"""Tests for the column mapping functionality."""

from __future__ import annotations

import pandas as pd
import sys
from pathlib import Path

# Add meta_files to path
sys.path.insert(0, str(Path(__file__).parent.parent / "meta_files"))
from generate_config import apply_column_mapping, get_canonical_schemas


def test_apply_column_mapping():
    """Test that column mapping correctly renames columns."""
    # Create test DataFrame with instrument-specific column names
    test_df = pd.DataFrame(
        {
            "Old_Time_Sec": [1.0, 2.0, 3.0],
            "Old_Particle_Flags": [0, 1, 0],
            "Other_Column": ["a", "b", "c"],
        }
    )

    # Create mapping from canonical to file column names
    test_mapping = {
        "Time (sec)": "Old_Time_Sec",
        "Particle Flags": "Old_Particle_Flags",
        "Nonexistent Column": "YOUR_COLUMN_NAME_FOR_NONEXISTENT",
        "Missing Column": None,
    }

    result = apply_column_mapping(test_df, test_mapping)

    # Check that columns were renamed correctly
    assert "Time (sec)" in result.columns
    assert "Particle Flags" in result.columns
    assert "Other_Column" in result.columns  # Unmapped columns should remain

    # Check that placeholder and None mappings were ignored
    assert "YOUR_COLUMN_NAME_FOR_NONEXISTENT" not in result.columns
    assert "Nonexistent Column" not in result.columns

    # Check that data was preserved
    assert result["Time (sec)"].tolist() == [1.0, 2.0, 3.0]
    assert result["Particle Flags"].tolist() == [0, 1, 0]


def test_get_canonical_schemas():
    """Test that canonical schemas contain expected columns."""
    schemas = get_canonical_schemas()

    # Check that both PbP and HK canonical schemas exist
    assert "pbp_canonical" in schemas
    assert "hk_canonical" in schemas

    # Check for key columns that should be present
    pbp_canonical = schemas["pbp_canonical"]
    assert "Time (sec)" in pbp_canonical
    assert "Particle Flags" in pbp_canonical
    assert "Incand Mass (fg)" in pbp_canonical

    hk_canonical = schemas["hk_canonical"]
    assert "Time Stamp" in hk_canonical
    assert "Time (sec)" in hk_canonical
    assert "Sample Flow Controller Read (sccm)" in hk_canonical


def test_column_mapping_empty_dataframe():
    """Test column mapping with empty DataFrame."""
    empty_df = pd.DataFrame()
    mapping = {"Time (sec)": "Old_Time_Sec"}

    result = apply_column_mapping(empty_df, mapping)
    assert result.empty


def test_column_mapping_no_mapping():
    """Test column mapping when no mapping is provided."""
    test_df = pd.DataFrame({"col1": [1, 2], "col2": [3, 4]})

    result = apply_column_mapping(test_df, {})

    # Should return original DataFrame unchanged
    pd.testing.assert_frame_equal(result, test_df)


if __name__ == "__main__":
    test_apply_column_mapping()
    test_get_canonical_schemas()
    test_column_mapping_empty_dataframe()
    test_column_mapping_no_mapping()
    print("All tests passed!")