import hashlib

import pytest

from tht.pi_skill_projection import (
    FRAGMENT_ORDER,
    PROJECTION_PATH,
    projection_is_current,
    render_projection,
)

# Approved session-language contract (#35); unrelated workflow fragments stay byte-identical.
BASELINE_SHA256 = "a2e6608e1aa07735ef92d96b3a87fca3bfbe3636754330ff6749178c87a37493"


def test_modular_pi_skill_renders_the_byte_identical_approved_projection():
    rendered = render_projection()

    assert FRAGMENT_ORDER == (
        ("{{EVIDENCE_RUNTIME_SEARCH}}", "evidence/runtime-search.md"),
        ("{{DISAMBIGUATION_OPEN_AMBIGUITY}}", "disambiguation/open-ambiguity.md"),
        ("{{DISAMBIGUATION_INSTRUCTIONS}}", "disambiguation/phase-1.md"),
        ("{{MEMORY_INSTRUCTIONS}}", "memory/phase-2.md"),
        ("{{DISAMBIGUATION_REWRITING_INSTRUCTIONS}}", "disambiguation/phase-3.md"),
        ("{{MEMORY_SOLVED_SEARCH_F4}}", "memory/solved-search-f4.md"),
        ("{{DISAMBIGUATION_SCHEMA_GROUNDING}}", "disambiguation/schema-grounding.md"),
        ("{{EVIDENCE_FORMULA_PROPOSALS}}", "evidence/formula-proposals.md"),
        ("{{MEMORY_SOLVED_SEARCH_F6}}", "memory/solved-search-f6.md"),
        ("{{MEMORY_SOLVED_SEARCH_F7}}", "memory/solved-search-f7.md"),
        ("{{MEMORY_PROMOTION_F8}}", "memory/phase-8-promotion.md"),
        ("{{MEMORY_SOLVED_FINALIZATION}}", "memory/solved-finalization.md"),
    )
    assert rendered == render_projection()
    assert hashlib.sha256(rendered).hexdigest() == BASELINE_SHA256
    assert PROJECTION_PATH.read_bytes() == rendered


def test_projection_check_detects_stale_output(tmp_path):
    stale = tmp_path / "SKILL.md"
    stale.write_bytes(b"stale\n")

    assert projection_is_current(stale) is False


def test_projection_rejects_a_missing_or_repeated_static_placeholder():
    with pytest.raises(ValueError, match="exactly once"):
        render_projection(template=b"{{MEMORY_INSTRUCTIONS}}\n")
    with pytest.raises(ValueError, match="exactly once"):
        render_projection(
            template=(
                b"{{DISAMBIGUATION_INSTRUCTIONS}}\n"
                b"{{MEMORY_INSTRUCTIONS}}\n"
                b"{{MEMORY_INSTRUCTIONS}}\n"
            )
        )