import json
from dataclasses import asdict
from datetime import datetime, timezone
from pathlib import Path

import pytest
from sqlalchemy import create_engine, func, select
from sqlalchemy.orm import Session

from app.community_importer import CommunityImportError, stage_observations
from app.database import Base
from app.models import DataSource, ExternalObservation
from rf4_research.community_sources import parse_rf4db_catches


FIXTURE = Path(__file__).parents[3] / "tests" / "fixtures" / "rf4db_catches_sample.html"


def record(source: str = "rf4db", external_id: str = "catch-1") -> dict[str, object]:
    return {
        "source_system": source,
        "source_external_id": external_id,
        "source_url": f"https://rf4db.com/ru/catches/{external_id}" if source == "rf4db" else f"https://rf4-stat.ru/fishing/{external_id}",
        "fish": "Щука",
        "fish_external_id": "pike",
        "waterbody": "Тестовое озеро",
        "waterbody_external_id": "test-lake",
        "x": 71,
        "y": 92,
        "weight_g": None,
        "published_at": None,
        "bait": "Приманка",
    }


@pytest.fixture
def db() -> Session:
    engine = create_engine("sqlite://")
    Base.metadata.create_all(engine)
    with Session(engine) as session:
        yield session
    engine.dispose()


def test_staging_is_idempotent_and_preserves_first_seen(db: Session) -> None:
    first = datetime(2026, 9, 3, 10, tzinfo=timezone.utc)
    second = datetime(2026, 9, 3, 11, tzinfo=timezone.utc)

    assert stage_observations(db, [record()], fetched_at=first) == (1, 0)
    changed = record() | {"x": 73, "weight_g": 5_000}
    assert stage_observations(db, [changed], fetched_at=second) == (0, 1)

    item = db.scalar(select(ExternalObservation))
    assert item is not None
    assert (item.x, item.weight_g, item.status) == (73, 5_000, "staged")
    assert item.first_seen_at.replace(tzinfo=timezone.utc) == first
    assert item.last_seen_at.replace(tzinfo=timezone.utc) == second
    assert db.scalar(select(func.count()).select_from(ExternalObservation)) == 1
    source = db.get(DataSource, "rf4db")
    assert source is not None and source.enabled is False


def test_external_ids_are_isolated_by_source(db: Session) -> None:
    created, updated = stage_observations(db, [record("rf4db"), record("rf4stat-fishing")])

    assert (created, updated) == (2, 0)


def test_parser_json_can_be_staged_without_losing_provenance(db: Session) -> None:
    parsed = parse_rf4db_catches(FIXTURE.read_text(encoding="utf-8"))
    payload = json.loads(json.dumps([asdict(item) for item in parsed], default=str))

    assert stage_observations(db, payload) == (1, 0)
    item = db.scalar(select(ExternalObservation))
    assert item is not None
    assert (item.source_system, item.fish_external_id, item.x, item.y) == ("rf4db", "pike", 71, 92)


def test_invalid_source_rolls_back_caller_transaction(db: Session) -> None:
    with pytest.raises(CommunityImportError, match="unsupported source_system"):
        stage_observations(db, [record("unknown")])
    db.rollback()

    assert db.scalar(select(func.count()).select_from(ExternalObservation)) == 0


@pytest.mark.parametrize("change", [
    {"source_url": "https://attacker.example/catch-1"},
    {"x": 10_001},
    {"weight_g": 3_000_001},
])
def test_invalid_provenance_and_ranges_are_rejected(db: Session, change: dict[str, object]) -> None:
    with pytest.raises(CommunityImportError):
        stage_observations(db, [record() | change])
    db.rollback()