"""Tests for the plate-validation helpers used by the print_start callback.

Covers the #1204 fix: when two plates of the same model are printed back to
back, MQTT subtask_name can lag and the FTP candidate built from it lands on
the previous plate's still-resident upload. The fix peeks the slice_info
plate index, compares it to the plate parsed from gcode_file, and (on
mismatch) re-fetches with a corrected name.

Pinned here:
- ``peek_plate_index_in_3mf`` reads ONLY ``Metadata/slice_info.config`` and
  returns the integer plate index, or None on any failure (missing entry,
  malformed XML, unreadable zip, etc.). Cheap by design — the full parse
  runs later inside ArchiveService.
- ``swap_plate_suffix`` rewrites the trailing plate number in a Bambu-style
  job name. Covers both the spaced "Project - Plate N" form and the
  underscored "project_plate_N" variant seen in real subtask_names.
"""

import zipfile

import pytest

from backend.app.services.archive import peek_plate_index_in_3mf, swap_plate_suffix


def _make_3mf(tmp_path, *, plate_index: int | None = None, malformed: bool = False):
    """Build a minimal 3MF with a single ``<plate>`` whose ``index`` metadata is set."""
    path = tmp_path / "test.3mf"
    if malformed:
        path.write_bytes(b"not a zip")
        return path
    with zipfile.ZipFile(path, "w") as zf:
        if plate_index is None:
            # plate present but with no index metadata — exercise the "no index" branch
            zf.writestr("Metadata/slice_info.config", "<config><plate></plate></config>")
        else:
            zf.writestr(
                "Metadata/slice_info.config",
                f'<config><plate><metadata key="index" value="{plate_index}" /></plate></config>',
            )
    return path


class TestPeekPlateIndexIn3mf:
    def test_returns_index_for_valid_3mf(self, tmp_path):
        path = _make_3mf(tmp_path, plate_index=2)
        assert peek_plate_index_in_3mf(path) == 2

    def test_returns_none_when_index_missing(self, tmp_path):
        path = _make_3mf(tmp_path, plate_index=None)
        assert peek_plate_index_in_3mf(path) is None

    def test_returns_none_when_slice_info_absent(self, tmp_path):
        path = tmp_path / "noslice.3mf"
        with zipfile.ZipFile(path, "w") as zf:
            zf.writestr("3D/3dmodel.model", "<model/>")
        assert peek_plate_index_in_3mf(path) is None

    def test_returns_none_on_non_zip_file(self, tmp_path):
        path = _make_3mf(tmp_path, malformed=True)
        assert peek_plate_index_in_3mf(path) is None

    def test_returns_none_on_missing_file(self, tmp_path):
        assert peek_plate_index_in_3mf(tmp_path / "does-not-exist.3mf") is None

    def test_returns_none_on_non_integer_index(self, tmp_path):
        path = tmp_path / "bad.3mf"
        with zipfile.ZipFile(path, "w") as zf:
            zf.writestr(
                "Metadata/slice_info.config",
                '<config><plate><metadata key="index" value="abc" /></plate></config>',
            )
        assert peek_plate_index_in_3mf(path) is None


class TestSwapPlateSuffix:
    @pytest.mark.parametrize(
        ("name", "target", "expected"),
        [
            # Bambu Studio's default form (spaces around hyphen, capitalised "Plate").
            ("MyModel - Plate 2", 1, "MyModel - Plate 1"),
            ("MyModel - Plate 1", 5, "MyModel - Plate 5"),
            # Hyphen variants without surrounding spaces should still match (regex
            # uses \s* — slicer output occasionally normalises spacing).
            ("Tight-Plate 3", 7, "Tight-Plate 7"),
            # Underscored form seen in real subtask_names (see
            # test_print_start_expected_promotion fixture "Box3.0_(2)_plate_5").
            ("Box3.0_(2)_plate_5", 1, "Box3.0_(2)_plate_1"),
            # Case-insensitive match — older exports occasionally use lowercase.
            ("model - plate 4", 2, "model - plate 2"),
        ],
    )
    def test_swaps_plate_number(self, name, target, expected):
        assert swap_plate_suffix(name, target) == expected

    @pytest.mark.parametrize(
        "name",
        [
            "JustAModelName",  # No plate suffix at all — single-plate project.
            "Model with - Plate in middle of name",  # "Plate" not at the end.
            "Plate 2",  # Bare "Plate N" with no base — refuse rather than guess.
            "",  # Empty string.
        ],
    )
    def test_returns_none_when_no_recognised_suffix(self, name):
        assert swap_plate_suffix(name, 1) is None

    def test_returns_none_for_none_input(self):
        assert swap_plate_suffix(None, 1) is None

    def test_preserves_separator_casing(self):
        # The replacement must not normalise " - Plate " to "_plate_" or vice versa.
        # Otherwise the corrected name won't match what BambuStudio actually uploaded.
        assert swap_plate_suffix("Model - Plate 1", 2) == "Model - Plate 2"
        assert swap_plate_suffix("model_plate_1", 2) == "model_plate_2"