# tests/test_preview.py
"""Tests for video preview utilities and routes."""

import os
import tempfile

import cv2
import numpy as np
import pytest

from src.preview import probe_video, extract_thumbnail, extract_sample_frames


@pytest.fixture
def sample_video(tmp_path):
    """Create a small test video (10 frames, 25 fps, 320x240)."""
    video_path = str(tmp_path / "test.mp4")
    fourcc = cv2.VideoWriter_fourcc(*"mp4v")
    writer = cv2.VideoWriter(video_path, fourcc, 25.0, (320, 240))
    for i in range(10):
        frame = np.full((240, 320, 3), [(i * 25) % 256, 100, 200], dtype=np.uint8)
        writer.write(frame)
    writer.release()
    return video_path


# --- Unit tests for preview.py ---

def test_probe_video(sample_video, tmp_path):
    info = probe_video(sample_video)
    assert info["width"] == 320
    assert info["height"] == 240
    assert info["fps"] == 25.0
    assert info["frame_count"] == 10
    assert info["duration"] == pytest.approx(0.4, abs=0.05)


def test_probe_video_not_found():
    with pytest.raises(FileNotFoundError):
        probe_video("/nonexistent/video.mp4")


def test_extract_thumbnail(sample_video, tmp_path):
    out = str(tmp_path / "thumb.jpg")
    result = extract_thumbnail(sample_video, out, time_sec=0.1)
    assert result == out
    assert os.path.isfile(out)
    assert os.path.getsize(out) > 0


def test_extract_thumbnail_custom_time(sample_video, tmp_path):
    out = str(tmp_path / "thumb.jpg")
    result = extract_thumbnail(sample_video, out, time_sec=0.0)
    assert os.path.isfile(result)


def test_extract_thumbnail_not_found():
    with pytest.raises(FileNotFoundError):
        extract_thumbnail("/nonexistent/video.mp4", "/tmp/thumb.jpg")


def test_extract_sample_frames(sample_video, tmp_path):
    out_dir = str(tmp_path / "samples")
    paths = extract_sample_frames(sample_video, out_dir, count=3)
    assert len(paths) == 3
    for p in paths:
        assert os.path.isfile(p)
        assert p.endswith(".jpg")


def test_extract_sample_frames_default(sample_video, tmp_path):
    out_dir = str(tmp_path / "samples")
    paths = extract_sample_frames(sample_video, out_dir)
    assert len(paths) == 6


def test_extract_sample_frames_not_found():
    with pytest.raises(FileNotFoundError):
        extract_sample_frames("/nonexistent/video.mp4", "/tmp/samples")


# --- Route tests ---

@pytest.fixture
def client():
    from app import app
    app.config["TESTING"] = True
    with app.test_client() as c:
        yield c


def test_preview_thumb_nonexistent(client):
    resp = client.get("/preview/thumb/nonexistent")
    assert resp.status_code == 404


def test_api_job_samples_nonexistent(client):
    resp = client.get("/api/jobs/nonexistent/samples")
    assert resp.status_code == 404
    data = resp.get_json()
    assert "error" in data


def test_api_job_frame_nonexistent(client):
    resp = client.get("/api/jobs/nonexistent/frame")
    assert resp.status_code == 404


def test_api_job_frame_no_latest_frame(client):
    """Frame route returns 404 when no latest_frame is set (Task 5 TBD)."""
    from app import job_queue
    job = job_queue.add_job(video_path="/tmp/test.mp4", model_configs=[])
    resp = client.get(f"/api/jobs/{job.job_id}/frame")
    assert resp.status_code == 404