"""Tests for the BOM CSV emitter."""

import csv
import io
from pathlib import Path

from click.testing import CliRunner

from spice2wireviz.cli import main
from spice2wireviz.emitter.bom_emitter import emit_component_bom, emit_wiring_bom
from spice2wireviz.filter import FilterConfig
from spice2wireviz.mapper.inter_module import map_inter_module
from spice2wireviz.parser.models import (
    ParsedNetlist,
    SpiceComponent,
    SpicePin,
)
from spice2wireviz.parser.netlist import parse_netlist

FIXTURES = Path(__file__).parent / "fixtures"


def _parse_csv(csv_str: str) -> list[dict[str, str]]:
    """Parse a CSV string into a list of dicts."""
    reader = csv.DictReader(io.StringIO(csv_str))
    return list(reader)


class TestComponentBom:
    def test_simple_board_bom(self):
        """Component BOM from simple_board.net has expected connectors."""
        netlist = parse_netlist(FIXTURES / "simple_board.net")
        config = FilterConfig()
        csv_str = emit_component_bom(netlist, config)

        rows = _parse_csv(csv_str)
        assert len(rows) > 0

        # Check CSV is parseable and has expected columns
        assert "Reference" in rows[0]
        assert "Prefix" in rows[0]
        assert "Value" in rows[0]

    def test_bom_respects_filters(self):
        """Filter config limits which components appear in BOM."""
        netlist = parse_netlist(FIXTURES / "multi_board.net")
        # Only include J-prefix components
        config = FilterConfig(include_prefixes=["J"])
        csv_str = emit_component_bom(netlist, config)

        rows = _parse_csv(csv_str)
        for row in rows:
            assert row["Prefix"] == "J"

    def test_bom_includes_subcircuit_boundary_components(self):
        """Components inside .subckt definitions are included."""
        netlist = parse_netlist(FIXTURES / "simple_board.net")
        config = FilterConfig()
        csv_str = emit_component_bom(netlist, config)

        rows = _parse_csv(csv_str)
        subcircuit_refs = [r for r in rows if r["Subcircuit"]]
        assert len(subcircuit_refs) > 0

    def test_bom_includes_instances(self):
        """X* instances appear in BOM with subcircuit name as value."""
        netlist = parse_netlist(FIXTURES / "multi_board.net")
        config = FilterConfig()
        csv_str = emit_component_bom(netlist, config)

        rows = _parse_csv(csv_str)
        x_rows = [r for r in rows if r["Prefix"] == "X"]
        assert len(x_rows) > 0
        # Value column should contain the subcircuit name
        for row in x_rows:
            assert row["Value"]  # not empty

    def test_empty_netlist_produces_header_only(self):
        """An empty netlist produces CSV with just the header."""
        netlist = ParsedNetlist()
        config = FilterConfig()
        csv_str = emit_component_bom(netlist, config)

        rows = _parse_csv(csv_str)
        assert len(rows) == 0

        # But header should exist
        lines = csv_str.strip().split("\n")
        assert len(lines) == 1
        assert "Reference" in lines[0]

    def test_bom_preserves_attributes(self):
        """Component attributes appear in the Attributes column."""
        netlist = ParsedNetlist(
            top_level_components=[
                SpiceComponent(
                    reference="J1", prefix="J", value="DB9", nodes=["A", "B"],
                    pins=[
                        SpicePin(name="A", index=1, net_name="A"),
                        SpicePin(name="B", index=2, net_name="B"),
                    ],
                    attributes={"Footprint": "DSUB-9", "MPN": "DE-9S"},
                ),
            ],
        )
        config = FilterConfig()
        csv_str = emit_component_bom(netlist, config)

        rows = _parse_csv(csv_str)
        assert len(rows) == 1
        assert "Footprint=DSUB-9" in rows[0]["Attributes"]
        assert "MPN=DE-9S" in rows[0]["Attributes"]


class TestWiringBom:
    def test_multi_board_wiring_bom(self):
        """Wiring BOM from mapped multi_board.net has cables."""
        netlist = parse_netlist(FIXTURES / "multi_board.net")
        config = FilterConfig()
        wireviz_dict = map_inter_module(netlist, config)
        csv_str = emit_wiring_bom(wireviz_dict)

        rows = _parse_csv(csv_str)
        assert len(rows) > 0
        assert "Cable" in rows[0]
        assert "Wirecount" in rows[0]
        assert "From" in rows[0]
        assert "To" in rows[0]

    def test_wiring_bom_has_net_labels(self):
        """Cables include net name labels."""
        netlist = parse_netlist(FIXTURES / "multi_board.net")
        config = FilterConfig()
        wireviz_dict = map_inter_module(netlist, config)
        csv_str = emit_wiring_bom(wireviz_dict)

        rows = _parse_csv(csv_str)
        # At least some cables should have net labels
        nets_found = [r for r in rows if r["Nets"]]
        assert len(nets_found) > 0

    def test_wiring_bom_endpoints(self):
        """Each cable connects two endpoints."""
        netlist = parse_netlist(FIXTURES / "multi_board.net")
        config = FilterConfig()
        wireviz_dict = map_inter_module(netlist, config)
        csv_str = emit_wiring_bom(wireviz_dict)

        rows = _parse_csv(csv_str)
        for row in rows:
            assert row["From"]  # not empty
            assert row["To"]  # not empty

    def test_empty_wireviz_produces_header_only(self):
        """An empty wireviz dict produces CSV with just the header."""
        csv_str = emit_wiring_bom({})

        rows = _parse_csv(csv_str)
        assert len(rows) == 0

        lines = csv_str.strip().split("\n")
        assert len(lines) == 1
        assert "Cable" in lines[0]


class TestBomCli:
    """CLI integration for --bom and --bom-wiring flags."""

    def test_bom_flag(self):
        """--bom produces CSV output."""
        runner = CliRunner()
        result = runner.invoke(
            main, [str(FIXTURES / "simple_board.net"), "--bom"]
        )
        assert result.exit_code == 0
        assert "Reference" in result.output
        # Should be CSV, not YAML
        assert "connectors:" not in result.output

    def test_bom_wiring_flag(self):
        """--bom-wiring produces cable CSV."""
        runner = CliRunner()
        result = runner.invoke(
            main,
            [str(FIXTURES / "multi_board.net"), "--bom-wiring"],
        )
        assert result.exit_code == 0
        assert "Cable" in result.output
        assert "Wirecount" in result.output
        # Should be CSV, not YAML
        assert "connectors:" not in result.output

    def test_bom_wiring_with_subcircuit(self):
        """--bom-wiring with -s uses single-module mapping."""
        runner = CliRunner()
        result = runner.invoke(
            main,
            [str(FIXTURES / "simple_board.net"), "-s", "amplifier_board", "--bom-wiring"],
        )
        assert result.exit_code == 0
        assert "Cable" in result.output

    def test_bom_and_bom_wiring_mutually_exclusive(self):
        """--bom and --bom-wiring cannot be used together."""
        runner = CliRunner()
        result = runner.invoke(
            main,
            [str(FIXTURES / "simple_board.net"), "--bom", "--bom-wiring"],
        )
        assert result.exit_code != 0

    def test_bom_to_file(self, tmp_path):
        """--bom with -o writes to file."""
        out = tmp_path / "bom.csv"
        runner = CliRunner()
        result = runner.invoke(
            main, [str(FIXTURES / "simple_board.net"), "--bom", "-o", str(out)]
        )
        assert result.exit_code == 0
        assert out.exists()
        content = out.read_text()
        assert "Reference" in content