"""Tests for ``src/seed_local_dispatch_energy.py``.

Covers:
- ``derive_token_prices`` on synthetic samples with ground truth
- No-tariff refusal (exit 1, message)
- ``--dry-run`` makes zero HTTP calls and zero DB writes
- Write path updates the temp-DB models row exactly
"""

from __future__ import annotations

import sqlite3
import sys
from pathlib import Path
from unittest.mock import MagicMock, patch

import pytest
import yaml

TEST_DIR = Path(__file__).resolve().parent
ROOT = TEST_DIR.parent
SRC = ROOT / "src"

sys.path.insert(0, str(SRC))

from seed_local_dispatch_core import derive_token_prices
from seed_local_dispatch_energy import _is_loopback


class TestDeriveTokenPrices:
    def test_recover_ground_truth(self):
        tariff = 8.0
        true_a = 1e-7
        true_b = 5e-7
        expected_prompt = tariff * true_a * 1e6
        expected_completion = tariff * true_b * 1e6

        samples = [(p, c, true_a * p + true_b * c)
                   for p in (100, 250, 500, 800, 1000)
                   for c in (50, 150, 300, 600, 1200)]

        cost_p, cost_c, stats = derive_token_prices(samples, tariff)

        assert cost_p == pytest.approx(expected_prompt, rel=1e-6)
        assert cost_c == pytest.approx(expected_completion, rel=1e-6)
        assert stats["r_squared"] == pytest.approx(1.0, abs=1e-10)
        assert stats["slope_prompt"] == pytest.approx(true_a, rel=1e-6)
        assert stats["slope_completion"] == pytest.approx(true_b, rel=1e-6)

    def test_r_squared_near_one_with_noise(self):
        tariff = 8.0
        samples = []
        noise = 1e-9
        for p in (100, 500, 1000, 2000):
            for c in (50, 200, 500):
                energy = 1e-7 * p + 5e-7 * c + noise
                samples.append((p, c, energy))

        _, _, stats = derive_token_prices(samples, tariff)
        assert stats["r_squared"] > 0.99

    def test_asymmetric_slopes(self):
        tariff = 0.12
        samples = [(1000, 100, 0.0012), (500, 500, 0.0036), (200, 1000, 0.0060)]
        cost_p, cost_c, _ = derive_token_prices(samples, tariff)
        assert cost_c > cost_p

    def test_single_sample_raises(self):
        with pytest.raises(ValueError, match="need at least 2 samples"):
            derive_token_prices([(100, 50, 0.001)], 8.0)

    def test_empty_raises(self):
        with pytest.raises(ValueError, match="need at least 2 samples"):
            derive_token_prices([], 8.0)

    def test_stats_contain_n_samples(self):
        samples = [(100, 50, 0.0001), (200, 200, 0.0002)]
        _, _, stats = derive_token_prices(samples, 8.0)
        assert stats["n_samples"] == 2
        assert "slope_prompt" in stats
        assert "slope_completion" in stats
        assert "r_squared" in stats
        assert "median_prompt_tokens" in stats
        assert "median_completion_tokens" in stats


class TestIsLoopback:
    def test_localhost(self):
        assert _is_loopback("http://localhost:11434/v1")
        assert _is_loopback("http://localhost:11434")

    def test_127_0_0_1(self):
        assert _is_loopback("http://127.0.0.1:8080/v1")

    def test_non_loopback(self):
        assert not _is_loopback("http://10.0.0.5:11434")
        assert not _is_loopback("https://api.example.com/v1")

    def test_trailing_path_after_v1(self):
        assert _is_loopback("http://127.0.0.1:11434/v1/test")


def _entry(model_id: str, base_url: str):
    return MagicMock(model_id=model_id, base_url=base_url)


class TestCliRefusal:
    def test_tariff_none_refuses(self, tmp_path, capsys):
        db_path = tmp_path / "test.db"
        _init_db(db_path)
        _seed_local_model(db_path, "test-model")

        import seed_local_dispatch_energy as mod

        mock_cfg = MagicMock()
        mock_cfg.local_energy.enabled = True
        mock_cfg.local_energy.tariff_usd_per_kwh = None
        mock_cfg.local_energy.sample_interval_seconds = 0.25
        mock_cfg.local_energy.meter = "nvidia_smi"
        mock_cfg.local_energy_dispatch_models = frozenset({"test-model"})
        mock_cfg.database.path = str(db_path)
        mock_cfg.local_dispatch_models = [
            _entry("test-model", "http://localhost:11434/v1")
        ]

        with patch.object(mod, "load_config", return_value=mock_cfg), patch.object(
            sys, "argv", ["seed_local_dispatch_energy.py"]
        ):
            result = mod.main()

        assert result == 1
        captured = capsys.readouterr()
        assert "tariff" in captured.err.lower()

    def test_local_energy_disabled_refuses(self, tmp_path, capsys):
        db_path = tmp_path / "x.db"
        _init_db(db_path)
        _seed_local_model(db_path, "test-model")

        import seed_local_dispatch_energy as mod

        mock_cfg = MagicMock()
        mock_cfg.local_energy.enabled = False
        mock_cfg.local_energy.tariff_usd_per_kwh = 8.0
        mock_cfg.local_energy.sample_interval_seconds = 0.25
        mock_cfg.local_energy.meter = "nvidia_smi"
        mock_cfg.local_energy_dispatch_models = frozenset({"test-model"})
        mock_cfg.database.path = str(db_path)
        mock_cfg.local_dispatch_models = [
            _entry("test-model", "http://localhost:11434/v1")
        ]

        with patch.object(mod, "load_config", return_value=mock_cfg), patch.object(
            sys, "argv", ["seed_local_dispatch_energy.py"]
        ):
            result = mod.main()
        assert result == 1
        captured = capsys.readouterr()
        assert "enabled" in captured.err.lower()


class TestLoopbackRefusal:
    def test_non_loopback_models_refuse(self, tmp_path, capsys):
        db_path = tmp_path / "x.db"
        _init_db(db_path)
        _seed_local_model(db_path, "remote-model")

        import seed_local_dispatch_energy as mod

        mock_cfg = MagicMock()
        mock_cfg.local_energy.enabled = True
        mock_cfg.local_energy.tariff_usd_per_kwh = 8.0
        mock_cfg.local_energy.sample_interval_seconds = 0.25
        mock_cfg.local_energy.meter = "nvidia_smi"
        mock_cfg.local_energy_dispatch_models = frozenset({"remote-model"})
        mock_cfg.database.path = str(db_path)
        mock_cfg.local_dispatch_models = [
            _entry("remote-model", "http://10.0.0.5:11434/v1")
        ]

        with patch.object(mod.sqlite3, "connect") as mock_connect, patch.object(
            mod, "load_config", return_value=mock_cfg
        ), patch.object(sys, "argv", ["seed_local_dispatch_energy.py"]):
            mock_conn = MagicMock()
            mock_conn.execute.return_value.fetchall.return_value = [
                {"model_id": "remote-model"}
            ]
            mock_connect.return_value = mock_conn
            result = mod.main()
        assert result == 1
        captured = capsys.readouterr()
        assert "loopback" in captured.err.lower()


class TestDryRun:
    def test_dry_run_zero_http_calls(self, tmp_path, capsys):
        import seed_local_dispatch_energy as mod

        db_path = tmp_path / "dry.db"
        _init_db(db_path)
        _seed_local_model(db_path, "dry-model")

        mock_cfg = MagicMock()
        mock_cfg.local_energy.enabled = True
        mock_cfg.local_energy.tariff_usd_per_kwh = 8.0
        mock_cfg.local_energy.sample_interval_seconds = 0.25
        mock_cfg.local_energy.meter = "nvidia_smi"
        mock_cfg.local_energy_dispatch_models = frozenset({"dry-model"})
        mock_cfg.database.path = str(db_path)
        mock_cfg.local_dispatch_models = [
            _entry("dry-model", "http://localhost:11434/v1")
        ]

        mock_conn = MagicMock()
        mock_conn.execute.return_value.fetchall.return_value = [
            {"model_id": "dry-model"}
        ]
        mock_conn.row_factory = None

        with patch.object(mod.sqlite3, "connect", return_value=mock_conn), patch.object(
            mod, "load_config", return_value=mock_cfg
        ), patch.object(sys, "argv", ["seed_local_dispatch_energy.py", "--dry-run"]):
            result = mod.main()

        assert result == 0
        captured = capsys.readouterr()
        assert "sum_small" in captured.out
        assert "dry-model" in captured.out
        assert not mock_conn.commit.called

    def test_dry_run_zero_db_writes(self, tmp_path):
        import seed_local_dispatch_energy as mod

        db_path = tmp_path / "dry2.db"
        _init_db(db_path)
        _seed_local_model(db_path, "dry-model2")

        mock_cfg = MagicMock()
        mock_cfg.local_energy.enabled = True
        mock_cfg.local_energy.tariff_usd_per_kwh = 8.0
        mock_cfg.local_energy.sample_interval_seconds = 0.25
        mock_cfg.local_energy.meter = "nvidia_smi"
        mock_cfg.local_energy_dispatch_models = frozenset({"dry-model2"})
        mock_cfg.database.path = str(db_path)
        mock_cfg.local_dispatch_models = [
            _entry("dry-model2", "http://localhost:11434/v1")
        ]

        mock_conn = MagicMock(spec=sqlite3.Connection)
        mock_conn.execute.return_value.fetchall.return_value = [
            {"model_id": "dry-model2"}
        ]
        mock_conn.row_factory = None

        with patch.object(mod.sqlite3, "connect", return_value=mock_conn), patch.object(
            mod, "load_config", return_value=mock_cfg
        ), patch.object(sys, "argv", ["seed_local_dispatch_energy.py", "--dry-run"]):
            mod.main()

        assert not mock_conn.commit.called
        updates = 0
        for call in mock_conn.execute.call_args_list:
            stmt = call[0][0] if call[0] else ""
            if stmt.strip().startswith("UPDATE"):
                updates += 1
        assert updates == 0


class TestWritePath:
    def test_write_path_updates_models(self, tmp_path):
        db_path = tmp_path / "write.db"
        _init_db(db_path)
        _seed_local_model(db_path, "write-model")

        tariff = 8.0
        true_a, true_b = 1e-7, 5e-7
        samples_data = [
            {"shape": name, "sample": i + 1, "prompt_tokens": p,
             "completion_tokens": c, "gross_kwh": true_a * p + true_b * c,
             "avg_watts": 50.0, "duration_s": 1.0}
            for name in ("sum_small", "sum_large", "diff_small", "long_answer")
            for i, (p, c) in enumerate([
                (100, 50), (200, 100), (1000, 500), (500, 250), (300, 300)
            ])
        ]

        mock_cfg = MagicMock()
        mock_cfg.local_energy.enabled = True
        mock_cfg.local_energy.tariff_usd_per_kwh = tariff
        mock_cfg.local_energy.sample_interval_seconds = 0.25
        mock_cfg.local_energy.meter = "nvidia_smi"
        mock_cfg.local_energy_dispatch_models = frozenset({"write-model"})
        mock_cfg.database.path = str(db_path)
        mock_cfg.local_dispatch_models = [
            _entry("write-model", "http://localhost:11434/v1")
        ]

        mock_conn = MagicMock()
        mock_conn.execute.return_value.fetchall.return_value = [
            {"model_id": "write-model"}
        ]
        mock_conn.row_factory = None
        mock_conn.commit = MagicMock()

        call_idx = [0]

        def fake_post(url, headers=None, json=None, timeout=None):
            call_idx[0] += 1
            resp = MagicMock()
            resp.raise_for_status = MagicMock()
            sample = samples_data[call_idx[0] - 1]
            resp.json.return_value = {
                "usage": {
                    "prompt_tokens": sample["prompt_tokens"],
                    "completion_tokens": sample["completion_tokens"],
                }
            }
            return resp

        import seed_local_dispatch_energy as mod

        with patch.object(mod.sqlite3, "connect", return_value=mock_conn), patch.object(
            mod, "load_config", return_value=mock_cfg
        ), patch.object(mod, "measure") as mock_measure, patch.object(
            mod.requests, "post", side_effect=fake_post
        ), patch.object(
            sys, "argv", ["seed_local_dispatch_energy.py"]
        ):
            ctx = MagicMock()
            ctx.avg_power_watts = 50.0
            ctx.duration_seconds = 1.0
            mock_measure.return_value.__enter__ = MagicMock(return_value=ctx)
            mock_measure.return_value.__exit__ = MagicMock(return_value=False)

            result = mod.main()

        assert result == 0

        update_count = sum(
            1 for call in mock_conn.execute.call_args_list
            if call[0][0].strip().startswith("UPDATE")
        )
        assert update_count >= 1

        found_model = False
        for call in mock_conn.execute.call_args_list:
            stmt = call[0][0] if call[0] else ""
            if stmt.strip().startswith("UPDATE models SET"):
                params = call[0][1]
                assert len(params) == 3
                assert params[2] == "write-model"
                found_model = True
                assert isinstance(params[0], float)
                assert isinstance(params[1], float)

        assert found_model
        assert mock_conn.commit.called


def _make_config(local_energy_enabled=False, tariff=None):
    raw = yaml.safe_load((ROOT / "config" / "config.yaml").read_text())
    raw["dispatch_providers"] = {}
    raw["local_energy"]["enabled"] = local_energy_enabled
    raw["local_energy"]["tariff_usd_per_kwh"] = tariff
    return yaml.safe_dump(raw)


def _init_db(db_path: Path) -> sqlite3.Connection:
    conn = sqlite3.connect(str(db_path))
    sql = (ROOT / "config" / "schema.sql").read_text()
    conn.executescript(sql)
    conn.close()
    return conn


def _seed_local_model(db_path: Path, model_id: str) -> sqlite3.Connection:
    conn = sqlite3.connect(str(db_path))
    conn.execute(
        """
        INSERT OR IGNORE INTO models (
            model_id, provider, base_model_id, display_name,
            context_window, effective_context_window, max_output_tokens,
            supports_tools, supports_json_mode, supports_vision,
            supports_reasoning, reasoning_default_enabled, latency_class,
            reasoning_mode, context_variant, access_level,
            pricing_tbd, deprecated, availability, last_updated, tier
        ) VALUES (?, 'ollama-local', ?, ?, 32768, 32768, 2048,
                  0, 0, 0, 0, 0, 'standard', 'default', 'full', 'public',
                  0, 0, 'active', '2026-01-01T00:00:00+00:00', 1)
        """,
        (model_id, model_id, model_id),
    )
    conn.commit()
    conn.close()
    return conn