"""Tests for the rationale backfill endpoint logic."""
import sys
sys.path.insert(0, ".")

import pytest
from unittest.mock import AsyncMock, MagicMock, patch

from compliance.api.canonical_control_routes import backfill_rationale


class TestRationaleBackfillDryRun:
    """Dry-run mode should return statistics without touching DB."""

    @pytest.mark.asyncio
    async def test_dry_run_returns_stats(self):
        mock_parents = [
            MagicMock(
                parent_uuid="uuid-1",
                control_id="ACC-001",
                title="Access Control",
                category="access",
                source_name="OWASP ASVS",
                child_count=12,
            ),
            MagicMock(
                parent_uuid="uuid-2",
                control_id="SEC-042",
                title="Encryption",
                category="encryption",
                source_name="NIST SP 800-53",
                child_count=5,
            ),
        ]

        with patch("compliance.api.canonical_control_routes.SessionLocal") as mock_session:
            db = MagicMock()
            mock_session.return_value.__enter__ = MagicMock(return_value=db)
            mock_session.return_value.__exit__ = MagicMock(return_value=False)
            db.execute.return_value.fetchall.return_value = mock_parents

            result = await backfill_rationale(dry_run=True, batch_size=50, offset=0)

        assert result["dry_run"] is True
        assert result["total_parents"] == 2
        assert result["total_children"] == 17
        assert result["estimated_llm_calls"] == 2
        assert len(result["sample_parents"]) == 2
        assert result["sample_parents"][0]["control_id"] == "ACC-001"


class TestRationaleBackfillExecution:
    """Execution mode should call LLM and update DB."""

    @pytest.mark.asyncio
    async def test_processes_batch_and_updates(self):
        mock_parents = [
            MagicMock(
                parent_uuid="uuid-1",
                control_id="ACC-001",
                title="Access Control",
                category="access",
                source_name="OWASP ASVS",
                child_count=5,
            ),
        ]

        mock_llm_response = MagicMock()
        mock_llm_response.content = (
            "Die uebergeordneten Anforderungen an Zugriffskontrolle aus "
            "OWASP ASVS erfordern eine Zerlegung in atomare Massnahmen, "
            "um jede Einzelmassnahme unabhaengig testbar zu machen."
        )

        mock_update_result = MagicMock()
        mock_update_result.rowcount = 5

        with patch("compliance.api.canonical_control_routes.SessionLocal") as mock_session:
            db = MagicMock()
            mock_session.return_value.__enter__ = MagicMock(return_value=db)
            mock_session.return_value.__exit__ = MagicMock(return_value=False)
            db.execute.return_value.fetchall.return_value = mock_parents
            # Second call is the UPDATE
            db.execute.return_value.rowcount = 5

            with patch("compliance.services.llm_provider.get_llm_provider") as mock_get:
                mock_provider = AsyncMock()
                mock_provider.complete.return_value = mock_llm_response
                mock_get.return_value = mock_provider

                result = await backfill_rationale(
                    dry_run=False, batch_size=50, offset=0,
                )

        assert result["dry_run"] is False
        assert result["processed_parents"] == 1
        assert len(result["errors"]) == 0
        assert len(result["sample_rationales"]) == 1

    @pytest.mark.asyncio
    async def test_empty_batch_returns_done(self):
        with patch("compliance.api.canonical_control_routes.SessionLocal") as mock_session:
            db = MagicMock()
            mock_session.return_value.__enter__ = MagicMock(return_value=db)
            mock_session.return_value.__exit__ = MagicMock(return_value=False)
            db.execute.return_value.fetchall.return_value = []

            result = await backfill_rationale(
                dry_run=False, batch_size=50, offset=9999,
            )

        assert result["processed"] == 0
        assert "Kein weiterer Batch" in result["message"]

    @pytest.mark.asyncio
    async def test_llm_error_captured(self):
        mock_parents = [
            MagicMock(
                parent_uuid="uuid-1",
                control_id="SEC-100",
                title="Network Security",
                category="network",
                source_name="ISO 27001",
                child_count=3,
            ),
        ]

        with patch("compliance.api.canonical_control_routes.SessionLocal") as mock_session:
            db = MagicMock()
            mock_session.return_value.__enter__ = MagicMock(return_value=db)
            mock_session.return_value.__exit__ = MagicMock(return_value=False)
            db.execute.return_value.fetchall.return_value = mock_parents

            with patch("compliance.services.llm_provider.get_llm_provider") as mock_get:
                mock_provider = AsyncMock()
                mock_provider.complete.side_effect = Exception("Ollama timeout")
                mock_get.return_value = mock_provider

                result = await backfill_rationale(
                    dry_run=False, batch_size=50, offset=0,
                )

        assert result["processed_parents"] == 0
        assert len(result["errors"]) == 1
        assert "Ollama timeout" in result["errors"][0]["error"]

    @pytest.mark.asyncio
    async def test_short_response_skipped(self):
        mock_parents = [
            MagicMock(
                parent_uuid="uuid-1",
                control_id="GOV-001",
                title="Governance",
                category="governance",
                source_name="ISO 27001",
                child_count=2,
            ),
        ]

        mock_llm_response = MagicMock()
        mock_llm_response.content = "OK"  # Too short

        with patch("compliance.api.canonical_control_routes.SessionLocal") as mock_session:
            db = MagicMock()
            mock_session.return_value.__enter__ = MagicMock(return_value=db)
            mock_session.return_value.__exit__ = MagicMock(return_value=False)
            db.execute.return_value.fetchall.return_value = mock_parents

            with patch("compliance.services.llm_provider.get_llm_provider") as mock_get:
                mock_provider = AsyncMock()
                mock_provider.complete.return_value = mock_llm_response
                mock_get.return_value = mock_provider

                result = await backfill_rationale(
                    dry_run=False, batch_size=50, offset=0,
                )

        assert result["processed_parents"] == 0
        assert len(result["errors"]) == 1
        assert "zu kurz" in result["errors"][0]["error"]


class TestRationalePagination:
    """Pagination logic should work correctly."""

    @pytest.mark.asyncio
    async def test_next_offset_set_when_more_remain(self):
        # 3 parents, batch_size=2 → next_offset=2
        mock_parents = [
            MagicMock(
                parent_uuid=f"uuid-{i}",
                control_id=f"SEC-{i:03d}",
                title=f"Control {i}",
                category="security",
                source_name="NIST",
                child_count=2,
            )
            for i in range(3)
        ]

        mock_llm_response = MagicMock()
        mock_llm_response.content = (
            "Sicherheitsanforderungen aus NIST erfordern atomare "
            "Massnahmen fuer unabhaengige Testbarkeit."
        )

        with patch("compliance.api.canonical_control_routes.SessionLocal") as mock_session:
            db = MagicMock()
            mock_session.return_value.__enter__ = MagicMock(return_value=db)
            mock_session.return_value.__exit__ = MagicMock(return_value=False)
            db.execute.return_value.fetchall.return_value = mock_parents
            db.execute.return_value.rowcount = 2

            with patch("compliance.services.llm_provider.get_llm_provider") as mock_get:
                mock_provider = AsyncMock()
                mock_provider.complete.return_value = mock_llm_response
                mock_get.return_value = mock_provider

                result = await backfill_rationale(
                    dry_run=False, batch_size=2, offset=0,
                )

        assert result["next_offset"] == 2
        assert result["processed_parents"] == 2

    @pytest.mark.asyncio
    async def test_next_offset_none_when_done(self):
        mock_parents = [
            MagicMock(
                parent_uuid="uuid-1",
                control_id="SEC-001",
                title="Control 1",
                category="security",
                source_name="NIST",
                child_count=2,
            ),
        ]

        mock_llm_response = MagicMock()
        mock_llm_response.content = (
            "Sicherheitsanforderungen erfordern atomare Massnahmen."
        )

        with patch("compliance.api.canonical_control_routes.SessionLocal") as mock_session:
            db = MagicMock()
            mock_session.return_value.__enter__ = MagicMock(return_value=db)
            mock_session.return_value.__exit__ = MagicMock(return_value=False)
            db.execute.return_value.fetchall.return_value = mock_parents
            db.execute.return_value.rowcount = 2

            with patch("compliance.services.llm_provider.get_llm_provider") as mock_get:
                mock_provider = AsyncMock()
                mock_provider.complete.return_value = mock_llm_response
                mock_get.return_value = mock_provider

                result = await backfill_rationale(
                    dry_run=False, batch_size=50, offset=0,
                )

        assert result["next_offset"] is None