"""Regression tests for the bug where translated Excel chart <c:f> references
kept pointing at the original (now-renamed) sheet name, causing the chart
to render as zero/empty series after translation.

This is a real bug: see e.g. test_excel.xlsx where the chart references
'Sales 2024'!$D$2:$D$61 but the sheet is renamed to "Chiffre d'affaires
par produit" — the chart then shows 0 for every data point.
"""
import sys
from pathlib import Path

sys.path.insert(0, str(Path(__file__).resolve().parents[1]))

from lxml import etree

from translators.excel_translator import ExcelTranslator

NS_C = "http://schemas.openxmlformats.org/drawingml/2006/chart"


def _build_chart_xml(series_refs):
    """Helper: build a chart XML with the given <c:f> strings."""
    sers = "\n".join(
        f"<c:ser><c:tx><c:strRef><c:f>{ref}</c:f></c:strRef></c:tx>"
        f"<c:cat><c:strRef><c:f>{ref}</c:f></c:strRef></c:cat>"
        f"<c:val><c:numRef><c:f>{ref}</c:f></c:numRef></c:val></c:ser>"
        for ref in series_refs
    )
    return f"""<c:chartSpace xmlns:c="{NS_C}" xmlns:a="http://schemas.openxmlformats.org/drawingml/2006/main">
    <c:chart>
        <c:plotArea><c:lineChart>{sers}</c:lineChart></c:plotArea>
    </c:chart>
</c:chartSpace>"""


def test_quoted_sheet_name_with_apostrophe_in_new_name():
    r = ExcelTranslator._rewrite_sheet_ref(
        "'Sales 2024'!$D$2:$D$61",
        {"Sales 2024": "Chiffre d'affaires par produit"},
    )
    assert r == "'Chiffre d''affaires par produit'!$D$2:$D$61", f"got: {r!r}"


def test_unquoted_sheet_name_simple():
    r = ExcelTranslator._rewrite_sheet_ref(
        "Sheet1!$A$1",
        {"Sheet1": "Feuille1"},
    )
    assert r == "Feuille1!$A$1", f"got: {r!r}"


def test_new_name_with_space_gets_quoted():
    r = ExcelTranslator._rewrite_sheet_ref(
        "Sheet1!$A$1",
        {"Sheet1": "Ma Feuille"},
    )
    assert r == "'Ma Feuille'!$A$1", f"got: {r!r}"


def test_name_not_in_mapping_unchanged():
    r = ExcelTranslator._rewrite_sheet_ref(
        "Other!$A$1",
        {"Sheet1": "Feuille1"},
    )
    assert r == "Other!$A$1", f"got: {r!r}"


def test_empty_mapping_is_noop():
    r = ExcelTranslator._rewrite_sheet_ref("Sheet1!$A$1", {})
    assert r == "Sheet1!$A$1", f"got: {r!r}"


def test_no_bang_is_noop():
    r = ExcelTranslator._rewrite_sheet_ref("just_a_label", {"x": "y"})
    assert r == "just_a_label", f"got: {r!r}"


def test_real_chart_xml_all_refs_rewritten():
    chart_xml = etree.fromstring(_build_chart_xml(["Sheet1!$B$1"]))
    n = ExcelTranslator._rewrite_sheet_refs_in_chart(chart_xml, {"Sheet1": "Ma Feuille"})
    assert n == 3, f"expected 3 rewrites, got {n}"
    refs = [f.text for f in chart_xml.iter(f"{{{NS_C}}}f")]
    assert refs == [
        "'Ma Feuille'!$B$1",
        "'Ma Feuille'!$B$1",
        "'Ma Feuille'!$B$1",
    ], f"got: {refs}"


def test_real_chart_xml_apostrophe_escaped_in_new_name():
    chart_xml = etree.fromstring(_build_chart_xml(["Sheet1!$B$1"]))
    n = ExcelTranslator._rewrite_sheet_refs_in_chart(
        chart_xml, {"Sheet1": "Chiffre d'affaires"}
    )
    assert n == 3
    refs = [f.text for f in chart_xml.iter(f"{{{NS_C}}}f")]
    assert all(r == "'Chiffre d''affaires'!$B$1" for r in refs), f"got: {refs}"


def test_partial_mapping_leaves_other_refs_intact():
    """When only one sheet is renamed, refs to other sheets must stay."""
    chart_xml = etree.fromstring(
        _build_chart_xml(["Sheet1!$A$1", "Sheet2!$B$1"])
    )
    n = ExcelTranslator._rewrite_sheet_refs_in_chart(
        chart_xml, {"Sheet1": "Feuille1"}
    )
    # 3 refs to Sheet1 (one series) are rewritten; 3 refs to Sheet2 stay.
    assert n == 3, f"expected 3 rewrites, got {n}"
    refs = [f.text for f in chart_xml.iter(f"{{{NS_C}}}f")]
    assert "Feuille1!$A$1" in refs
    assert "Sheet2!$B$1" in refs


def test_multiple_series_renamed():
    """When several sheets are renamed, refs to any of them get updated."""
    chart_xml = etree.fromstring(
        _build_chart_xml(["Sheet1!$A$1", "Sheet2!$B$1", "Sheet3!$C$1"])
    )
    n = ExcelTranslator._rewrite_sheet_refs_in_chart(
        chart_xml,
        {"Sheet1": "F1", "Sheet2": "F2", "Sheet3": "F3"},
    )
    assert n == 9, f"expected 9 rewrites (3 series x 3 refs each), got {n}"


if __name__ == "__main__":
    test_quoted_sheet_name_with_apostrophe_in_new_name()
    test_unquoted_sheet_name_simple()
    test_new_name_with_space_gets_quoted()
    test_name_not_in_mapping_unchanged()
    test_empty_mapping_is_noop()
    test_no_bang_is_noop()
    test_real_chart_xml_all_refs_rewritten()
    test_real_chart_xml_apostrophe_escaped_in_new_name()
    test_partial_mapping_leaves_other_refs_intact()
    test_multiple_series_renamed()
    print("All chart sheet-ref rewrite tests passed.")