from System.Drawing import Color


def CellRangeFromDimensions(startCell, width, height):
    """Given a start cell and a width and height, return a cell range."""
    endCell = startCell.Offset(width-1, height-1)
    return CellRange(startCell, endCell)


def FormatCellRangeBorders(cellRange):
    """Given a cell range, format it with borders."""
    cellRange.BorderRight = True
    cellRange.BorderTop = True
    cellRange.Cols[1].BorderLeft = True
    cellRange.Rows[cellRange.MaxRow].BorderBottom = True


def ColorAlternateRows(cellRange, mainColor=Color.CornflowerBlue, alternateColor=None):
    """
    Given a cell range format it with a BackColor on alternate rows. 
    
    By default it sets a BackColor of "CornflowerBlue" on every other row, and the other
    rows have no BackColor set. You can change this by passing in different colours as
    the "mainColor" and "alternateColor" arguments.
    """
    for i in range(1, cellRange.MaxRow + 1):
        thisRow = cellRange.Rows[i]
        if cellRange.HeaderRow is not None and cellRange.HeaderRow.Top == thisRow.Top:
            # Skip header row
            continue

        if i % 2 and alternateColor is not None:
            thisRow.BackColor = alternateColor
        elif not i % 2 and mainColor is not None:
            thisRow.BackColor = mainColor