"""TDD for PiCameraSource (CSI camera via picamera2) — no hardware/picamera2 needed,
by injecting a fake Picamera2 object. Locks the SourcePort contract: read() -> (ok, frame)."""
import numpy as np

from edge.adapters.picamera_source import PiCameraSource


class _FakePicam2:
    def __init__(self, frames):
        self.frames = list(frames)
        self.i = 0
        self.started = False

    def capture_array(self):
        frame = self.frames[self.i % len(self.frames)]
        self.i += 1
        return frame


def test_read_returns_ok_and_frame():
    frame = np.full((480, 640, 3), 128, np.uint8)
    src = PiCameraSource(picam2=_FakePicam2([frame]))
    ok, f = src.read()
    assert ok is True
    assert f.shape == (480, 640, 3)


def test_read_none_frame_returns_false():
    class _Empty:
        def capture_array(self):
            return None

    src = PiCameraSource(picam2=_Empty())
    ok, f = src.read()
    assert ok is False
    assert f is None