from io import BytesIO

import openpyxl
import pandas as pd

from src.backend.utils import xlsx


def test_df_to_xlsx_bytes():
    sheet_names = [f"Sheet{i}" for i in range(3)]
    inputs = [
        (sheet_names[i], pd.DataFrame({"a": [i]})) for i in range(len(sheet_names))
    ]
    output = xlsx.df_to_xlsx_bytes(inputs)
    wb = openpyxl.load_workbook(output)
    assert wb.sheetnames == sheet_names


def test_format_cell_value():
    assert xlsx.format_cell_value("This <x>is</x> a test <b><i><u>xxx</u></i></b>")


def test_format_output_xlsx():
    df = pd.DataFrame([{"a": 1}, {"b": 2}])
    excel = BytesIO()
    df.to_excel(excel, index=False)
    excel.seek(0)
    assert xlsx.format_output_xlsx(excel).startswith(
        b"PK"
    ), "Mismatched XLSX file signature"