import unittest
from pathlib import Path


ROOT = Path(__file__).resolve().parents[1]
SKILL_PATH = ROOT / ".codex" / "skills" / "fesa-fem-specification" / "SKILL.md"


def read_skill():
    return SKILL_PATH.read_text(encoding="utf-8")


def parse_frontmatter(text):
    lines = text.splitlines()
    if not lines or lines[0] != "---":
        raise AssertionError("SKILL.md must start with YAML frontmatter")

    fields = {}
    for line in lines[1:]:
        if line == "---":
            return fields
        key, sep, value = line.partition(":")
        if not sep:
            raise AssertionError(f"Invalid frontmatter line: {line}")
        fields[key.strip()] = value.strip()

    raise AssertionError("SKILL.md frontmatter must be closed")


class FesaFemSpecificationSkillTests(unittest.TestCase):
    def test_skill_file_exists_with_required_frontmatter(self):
        self.assertTrue(SKILL_PATH.exists(), "fesa-fem-specification SKILL.md is missing")

        fields = parse_frontmatter(read_skill())

        self.assertEqual(set(fields), {"name", "description"})
        self.assertEqual(fields["name"], "fesa-fem-specification")
        self.assertIn("Use when", fields["description"])
        self.assertIn("FESA FEM formulations", fields["description"])
        self.assertIn("numerical review", fields["description"])
        self.assertIn("Abaqus .inp", fields["description"])
        self.assertIn("CSV schemas", fields["description"])
        self.assertIn("implementation-planning handoffs", fields["description"])

    def test_skill_body_defines_workflow_and_inputs(self):
        body = read_skill()

        for required_text in (
            "## Inputs",
            "## Workflow",
            "INPUT CHECK",
            "FORMULATION SPEC",
            "NUMERICAL REVIEW CHECK",
            "I/O CONTRACT",
            "HANDOFF",
            "## Quality Gate",
            "docs/SOLVER_SKILL_DESIGN.md",
            "docs/SOLVER_AGENT_DESIGN.md",
            "AGENTS.md",
            "docs/requirements/<feature-id>.md",
            "docs/research/<feature-id>-research.md",
        ):
            self.assertIn(required_text, body)

    def test_skill_body_defines_formulation_contract(self):
        body = read_skill()

        for required_text in (
            "Strong Form",
            "Weak or Variational Form",
            "Discretization",
            "Kinematics",
            "Element Equations",
            "Mapping and Numerical Integration",
            "Output Recovery",
            "Numerical Risks",
            "partition of unity",
            "Kronecker delta",
            "Jacobian",
            "derivative transform",
        ):
            self.assertIn(required_text, body)

    def test_skill_body_defines_io_contract(self):
        body = read_skill()

        for required_text in (
            "Abaqus Input Scope",
            "Model Data Mapping",
            "History Data Mapping",
            "Internal Model Contract",
            "Output and CSV Schemas",
            "*NODE",
            "*ELEMENT",
            "*MATERIAL",
            "*ELASTIC",
            "*BOUNDARY",
            "*STEP",
            "*OUTPUT",
            "*NODE OUTPUT",
            "*ELEMENT OUTPUT",
            "displacements.csv",
            "reactions.csv",
            "element_forces.csv",
            "stresses.csv",
        ):
            self.assertIn(required_text, body)

    def test_skill_body_enforces_scope_boundaries(self):
        body = read_skill()

        for required_text in (
            "Do not implement C++ code.",
            "Do not design C++ APIs.",
            "Do not implement parsers.",
            "Do not run Abaqus, Nastran, or any reference solver.",
            "Do not generate reference CSVs.",
            "Do not approve release readiness.",
        ):
            self.assertIn(required_text, body)


if __name__ == "__main__":
    unittest.main()