# file-overwrite-control Specification

## Purpose
TBD - created by archiving change add-file-overwrite-control. Update Purpose after archive.
## Requirements
### Requirement: ExcelService provides file overwrite control
The ExcelService SHALL provide explicit control over whether existing files should be overwritten during initialization.

#### Scenario: Create new file when file does not exist
- **WHEN** `InitExcel` is called with `overwrite=true` and file does not exist
- **THEN** method creates new file and returns success with file path

#### Scenario: Overwrite existing file when overwrite is true
- **WHEN** `InitExcel` is called with `overwrite=true` and file exists
- **THEN** method overwrites existing file and returns success with file path

#### Scenario: Throw exception when file exists and overwrite is false
- **WHEN** `InitExcel` is called with `overwrite=false` and file exists
- **THEN** method throws `IOException` with message indicating file already exists

#### Scenario: Create file when overwrite is false and file does not exist
- **WHEN** `InitExcel` is called with `overwrite=false` and file does not exist
- **THEN** method creates new file and returns success with file path

#### Scenario: Preserve existing file behavior when overwrite parameter is not provided
- **WHEN** `InitExcel` is called without the `overwrite` parameter
- **THEN** method behaves as current implementation (overwrites file)

### Requirement: ExcelService maintains backward compatibility
The ExcelService SHALL maintain existing behavior for all current method signatures and parameters.

#### Scenario: Existing code continues to work without changes
- **WHEN** existing code calls `InitExcel` without the `overwrite` parameter
- **THEN** method behaves identically to current implementation (overwrites file)

#### Scenario: Existing error handling patterns remain valid
- **WHEN** existing code checks the result tuple for success/failure
- **THEN** method returns same tuple structure and error types as current implementation