from __future__ import annotations

from pathlib import Path

from core.errors import DriverError
from core.models import Bounds
from device.manager import DeviceManager
from driver.base import Driver
from perception.ocr import OCRBox
from tools.describe_screen import describe_screen

PNG_10X20 = b"\x89PNG\r\n\x1a\n\x00\x00\x00\rIHDR\x00\x00\x00\x0a\x00\x00\x00\x14"


class FakeOCREngine:
    def __init__(self, boxes: list[OCRBox]) -> None:
        self._boxes = boxes

    def extract(self, image: bytes | str | Path) -> list[OCRBox]:
        return self._boxes


class TreeFailingDriver(Driver):
    def connect(self) -> None:
        return None

    def disconnect(self) -> None:
        return None

    def screenshot(self) -> bytes:
        return PNG_10X20

    def tap(self, x: float, y: float) -> None:
        return None

    def long_press(self, x: float, y: float, duration_ms: int = 1200) -> None:
        return None

    def swipe(
        self,
        start_x: float,
        start_y: float,
        end_x: float,
        end_y: float,
        duration_ms: int = 500,
    ) -> None:
        return None

    def input(self, text: str) -> None:
        return None

    def launch(self, app_id: str) -> None:
        return None

    def terminate(self, app_id: str) -> None:
        return None

    def tree(self):
        raise DriverError("ui tree retrieval failed")

    def home(self) -> None:
        return None

    def lock(self) -> None:
        return None

    def unlock(self) -> None:
        return None


def test_describe_screen_degrades_to_ocr_only_when_ui_tree_unavailable() -> None:
    manager = DeviceManager()
    manager.register_device("phone-1", lambda: TreeFailingDriver())
    manager.connect("phone-1")
    fake_box = OCRBox(text="Search", bounds=Bounds(1, 2, 4, 4), confidence=0.9)
    fake_engine = FakeOCREngine([fake_box])

    scene = describe_screen(
        "phone-1",
        manager=manager,
        ocr_engine=fake_engine,  # type: ignore[arg-type]
    )

    assert [element.text for element in scene.elements] == ["Search"]
    assert all(element.source == "ocr" for element in scene.elements)