator_by: raw.replace_separator_by,
-            include_hidden: raw.include_hidden,
             include_hidden_columns,
             include_hidden_rows,
-            fill_merged_cells: raw.fill_merged_cells,
             fill_merged_cells_horizontal,
             fill_merged_cells_vertical,
             worksheet: raw.worksheet,
+            active_worksheet: raw.active_worksheet,
             trim: raw.trim,
             number_rows: raw.number_rows,
             skip_rows: raw.skip_rows,
@@ -205,3 +236,31 @@ impl From<RawArguments> for Arguments {
         }
     }
 }
+
+pub trait IntoArgs {
+    fn into_args(self) -> Arguments;
+}
+
+impl IntoArgs for String {
+    fn into_args(self) -> Arguments {
+        Arguments {
+            file: self,
+            ..Default::default()
+        }
+    }
+}
+
+impl IntoArgs for &str {
+    fn into_args(self) -> Arguments {
+        Arguments {
+            file: self.to_string(),
+            ..Default::default()
+        }
+    }
+}
+
+impl IntoArgs for Arguments {
+    fn into_args(self) -> Arguments {
+        self
+    }
+}
diff --git a/src/lib.rs b/src/lib.rs
index 8d16fa1..d6d4d5f 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,3 +1,7 @@
 pub mod arguments;
 pub mod error;
 pub mod xlsx;
+pub mod xlsx_builder;
+
+//#[cfg(feature = "csv")]
+pub mod xlsx_to_csv;
diff --git a/src/main.rs b/src/main.rs
index 7426b6e..6af5368 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,8 +1,14 @@
-use xlsxtocsv::{arguments::Arguments, xlsx::xlsxtocsv};
+use xlsxtocsv::{arguments::Arguments, xlsx::XlsxReader};
 
 fn main() {
     let args = Arguments::parse();
-    if let Err(error) = xlsxtocsv(&args) {
-        eprintln!("{}", error);
+    /*    if let Err(error) = xlsxtocsv(&args) {
+            eprintln!("{}", error);
+    }*/
+
+    let xlsxreader = XlsxReader::new(args).unwrap();
+    let reader = xlsxreader.to_csv();
+    for line in reader {
+        println!("{line}");
     }
 }
diff --git a/src/xlsx.rs b/src/xlsx.rs
index b6eea9b..2be26af 100644
--- a/src/xlsx.rs
+++ b/src/xlsx.rs
@@ -1,19 +1,140 @@
+use std::cell::RefCell;
 use std::io::{BufWriter, Write, stdout};
 use std::path::Path;
-use umya_spreadsheet::{Cell, Range, Worksheet, reader};
+use umya_spreadsheet::{Cell, Range, Spreadsheet, Worksheet, reader};
 
-use crate::arguments::{Arguments, NumberRows, TrimSpaces};
+use crate::arguments::{Arguments, IntoArgs, NumberRows, TrimSpaces};
 use crate::error::Error;
 
+pub struct XlsxReader {
+    pub(crate) args: Arguments,
+    pub(crate) book: Spreadsheet,
+    pub(crate) sheet_index: usize,
+    pub worksheet_dimensions: RefCell<Option<(u32, u32)>>,
+}
+
+impl XlsxReader {
+    pub fn new(args: impl IntoArgs) -> Result<Self, Error> {
+        let mut args = args.into_args();
+
+        let book = reader::xlsx::read(Path::new(args.file.as_str()))?;
+
+        if args.active_worksheet && args.worksheet == "0" {
+            let sheetname = book.get_active_sheet().get_name();
+            args.worksheet = String::from(sheetname);
+        }
+        let sheet_index = Self::get_worksheet_index(&book, args.worksheet.as_str())?;
+
+        Ok(XlsxReader {
+            args,
+            book,
+            sheet_index,
+            worksheet_dimensions: RefCell::new(None),
+        })
+    }
+
+    pub fn list_worksheets(&self) -> Result<Vec<(usize, String)>, Error> {
+        let sheets = self.book.get_sheet_collection();
+        let mut res = vec![];
+
+        for (i, sheet) in sheets.iter().enumerate() {
+            res.push((i, String::from(sheet.get_name())));
+        }
+        Ok(res)
+    }
+
+    pub fn to_lazyframe(&self) {
+        let sheet = self.get_sheet();
+        println!("sheetname: {}", sheet.get_name());
+    }
+
+    pub(crate) fn get_worksheet_index(
+        book: &Spreadsheet,
+        worksheet_name: &str,
+    ) -> Result<usize, Error> {
+        let sheet_index = if book.get_sheet_by_name(worksheet_name).is_some() {
+            // Le nom existe - trouve son index
+            book.get_sheet_collection()
+                .iter()
+                .position(|s| s.get_name() == worksheet_name)
+                .ok_or("cannot find sheet index")?
+        } else if let Ok(num) = worksheet_name.parse::<usize>() {
+            // Pas de nom correspondant, essaye comme numéro
+            if book.get_sheet(&num).is_none() {
+                return Err("cannot open sheet".into());
+            }
+            num
+        } else {
+            return Err("cannot open sheet".into());
+        };
+        Ok(sheet_index)
+    }
+
+    pub(crate) fn get_sheet(&self) -> &Worksheet {
+        self.book.get_sheet(&self.sheet_index).unwrap()
+    }
+
+    pub(crate) fn get_worksheet_dimensions(&self) -> (u32, u32) {
+        if self.worksheet_dimensions.borrow().is_none() {
+            let mut num_cols = 0;
+            let mut num_rows = 0;
+
+            for cell in self.get_sheet().get_cell_collection() {
+                let value = get_value(cell); //.get_formatted_value();
+
+                if value.is_empty() {
+                    continue;
+                }
+
+                let coord = cell.get_coordinate();
+                let col_num = *coord.get_col_num();
+                let row_num = *coord.get_row_num();
+                if col_num > num_cols {
+                    num_cols = col_num;
+                }
+                if row_num > num_rows {
+                    num_rows = row_num;
+                }
+            }
+            let mut dim = self.worksheet_dimensions.borrow_mut();
+            *dim = Some((num_cols, num_rows));
+        }
+        let (c, r) = self.worksheet_dimensions.borrow().unwrap();
+        (c, r)
+    }
+
+    pub(crate) fn get_row(&self, row_num: u32) -> Vec<String> {
+        let num_cols = self.get_worksheet_dimensions().0 as usize;
+        let sheet = self.get_sheet();
+        let row = sheet.get_collection_by_row(&row_num);
+
+        let mut res = vec![String::new(); num_cols];
+
+        for cell in row {
+            let txt = cell.get_formatted_value();
+            let coord = cell.get_coordinate();
+            let col = *coord.get_col_num() - 1;
+            res[col as usize] = txt;
+        }
+
+        res
+    }
+}
+
+pub fn list_worksheets(book: Spreadsheet) -> Result<Vec<(usize, String)>, Error> {
+    let sheets = book.get_sheet_collection();
+    let mut res = vec![];
+    for (i, sheet) in sheets.iter().enumerate() {
+        res.push((i, String::from(sheet.get_name())));
+    }
+    Ok(res)
+}
+
 pub fn xlsxtocsv(args: &Arguments) -> Result<(), Error> {
     let book = reader::xlsx::read(Path::new(&args.file))?;
 
     if args.list_worksheets {
         println!("List of worksheets :");
-        let sheets = book.get_sheet_collection();
-        for (i, sheet) in sheets.iter().enumerate() {
-            println!(" {:3}: {}", i, sheet.get_name());
-        }
 
         return Ok(());
     }
diff --git a/src/xlsx_builder.rs b/src/xlsx_builder.rs
new file mode 100644
index 0000000..6bfcccb
--- /dev/null
+++ b/src/xlsx_builder.rs
@@ -0,0 +1,113 @@
+use crate::{
+    arguments::{FillMergedCells, IncludeHidden, NumberRows, TrimSpaces},
+    error::Error,
+    xlsx::XlsxReader,
+};
+
+impl XlsxReader {
+    pub fn with_separator(mut self, separator: char) -> Self {
+        self.args.separator = separator;
+        self
+    }
+
+    pub fn with_replace_separator_by(mut self, replacement: String) -> Self {
+        self.args.replace_separator_by = Some(replacement);
+        self
+    }
+
+    pub fn with_include_hidden_columns(mut self, include: bool) -> Self {
+        self.args.include_hidden_columns = include;
+        self
+    }
+
+    pub fn with_include_hidden_rows(mut self, include: bool) -> Self {
+        self.args.include_hidden_rows = include;
+        self
+    }
+
+    pub fn with_include_hidden(mut self, include: IncludeHidden) -> Self {
+        let (col, row) = match include {
+            IncludeHidden::None => (false, false),
+            IncludeHidden::Rows => (false, true),
+            IncludeHidden::Columns => (true, false),
+            IncludeHidden::Both => (true, true),
+        };
+        self.args.include_hidden_columns = col;
+        self.args.include_hidden_rows = row;
+        self
+    }
+
+    pub fn with_fill_merged_cells_vertical(mut self, merge: bool) -> Self {
+        self.args.fill_merged_cells_vertical = merge;
+        self
+    }
+
+    pub fn with_fill_merged_cells_horizontal(mut self, merge: bool) -> Self {
+        self.args.fill_merged_cells_horizontal = merge;
+        self
+    }
+
+    pub fn with_fill_merged_cells(mut self, mode: FillMergedCells) -> Self {
+        let (horizontal, vertical) = match mode {
+            FillMergedCells::None => (false, false),
+            FillMergedCells::Horizontal => (true, false),
+            FillMergedCells::Vertical => (false, true),
+            FillMergedCells::Both => (true, true),
+        };
+        self.args.fill_merged_cells_horizontal = horizontal;
+        self.args.fill_merged_cells_vertical = vertical;
+        self
+    }
+
+    pub fn with_worksheet(mut self, worksheet_name: &str) -> Result<Self, Error> {
+        self.args.worksheet = String::from(worksheet_name);
+
+        self.sheet_index = Self::get_worksheet_index(&self.book, worksheet_name)?;
+        Ok(self)
+    }
+
+    pub fn with_active_worksheet(mut self, active_worksheet: bool) -> Self {
+        self.args.active_worksheet = active_worksheet;
+        self
+    }
+
+    pub fn with_trim_start(mut self) -> Self {
+        self.args.trim = match self.args.trim {
+            TrimSpaces::End => TrimSpaces::Both,
+            TrimSpaces::Start => TrimSpaces::Start,
+            TrimSpaces::Both => TrimSpaces::Both,
+            TrimSpaces::None => TrimSpaces::Start,
+        };
+        self
+    }
+
+    pub fn with_trim_end(mut self) -> Self {
+        self.args.trim = match self.args.trim {
+            TrimSpaces::End => TrimSpaces::End,
+            TrimSpaces::Start => TrimSpaces::Both,
+            TrimSpaces::Both => TrimSpaces::Both,
+            TrimSpaces::None => TrimSpaces::End,
+        };
+        self
+    }
+
+    pub fn with_number_rows(mut self, number_rows: NumberRows) -> Self {
+        self.args.number_rows = number_rows;
+        self
+    }
+
+    pub fn with_skip_rows(mut self, skip: u32) -> Self {
+        self.args.skip_rows = skip;
+        self
+    }
+
+    pub fn with_end_of_line(mut self, eol: String) -> Self {
+        self.args.end_of_line = eol;
+        self
+    }
+
+    pub fn with_replace_end_of_line_by(mut self, replacement: String) -> Self {
+        self.args.replace_end_of_line_by = Some(replacement);
+        self
+    }
+}
diff --git a/src/xlsx_to_csv.rs b/src/xlsx_to_csv.rs
new file mode 100644
index 0000000..df53cab
--- /dev/null
+++ b/src/xlsx_to_csv.rs
@@ -0,0 +1,35 @@
+use crate::xlsx::XlsxReader;
+
+pub struct XlsxToCsvLines<'a> {
+    xlsx_reader: &'a XlsxReader,
+    current_row: u32,
+    num_rows: u32,
+}
+
+impl<'a> Iterator for XlsxToCsvLines<'a> {
+    type Item = String;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        if self.current_row > self.num_rows {
+            return None;
+        }
+
+        let row = self.xlsx_reader.get_row(self.current_row);
+        self.current_row += 1;
+
+        let row = row.join(";");
+
+        Some(row)
+    }
+}
+
+impl XlsxReader {
+    pub fn to_csv(&self) -> XlsxToCsvLines<'_> {
+        let num_rows = self.get_worksheet_dimensions().1;
+        XlsxToCsvLines {
+            xlsx_reader: self,
+            current_row: 0,
+            num_rows,
+        }
+    }
+}