"""Tests for Phase 3.4 — Knowtation extension of ``muse code index rebuild``.

Verifies that when ``read_domain(root) == "knowtation"`` the rebuild command
also reconstructs the link graph (wikilinks + markdown refs + entity refs)
and surfaces it in the JSON output via the ``knowtation_link_graph_*`` keys.

Test tiers (Rule #0):
1. Unit       — argparse / dispatch shape (the TypedDict extension)
2. Integration — full rebuild on a synthetic vault with mixed link types
3. Stress     — rebuild on a 500-note vault completes well under budget
4. Security   — corrupted note bytes do not crash the rebuild
"""

from __future__ import annotations

import argparse
import io
import json
import pathlib
import types
from contextlib import redirect_stdout

import pytest

from muse.cli.commands import index_rebuild as idx_rebuild_cmd


# ============================================================================
# Helpers
# ============================================================================


def _make_vault(tmp_path: pathlib.Path, files: dict[str, bytes]) -> pathlib.Path:
    for rel, content in files.items():
        full = tmp_path / rel
        full.parent.mkdir(parents=True, exist_ok=True)
        full.write_bytes(content)
    return tmp_path


def _stub_require_repo(monkeypatch: pytest.MonkeyPatch, root: pathlib.Path) -> None:
    """Stub ``require_repo`` to return *root* without checking for ``.muse/``."""
    monkeypatch.setattr(idx_rebuild_cmd, "require_repo", lambda: root)


def _stub_domain(monkeypatch: pytest.MonkeyPatch, domain: str) -> None:
    """Force ``read_domain`` to return *domain* regardless of root."""
    import muse.plugins.registry as registry
    monkeypatch.setattr(registry, "read_domain", lambda _r: domain)


def _stub_symbol_history_build(monkeypatch: pytest.MonkeyPatch) -> None:
    """Stub the Code-domain index builders so we don't need a real Muse repo."""
    monkeypatch.setattr(idx_rebuild_cmd, "_build_symbol_history", lambda _r, **_kw: {})
    monkeypatch.setattr(idx_rebuild_cmd, "_build_hash_occurrence", lambda _r: {})
    monkeypatch.setattr(idx_rebuild_cmd, "save_symbol_history", lambda *_a, **_kw: None)
    monkeypatch.setattr(idx_rebuild_cmd, "save_hash_occurrence", lambda *_a, **_kw: None)

    # Stub SymbolCache so we don't need a real one.
    class _FakeCache:
        def save(self) -> None:
            return None

    monkeypatch.setattr(idx_rebuild_cmd, "load_symbol_cache", lambda _r: _FakeCache())


def _run_rebuild(as_json: bool = True) -> str:
    """Invoke ``run_rebuild`` with a sensible default Namespace."""
    args = argparse.Namespace(
        index_name=None,
        dry_run=True,
        verbose=False,
        as_json=as_json,
    )
    buf = io.StringIO()
    with redirect_stdout(buf):
        idx_rebuild_cmd.run_rebuild(args)
    return buf.getvalue()


# ============================================================================
# TestKnowtationIndexExtension
# ============================================================================


class TestKnowtationIndexExtension:
    def test_link_graph_keys_present_for_knowtation_domain(
        self, tmp_path: pathlib.Path, monkeypatch: pytest.MonkeyPatch
    ) -> None:
        _make_vault(tmp_path, {
            "a.md": b"[[B]] and [c](c.md)",
            "b.md": b"# B",
            "c.md": b"# C",
            "broken.md": b"[[DoesNotExist]]",
        })
        _stub_require_repo(monkeypatch, tmp_path)
        _stub_domain(monkeypatch, "knowtation")
        _stub_symbol_history_build(monkeypatch)

        out = _run_rebuild(as_json=True)
        payload = json.loads(out)

        assert "knowtation_link_graph_notes" in payload
        assert payload["knowtation_link_graph_notes"] == 4
        assert payload["knowtation_link_graph_edges_resolved"] >= 2
        assert payload["knowtation_link_graph_edges_broken"] >= 1
        assert "knowtation_link_graph" in payload["rebuilt"]

    def test_link_graph_keys_absent_for_code_domain(
        self, tmp_path: pathlib.Path, monkeypatch: pytest.MonkeyPatch
    ) -> None:
        _make_vault(tmp_path, {})
        _stub_require_repo(monkeypatch, tmp_path)
        _stub_domain(monkeypatch, "code")
        _stub_symbol_history_build(monkeypatch)

        out = _run_rebuild(as_json=True)
        payload = json.loads(out)

        assert "knowtation_link_graph_notes" not in payload
        assert "knowtation_link_graph" not in payload["rebuilt"]

    def test_entity_index_counted(
        self, tmp_path: pathlib.Path, monkeypatch: pytest.MonkeyPatch
    ) -> None:
        _make_vault(tmp_path, {
            "a.md": b"---\nentity:\n  - Alice\n  - Bob\n---\nA",
            "b.md": b"---\nentity:\n  - Bob\n---\nB",
        })
        _stub_require_repo(monkeypatch, tmp_path)
        _stub_domain(monkeypatch, "knowtation")
        _stub_symbol_history_build(monkeypatch)

        out = _run_rebuild(as_json=True)
        payload = json.loads(out)

        assert payload["knowtation_link_graph_entities"] == 2  # Alice + Bob


# ============================================================================
# TestStress
# ============================================================================


class TestStress:
    def test_500_note_vault_rebuilds_under_5s(
        self, tmp_path: pathlib.Path, monkeypatch: pytest.MonkeyPatch
    ) -> None:
        import time

        files: dict[str, bytes] = {}
        for i in range(500):
            files[f"note_{i:04d}.md"] = (
                f"# Note {i}\n[[note_{(i + 1) % 500:04d}]] "
                f"[neighbour](./note_{(i + 2) % 500:04d}.md)"
            ).encode()
        _make_vault(tmp_path, files)
        _stub_require_repo(monkeypatch, tmp_path)
        _stub_domain(monkeypatch, "knowtation")
        _stub_symbol_history_build(monkeypatch)

        start = time.monotonic()
        out = _run_rebuild(as_json=True)
        elapsed = time.monotonic() - start

        payload = json.loads(out)
        assert payload["knowtation_link_graph_notes"] == 500
        assert elapsed < 5.0, f"500-note rebuild took {elapsed:.2f}s (budget 5s)"


# ============================================================================
# TestSecurity
# ============================================================================


class TestSecurity:
    def test_corrupt_note_bytes_do_not_crash(
        self, tmp_path: pathlib.Path, monkeypatch: pytest.MonkeyPatch
    ) -> None:
        _make_vault(tmp_path, {
            "good.md": b"[[other]]",
            "corrupt.md": bytes(range(256)) * 5,
            "binary.md": b"\x00\x01\x02\x03[[other]]\xff\xfe",
            "other.md": b"# Other",
        })
        _stub_require_repo(monkeypatch, tmp_path)
        _stub_domain(monkeypatch, "knowtation")
        _stub_symbol_history_build(monkeypatch)

        try:
            out = _run_rebuild(as_json=True)
            payload = json.loads(out)
            assert payload["knowtation_link_graph_notes"] == 4
        except Exception as exc:
            pytest.fail(f"Corrupt note bytes crashed rebuild: {exc}")