"""Tests for the PLCopen XML parser."""

from __future__ import annotations

from pathlib import Path

import pytest

from mitsubishi_label_converter.parser import (
    parse_global_vars,
    parse_project_metadata,
)

NS = "http://www.plcopen.org/xml/tc6_0201"

SAMPLE_XML = f"""<?xml version="1.0" encoding="utf-16"?>
<project xmlns="{NS}">
  <instances>
    <configurations>
      <configuration name="">
        <globalVars name="Global">
          <variable name="Always_ON" address="SM400">
            <type><BOOL/></type>
            <addData>
              <data name="http://www.mitsubishielectric.com/xml/variableLineNumber"
                    handleUnknown="implementation">
                <variableLineNumber number="3"/>
              </data>
            </addData>
          </variable>
          <variable name="version" address="D450">
            <type><string length="12"/></type>
          </variable>
          <variable name="PLC_FEL">
            <type><derived name="FB_Din"/></type>
            <addData>
              <data name="http://www.mitsubishielectric.com/xml/variableComments"
                    handleUnknown="implementation">
                <variableComments>
                  <comment number="1">
                    <html xml:space="preserve"
                          xmlns="http://www.w3.org/1999/xhtml">PLC error active</html>
                  </comment>
                </variableComments>
              </data>
            </addData>
          </variable>
          <variable name="PLC_FEL_STA">
            <type><derived name="ST_Din_STA"/></type>
            <addData>
              <data name="http://www.mitsubishielectric.com/xml/variableStructDeviceAssignment"
                    handleUnknown="implementation">
                <variableStructDeviceAssignment>
                  <member name="Value" address="D0.0"/>
                  <member name="Status" address="D1"/>
                </variableStructDeviceAssignment>
              </data>
            </addData>
          </variable>
        </globalVars>
        <globalVars name="Global" retain="true">
          <variable name="PulseTot" address="D600">
            <type><WORD/></type>
          </variable>
        </globalVars>
      </configuration>
    </configurations>
  </instances>
</project>
"""


@pytest.fixture()
def sample_file(tmp_path: Path) -> Path:
    """Write the sample XML as UTF-16 LE, like GX Works3 does."""
    xml_path = tmp_path / "Global.xml"
    xml_path.write_bytes(SAMPLE_XML.encode("utf-16"))
    return xml_path


def test_parses_two_sections(sample_file: Path) -> None:
    sections = parse_global_vars(sample_file)
    assert len(sections) == 2
    assert all(section.name == "Global" for section in sections)


def test_retain_flag_is_parsed(sample_file: Path) -> None:
    sections = parse_global_vars(sample_file)
    assert sections[0].retain is False
    assert sections[1].retain is True


def test_primitive_type(sample_file: Path) -> None:
    sections = parse_global_vars(sample_file)
    first = sections[0].variables[0]
    assert first.name == "Always_ON"
    assert first.address == "SM400"
    assert first.type_name == "BOOL"
    assert first.comment == ""


def test_string_type_includes_length(sample_file: Path) -> None:
    sections = parse_global_vars(sample_file)
    version = sections[0].variables[1]
    assert version.name == "version"
    assert version.type_name == "STRING[12]"


def test_derived_type_uses_name(sample_file: Path) -> None:
    sections = parse_global_vars(sample_file)
    plc_fel = sections[0].variables[2]
    assert plc_fel.address == ""  # derived FB variable without device address
    assert plc_fel.type_name == "FB_Din"
    sta = sections[0].variables[3]
    assert sta.type_name == "ST_Din_STA"
    assert [(m.name, m.address) for m in sta.members] == [
        ("Value", "D0.0"),
        ("Status", "D1"),
    ]


def test_comment_extraction(sample_file: Path) -> None:
    sections = parse_global_vars(sample_file)
    plc_fel = sections[0].variables[2]
    assert plc_fel.comment == "PLC error active"


def test_struct_members_are_parsed(sample_file: Path) -> None:
    sections = parse_global_vars(sample_file)
    # PLC_FEL (plain derived FB) has no member assignments
    assert sections[0].variables[2].members == ()


def test_struct_members_from_real_file() -> None:
    asset = Path(__file__).parents[1] / "assets" / "Global.xml"
    if not asset.is_file():
        pytest.skip("assets/Global.xml not present")
    sections = parse_global_vars(asset)
    structured = [v for s in sections for v in s.variables if v.members]
    assert len(structured) == 189
    sta = next(v for v in structured if v.name == "PLC_FEL_STA")
    assert sta.type_name == "ST_Din_STA"
    assert sta.line_number == 39
    assert (sta.members[0].name, sta.members[0].address) == ("Value", "D0.0")


def test_project_metadata_from_real_file() -> None:
    asset = Path(__file__).parents[1] / "assets" / "Global.xml"
    if not asset.is_file():
        pytest.skip("assets/Global.xml not present")
    meta = parse_project_metadata(asset)
    assert meta.file_header["productName"] == "GX Works3"
    assert meta.content_header["name"] == "21014JON-B14_20260930"
    assert meta.project_add_data["projectPlcType"] == "FX5U"


def test_line_number_is_parsed(sample_file: Path) -> None:
    sections = parse_global_vars(sample_file)
    always_on = sections[0].variables[0]
    assert always_on.line_number == 3


def test_real_world_global_xml() -> None:
    """End-to-end check against the real asset in the repository."""
    asset = Path(__file__).parents[1] / "assets" / "Global.xml"
    if not asset.is_file():
        pytest.skip("assets/Global.xml not present")
    sections = parse_global_vars(asset)
    assert len(sections) == 2
    # 174/118 raw child elements include one <addData> (varListProperties) each
    assert [len(s.variables) for s in sections] == [173, 117]
    version_row = sections[0].variables[0]
    assert version_row.name == "version"
    assert version_row.address == "D450"
    assert version_row.type_name == "STRING[12]"