"""Agent memory (L6.4, M5.2): one note per fact in the agent's folder, an
index the harness keeps, and a snapshot of it for the transcript."""

from pathlib import Path

import pytest

from nisse_dev.memory import Memory
from nisse_dev.vault import Vault, VaultError, split_frontmatter

FOLDER = "memory/nisse-dev"


@pytest.fixture
def memory(tmp_path: Path) -> Memory:
    return Memory(Vault(tmp_path / "v", {FOLDER: "rw", "notes": "ro"}), FOLDER)


def note(memory: Memory, name: str) -> tuple[dict, str]:
    path = memory._vault.root / FOLDER / f"{name}.md"
    return split_frontmatter(path.read_text())


def test_a_fact_is_a_note_with_its_description_and_provenance(memory: Memory) -> None:
    replaced = memory.remember(
        "prefers-small-prs",
        "The operator prefers  small PRs",
        "Don said PRs over 400 lines are hard to review.\n",
        provenance={"source": "work item x"},
    )
    assert not replaced
    front, body = note(memory, "prefers-small-prs")
    assert front["description"] == "The operator prefers small PRs"
    assert front["provenance"]["source"] == "work item x"
    assert body == "Don said PRs over 400 lines are hard to review.\n"


def test_the_same_name_replaces_and_the_index_follows(memory: Memory) -> None:
    memory.remember("b-fact", "Bee", "b", provenance={})
    memory.remember("a-fact", "Ay", "a", provenance={})
    assert memory.remember("a-fact", "Ay, again", "a2", provenance={})
    index = memory.snapshot().text
    assert index.endswith("- [[a-fact]] — Ay, again\n- [[b-fact]] — Bee")
    memory.forget("a-fact")
    assert "a-fact" not in memory.snapshot().text
    with pytest.raises(VaultError, match="no such note"):
        memory.forget("a-fact")


@pytest.mark.parametrize("name", ["index", "Caps", "../x", "a/b", "", "-x"])
def test_names_are_plain(memory: Memory, name: str) -> None:
    with pytest.raises(VaultError, match="a note's name"):
        memory.remember(name, "d", "f", provenance={})


def test_a_note_needs_a_description_and_a_fact(memory: Memory) -> None:
    with pytest.raises(VaultError, match="description and the fact"):
        memory.remember("x", "  ", "f", provenance={})


def test_the_snapshot_is_hashed_and_made_if_missing(memory: Memory) -> None:
    first = memory.snapshot()
    assert first.path == f"{FOLDER}/index.md"
    assert "Nothing yet." in first.text
    assert memory.snapshot().sha == first.sha  # same index, same hash
    memory.remember("x", "Ex", "f", provenance={})
    assert memory.snapshot().sha != first.sha