"""Unit tests for the HF Dataset sync — fully mocked, no network / huggingface_hub.

Verifies: the local-dev guard (no token => no-op), pull copying the remote file
in, debounced vs forced push, and flush of pending writes.
"""

from __future__ import annotations

import pytest

pytestmark = pytest.mark.unit


class _FakeApi:
    def __init__(self):
        self.uploads = 0
        self.repos = []

    def create_repo(self, **kw):
        self.repos.append(kw.get("repo_id"))

    def upload_file(self, **kw):
        self.uploads += 1


def test_disabled_without_token(tmp_path):
    from src.accounts.hf_sync import HFSync

    s = HFSync(repo_id="user/data", local_db_path=tmp_path / "x.db", token=None)
    assert s.enabled is False
    # Every op is a safe no-op.
    assert s.pull() is False
    assert s.push(force=True) is False
    assert s.flush() is False


def test_disabled_without_repo(tmp_path):
    from src.accounts.hf_sync import HFSync

    s = HFSync(repo_id=None, local_db_path=tmp_path / "x.db", token="tok")
    assert s.enabled is False


def test_pull_copies_remote_file(tmp_path):
    from src.accounts.hf_sync import HFSync

    # Simulate a "remote" file returned by hf_hub_download.
    remote = tmp_path / "remote.db"
    remote.write_bytes(b"SQLITEDATA")
    local = tmp_path / "local" / "accounts.db"

    def fake_downloader(**kw):
        return str(remote)

    s = HFSync(
        repo_id="user/data",
        local_db_path=local,
        token="tok",
        downloader=fake_downloader,
    )
    assert s.enabled is True
    assert s.pull() is True
    assert local.read_bytes() == b"SQLITEDATA"


def test_pull_missing_remote_is_not_error(tmp_path):
    from src.accounts.hf_sync import HFSync

    def boom(**kw):
        raise FileNotFoundError("not there yet")

    s = HFSync(
        repo_id="user/data",
        local_db_path=tmp_path / "a.db",
        token="tok",
        downloader=boom,
    )
    assert s.pull() is False  # fresh deploy: no file yet, handled gracefully


def test_push_debounce_and_force(tmp_path):
    from src.accounts.hf_sync import HFSync

    db = tmp_path / "a.db"
    db.write_bytes(b"data")
    api = _FakeApi()
    s = HFSync(
        repo_id="user/data",
        local_db_path=db,
        token="tok",
        min_push_interval=1000,  # long window so debounce is observable
        api=api,
    )
    assert s.push(force=True) is True  # first forced push succeeds
    assert api.uploads == 1
    assert s.maybe_push() is False  # within debounce window -> skipped, marked pending
    assert api.uploads == 1
    assert s.flush() is True  # pending write gets forced out
    assert api.uploads == 2


def test_ensure_repo(tmp_path):
    from src.accounts.hf_sync import HFSync

    api = _FakeApi()
    s = HFSync(repo_id="user/data", local_db_path=tmp_path / "a.db", token="tok", api=api)
    s.ensure_repo()
    assert "user/data" in api.repos