"""Unit tests for XER parser."""

from pathlib import Path

import pytest


class TestXerParser:
    """Tests for the XER file parser."""

    def test_parse_single_project_file(self, sample_xer_single_project: Path) -> None:
        """Parser should extract project data from single-project XER file."""
        from xer_mcp.parser.xer_parser import XerParser

        parser = XerParser()
        result = parser.parse(sample_xer_single_project)

        assert len(result.projects) == 1
        assert result.projects[0]["proj_id"] == "1001"
        assert result.projects[0]["proj_short_name"] == "Test Project"

    def test_parse_multi_project_file(self, sample_xer_multi_project: Path) -> None:
        """Parser should extract all projects from multi-project XER file."""
        from xer_mcp.parser.xer_parser import XerParser

        parser = XerParser()
        result = parser.parse(sample_xer_multi_project)

        assert len(result.projects) == 2
        project_names = {p["proj_short_name"] for p in result.projects}
        assert project_names == {"Project Alpha", "Project Beta"}

    def test_parse_activities(self, sample_xer_single_project: Path) -> None:
        """Parser should extract activities from XER file."""
        from xer_mcp.parser.xer_parser import XerParser

        parser = XerParser()
        result = parser.parse(sample_xer_single_project)

        # Single project fixture has 5 activities
        assert len(result.tasks) == 5

        # Check first milestone
        milestone = next(t for t in result.tasks if t["task_code"] == "A1000")
        assert milestone["task_name"] == "Project Start"
        assert milestone["task_type"] == "TT_Mile"

    def test_parse_relationships(self, sample_xer_single_project: Path) -> None:
        """Parser should extract relationships from XER file."""
        from xer_mcp.parser.xer_parser import XerParser

        parser = XerParser()
        result = parser.parse(sample_xer_single_project)

        # Single project fixture has 5 relationships
        assert len(result.taskpreds) == 5

        # Check a FS relationship
        fs_rel = next(r for r in result.taskpreds if r["pred_type"] == "PR_FS")
        assert fs_rel["lag_hr_cnt"] == 0

        # Check a SS relationship
        ss_rel = next(r for r in result.taskpreds if r["pred_type"] == "PR_SS")
        assert ss_rel["lag_hr_cnt"] == 40

    def test_parse_wbs(self, sample_xer_single_project: Path) -> None:
        """Parser should extract WBS hierarchy from XER file."""
        from xer_mcp.parser.xer_parser import XerParser

        parser = XerParser()
        result = parser.parse(sample_xer_single_project)

        # Single project fixture has 3 WBS elements
        assert len(result.projwbs) == 3

        # Check root WBS
        root = next(w for w in result.projwbs if w["wbs_short_name"] == "ROOT")
        assert root["parent_wbs_id"] is None or root["parent_wbs_id"] == ""

    def test_parse_calendars(self, sample_xer_single_project: Path) -> None:
        """Parser should extract calendars from XER file."""
        from xer_mcp.parser.xer_parser import XerParser

        parser = XerParser()
        result = parser.parse(sample_xer_single_project)

        # Single project fixture has 1 calendar
        assert len(result.calendars) == 1
        cal = result.calendars[0]
        assert cal["clndr_name"] == "Standard 5 Day"
        assert cal["day_hr_cnt"] == 8

    def test_parse_empty_project(self, sample_xer_empty: Path) -> None:
        """Parser should handle XER file with no activities."""
        from xer_mcp.parser.xer_parser import XerParser

        parser = XerParser()
        result = parser.parse(sample_xer_empty)

        assert len(result.projects) == 1
        assert len(result.tasks) == 0
        assert len(result.taskpreds) == 0

    def test_parse_invalid_file_raises_error(self, invalid_xer_file: Path) -> None:
        """Parser should raise ParseError for invalid XER content."""
        from xer_mcp.errors import ParseError
        from xer_mcp.parser.xer_parser import XerParser

        parser = XerParser()
        with pytest.raises(ParseError):
            parser.parse(invalid_xer_file)

    def test_parse_nonexistent_file_raises_error(self, nonexistent_xer_path: Path) -> None:
        """Parser should raise FileNotFoundError for missing file."""
        from xer_mcp.errors import FileNotFoundError
        from xer_mcp.parser.xer_parser import XerParser

        parser = XerParser()
        with pytest.raises(FileNotFoundError):
            parser.parse(nonexistent_xer_path)

    def test_parse_dates_converted_to_iso8601(self, sample_xer_single_project: Path) -> None:
        """Parser should convert XER dates to ISO8601 format."""
        from xer_mcp.parser.xer_parser import XerParser

        parser = XerParser()
        result = parser.parse(sample_xer_single_project)

        # Check date conversion (XER: "2026-01-01 07:00" -> ISO: "2026-01-01T07:00:00")
        task = next(t for t in result.tasks if t["task_code"] == "A1000")
        assert "T" in task["target_start_date"]

    def test_parse_driving_path_flag(self, sample_xer_single_project: Path) -> None:
        """Parser should correctly parse driving_path_flag as boolean."""
        from xer_mcp.parser.xer_parser import XerParser

        parser = XerParser()
        result = parser.parse(sample_xer_single_project)

        # A1000 has driving_path_flag = Y
        critical_task = next(t for t in result.tasks if t["task_code"] == "A1000")
        assert critical_task["driving_path_flag"] is True

        # A1020 has driving_path_flag = N
        non_critical = next(t for t in result.tasks if t["task_code"] == "A1020")
        assert non_critical["driving_path_flag"] is False