"""Unit tests for utils module."""

import pytest

from haproxy_mcp.utils import parse_stat_csv


class TestParseStatCsv:
    """Tests for parse_stat_csv function."""

    def test_parse_valid_csv(self, response_builder):
        """Parse valid HAProxy stat CSV output."""
        csv = response_builder.stat_csv([
            {"pxname": "pool_1", "svname": "pool_1_1", "scur": 5, "status": "UP", "weight": 1, "check_status": "L4OK"},
            {"pxname": "pool_1", "svname": "pool_1_2", "scur": 3, "status": "UP", "weight": 1, "check_status": "L4OK"},
        ])

        results = list(parse_stat_csv(csv))

        assert len(results) == 2
        assert results[0]["pxname"] == "pool_1"
        assert results[0]["svname"] == "pool_1_1"
        assert results[0]["scur"] == "5"
        assert results[0]["status"] == "UP"
        assert results[0]["weight"] == "1"
        assert results[0]["check_status"] == "L4OK"

    def test_parse_empty_output(self):
        """Parse empty output returns no results."""
        results = list(parse_stat_csv(""))
        assert results == []

    def test_parse_header_only(self):
        """Parse output with only header returns no results."""
        csv = "# pxname,svname,qcur,qmax,scur,smax,..."
        results = list(parse_stat_csv(csv))
        assert results == []

    def test_skip_comment_lines(self):
        """Comment lines are skipped."""
        csv = """# This is a comment
# Another comment
pool_1,pool_1_1,0,0,5,10,0,0,0,0,0,0,0,0,0,0,0,UP,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,L4OK,"""

        results = list(parse_stat_csv(csv))
        assert len(results) == 1
        assert results[0]["pxname"] == "pool_1"

    def test_skip_empty_lines(self):
        """Empty lines are skipped."""
        csv = """
pool_1,pool_1_1,0,0,5,10,0,0,0,0,0,0,0,0,0,0,0,UP,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,L4OK,

pool_1,pool_1_2,0,0,3,10,0,0,0,0,0,0,0,0,0,0,0,UP,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,L4OK,
"""

        results = list(parse_stat_csv(csv))
        assert len(results) == 2

    def test_parse_down_status(self, response_builder):
        """Parse server with DOWN status."""
        csv = response_builder.stat_csv([
            {"pxname": "pool_1", "svname": "pool_1_1", "status": "DOWN", "check_status": "L4TOUT"},
        ])

        results = list(parse_stat_csv(csv))

        assert len(results) == 1
        assert results[0]["status"] == "DOWN"
        assert results[0]["check_status"] == "L4TOUT"

    def test_parse_maint_status(self, response_builder):
        """Parse server with MAINT status."""
        csv = response_builder.stat_csv([
            {"pxname": "pool_1", "svname": "pool_1_1", "status": "MAINT"},
        ])

        results = list(parse_stat_csv(csv))

        assert len(results) == 1
        assert results[0]["status"] == "MAINT"

    def test_parse_multiple_backends(self, response_builder):
        """Parse output with multiple backends."""
        csv = response_builder.stat_csv([
            {"pxname": "pool_1", "svname": "pool_1_1", "status": "UP"},
            {"pxname": "pool_2", "svname": "pool_2_1", "status": "UP"},
            {"pxname": "pool_3", "svname": "pool_3_1", "status": "DOWN"},
        ])

        results = list(parse_stat_csv(csv))

        assert len(results) == 3
        assert results[0]["pxname"] == "pool_1"
        assert results[1]["pxname"] == "pool_2"
        assert results[2]["pxname"] == "pool_3"

    def test_parse_frontend_backend_rows(self):
        """Frontend and BACKEND rows are included."""
        csv = """pool_1,FRONTEND,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,UP,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,,
pool_1,pool_1_1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,UP,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,L4OK,
pool_1,BACKEND,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,UP,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,,"""

        results = list(parse_stat_csv(csv))

        # All rows with enough columns are returned
        assert len(results) == 3
        svnames = [r["svname"] for r in results]
        assert "FRONTEND" in svnames
        assert "pool_1_1" in svnames
        assert "BACKEND" in svnames

    def test_parse_insufficient_columns(self):
        """Rows with insufficient columns are skipped."""
        csv = "pool_1,pool_1_1,0,0,5"  # Only 5 columns, need more than 17

        results = list(parse_stat_csv(csv))
        assert results == []

    def test_generator_is_lazy(self, response_builder):
        """Verify parse_stat_csv returns a generator (lazy evaluation)."""
        csv = response_builder.stat_csv([
            {"pxname": "pool_1", "svname": "pool_1_1", "status": "UP"},
        ])

        result = parse_stat_csv(csv)

        # Should return a generator, not a list
        import types
        assert isinstance(result, types.GeneratorType)