import tempfile, os
import numpy as np
import h5py

def test_fuse_creates_output_without_lingbot():
    """When lingbot_poses.npz doesn't exist, fuse creates HDF5 with sources only."""
    from fuse.fuse_trajectory import fuse
    with tempfile.TemporaryDirectory() as tmpdir:
        out_h5 = os.path.join(tmpdir, "traj.h5")
        # Create minimal sparse_fixes.h5
        fixes_h5 = os.path.join(tmpdir, "fixes.h5")
        with h5py.File(fixes_h5, "w") as f:
            grp = f.create_group("usv_gps")
            grp.create_dataset("t_ns",    data=np.array([1000, 2000], dtype=np.int64))
            grp.create_dataset("easting", data=np.array([100.0, 101.0]))
            grp.create_dataset("northing",data=np.array([200.0, 201.0]))
            grp.create_dataset("rtk_status", data=np.array([0, 0], dtype=np.int8))
            grp.attrs["utm_zone"] = "31T"
            grp2 = f.create_group("auv_mcap")
            grp2.create_dataset("t_ns",   data=np.array([1000, 2000], dtype=np.int64))
            grp2.create_dataset("lat",    data=np.array([0.0, 0.0]))
            grp2.create_dataset("lon",    data=np.array([0.0, 0.0]))
            grp2.create_dataset("depth_m",data=np.array([5.0, 6.0]))

        fuse(fixes_h5, "/nonexistent/lingbot.npz", out_h5)
        assert os.path.exists(out_h5)
        with h5py.File(out_h5, "r") as f:
            assert "status" in f.attrs