"""Tests for DTM module."""

import json
import pytest
from pathlib import Path


class TestSMRFPipeline:
    def test_pipeline_json_valid(self):
        """create_smrf_pipeline produces valid JSON with expected stages."""
        from lidar_pipeline.dtm import create_smrf_pipeline
        result = create_smrf_pipeline("/data/input/test.laz", "/data/output/test_ground.las")
        pipeline = json.loads(result)

        assert "pipeline" in pipeline
        stages = pipeline["pipeline"]

        # Should have: reader, range filter (ReturnNumber), SMRF, range filter (Classification), writer
        stage_types = [s.get("type") if isinstance(s, dict) else None for s in stages]

        # First stage is the filename string (reader)
        assert isinstance(stages[0], str)
        assert "test.laz" in stages[0]

        # Must contain SMRF filter
        assert "filters.smrf" in stage_types

        # Must contain ReturnNumber filter
        range_stages = [s for s in stages if isinstance(s, dict) and s.get("type") == "filters.range"]
        assert len(range_stages) >= 1
        # At least one should filter ReturnNumber
        assert any("ReturnNumber" in str(s.get("limits", "")) for s in range_stages)

    def test_pipeline_output_path(self):
        """Pipeline output path is set correctly."""
        from lidar_pipeline.dtm import create_smrf_pipeline
        result = create_smrf_pipeline("/input/a.laz", "/output/a_ground.las")
        pipeline = json.loads(result)
        # Last stage should be writer with correct output path
        writer = [s for s in pipeline["pipeline"] if isinstance(s, dict) and s.get("type") == "writers.las"][0]
        assert writer["filename"] == "/output/a_ground.las"