"""Tests for the XML writer (Excel data -> GX Works3 XML)."""

from __future__ import annotations

from pathlib import Path

from mitsubishi_label_converter.models import (
    GlobalVarSection,
    ProjectMetadata,
    StructMember,
    Variable,
)
from mitsubishi_label_converter.parser import (
    parse_global_vars,
    parse_project_metadata,
)
from mitsubishi_label_converter.xml_writer import write_xml


def make_sections() -> list[GlobalVarSection]:
    return [
        GlobalVarSection(
            name="Global",
            retain=False,
            variables=[
                Variable("Always_ON", "SM400", "BOOL", "", line_number=3),
                Variable("version", "D450", "STRING[12]", ""),
                Variable(
                    "PLC_FEL_STA",
                    "",
                    "ST_Din_STA",
                    "",
                    line_number=39,
                    members=(
                        StructMember("Value", "D0.0"),
                        StructMember("Status", "D1"),
                    ),
                ),
                Variable(
                    "Switch_status",
                    "SD200",
                    "INT",
                    "CPU switch status (0: RUN, 1: STOP)",
                    line_number=14,
                ),
            ],
        ),
        GlobalVarSection(
            name="Global",
            retain=True,
            variables=[
                Variable(
                    "PulseTot", "D600", "WORD", "", line_number=31, retain=True
                ),
            ],
        ),
    ]


def make_metadata() -> ProjectMetadata:
    return ProjectMetadata(
        file_header={
            "companyName": "MITSUBISHI ELECTRIC CORPORATION",
            "companyURL": "http://www.mitsubishielectric.com",
            "productName": "GX Works3",
            "productVersion": "1.126G",
            "creationDateTime": "2026-10-01T20:59:19+02:00",
        },
        content_header={
            "name": "21014JON-B14_20260930",
            "modificationDateTime": "2026-10-01T20:57:58+02:00",
        },
        project_add_data={"projectPlcType": "FX5U"},
    )


def test_full_round_trip(tmp_path: Path) -> None:
    """XML -> sections -> XML: the parsed data must be identical."""
    out = tmp_path / "regenerated.xml"
    sections = make_sections()
    write_xml(sections, make_metadata(), out)

    # The regenerated file must parse back to the same sections.
    reparsed = parse_global_vars(out)
    assert reparsed == sections

    meta = parse_project_metadata(out)
    assert meta.file_header == make_metadata().file_header
    assert meta.content_header == make_metadata().content_header
    assert meta.project_add_data == make_metadata().project_add_data


def test_output_is_utf16_le(tmp_path: Path) -> None:
    out = tmp_path / "regenerated.xml"
    write_xml(make_sections(), make_metadata(), out)
    raw = out.read_bytes()
    # UTF-16 LE BOM
    assert raw[:2] == b"\xff\xfe"
    # XML declaration must declare utf-16
    assert raw.decode("utf-16").startswith('<?xml version="1.0" encoding="utf-16"?>')


def test_retain_flag_written(tmp_path: Path) -> None:
    out = tmp_path / "regenerated.xml"
    write_xml(make_sections(), make_metadata(), out)
    text = out.read_text(encoding="utf-16")
    assert '<globalVars name="Global" retain="true">' in text
    # the plain section: retain attribute must NOT be present
    assert '<globalVars name="Global">' in text


def test_member_addresses_written(tmp_path: Path) -> None:
    out = tmp_path / "regenerated.xml"
    write_xml(make_sections(), make_metadata(), out)
    text = out.read_text(encoding="utf-16")
    assert 'member name="Value" address="D0.0"' in text
    assert 'member name="Status" address="D1"' in text


def test_comment_written(tmp_path: Path) -> None:
    out = tmp_path / "regenerated.xml"
    write_xml(make_sections(), make_metadata(), out)
    reparsed = parse_global_vars(out)
    switch_status = reparsed[0].variables[3]
    assert switch_status.comment == "CPU switch status (0: RUN, 1: STOP)"


def test_line_numbers_written(tmp_path: Path) -> None:
    out = tmp_path / "regenerated.xml"
    write_xml(make_sections(), make_metadata(), out)
    reparsed = parse_global_vars(out)
    assert [v.line_number for v in reparsed[0].variables] == [3, None, 39, 14]


def test_real_file_full_round_trip(tmp_path: Path) -> None:
    """The real asset: XML -> sections -> XML -> sections must be stable."""
    asset = Path(__file__).parents[1] / "assets" / "Global.xml"
    if not asset.is_file():
        import pytest

        pytest.skip("assets/Global.xml not present")

    original_sections = parse_global_vars(asset)
    original_meta = parse_project_metadata(asset)

    out = tmp_path / "regenerated.xml"
    write_xml(original_sections, original_meta, out)

    reparsed_sections = parse_global_vars(out)
    reparsed_meta = parse_project_metadata(out)
    assert reparsed_sections == original_sections
    assert reparsed_meta.file_header == original_meta.file_header
    assert reparsed_meta.content_header == original_meta.content_header
    assert reparsed_meta.project_add_data == original_meta.project_add_data