# Roadmap

Where SharpCell is going, in the order the work is planned. Each step ships when its tests pass
and its results are checked against Microsoft Excel. Dates are not promised; the project has one
maintainer.

## Released

| Version | What |
|---|---|
| 0.1 | The engine: parser, dependency graph, recalculation, dynamic arrays, LET/LAMBDA, reading .xlsx |
| 0.2 | Tables and structured references (`Sales[Units]`), hidden rows in `SUBTOTAL` and `AGGREGATE` |
| 0.3 | Saving recalculated values back into the file a workbook was read from |
| 0.4 | API for applications: walking and writing cells, custom functions, changed cells, cloning templates |
| 0.5 | Number formats and `Cell.Text`; iterative calculation of circular references |
| 0.6 | Cell styles, column widths, row heights, merged cells, frozen panes and gridlines, read from files |
| 0.7 | Saving everything the model holds, workbooks built in code, .xlsm files, inserting and deleting rows and columns; functions as values, `GROUPBY`, `PIVOTBY`, `PERCENTOF` |
| 0.8 | `Cell.Input`: a cell as typed in Excel |
| 0.9 | Building workbooks: filling sheets from collections and `DataTable`s, hyperlinks, data validation, sheet and workbook protection, locked and hidden cells |
| 0.10 | Copying cells as Excel pastes them, formulas, links and data validation following (`CellRange.CopyTo`) |

## Now: 0.11, rules on cells

- Done: conditional formatting, read, added and saved. SharpCell also tells which cells a rule
  applies to and how they look (`Cell.ConditionalFormats`, `Cell.DisplayStyle`), since it
  calculates the formulas Excel would. Colour scales, data bars and icon sets are kept, not drawn.
- Done: notes, read, added and saved.
- Done: page setup: orientation, margins, print area, print titles and page breaks.
- Done: inserting and deleting cells with Excel's "Shift cells down / right / up / left".
- Benchmarks against EPPlus and ClosedXML: loading, recalculating and saving large workbooks.

## Later

- Cells that break their data validation, found by calculating the rules (Excel's Circle Invalid Data).
- Sorting a range, with formulas moving as Excel moves them.
- Fitting column widths to their contents. This needs font metrics, which the engine does not
  carry; it may come as a separate package.
- Resizing and renaming tables, and inserting columns into them.
- Removing and renaming sheets.
- Rich text in cells.

## Not planned

Creating charts, pivot tables, pictures or shapes (a file's own are kept when it is saved),
running macros, .xls and .xlsb files, and encrypted files.