"""
Business Rule Regression Tests
==============================
Regression tests for historical bug fixes in kit pricing, discount calculation,
duplicate CODMAT resolution, price sync, and VAT normalization.

Run:
    cd api && python -m pytest tests/test_business_rules.py -v
"""

import json
import os
import sys
import tempfile

import pytest

pytestmark = pytest.mark.unit

# --- Set env vars BEFORE any app import ---
_tmpdir = tempfile.mkdtemp()
_sqlite_path = os.path.join(_tmpdir, "test_biz.db")

os.environ["FORCE_THIN_MODE"] = "true"
os.environ["SQLITE_DB_PATH"] = _sqlite_path
os.environ["ORACLE_DSN"] = "dummy"
os.environ["ORACLE_USER"] = "dummy"
os.environ["ORACLE_PASSWORD"] = "dummy"
os.environ["JSON_OUTPUT_DIR"] = _tmpdir

_api_dir = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
if _api_dir not in sys.path:
    sys.path.insert(0, _api_dir)

from unittest.mock import MagicMock, patch

from app.services.import_service import build_articles_json, compute_discount_split
from app.services.order_reader import OrderData, OrderItem


# ---------------------------------------------------------------------------
# Helpers
# ---------------------------------------------------------------------------

def make_item(sku="SKU1", price=100.0, quantity=1, vat=19):
    return OrderItem(sku=sku, name=f"Product {sku}", price=price, quantity=quantity, vat=vat)


def make_order(items, discount_total=0.0, delivery_cost=0.0, discount_vat=None):
    order = OrderData(
        id="1", number="TEST-001", date="2026-01-01",
        items=items, discount_total=discount_total,
        delivery_cost=delivery_cost,
    )
    if discount_vat is not None:
        order.discount_vat = discount_vat
    return order


def is_kit(comps):
    """Kit detection pattern used in validation_service and price_sync_service."""
    return len(comps) > 1 or (
        len(comps) == 1 and (comps[0].get("cantitate_roa") or 1) > 1
    )


# ===========================================================================
# Group 1: compute_discount_split()
# ===========================================================================

class TestDiscountSplit:
    """Regression: discount split by VAT rate (import_service.py:63)."""

    def test_single_vat_rate(self):
        order = make_order([make_item(vat=19), make_item("SKU2", vat=19)], discount_total=10.0)
        result = compute_discount_split(order, {"split_discount_vat": "1"})
        assert result == {"19": 10.0}

    def test_multiple_vat_proportional(self):
        items = [make_item("A", price=100, quantity=1, vat=19),
                 make_item("B", price=50, quantity=1, vat=9)]
        order = make_order(items, discount_total=15.0)
        result = compute_discount_split(order, {"split_discount_vat": "1"})
        assert result == {"9": 5.0, "19": 10.0}

    def test_zero_returns_none(self):
        order = make_order([make_item()], discount_total=0)
        assert compute_discount_split(order, {"split_discount_vat": "1"}) is None

    def test_zero_price_items_excluded(self):
        items = [make_item("A", price=0, quantity=1, vat=19),
                 make_item("B", price=100, quantity=2, vat=9)]
        order = make_order(items, discount_total=5.0)
        result = compute_discount_split(order, {"split_discount_vat": "1"})
        assert result == {"9": 5.0}

    def test_disabled_multiple_rates(self):
        items = [make_item("A", vat=19), make_item("B", vat=9)]
        order = make_order(items, discount_total=10.0)
        result = compute_discount_split(order, {"split_discount_vat": "0"})
        assert result is None

    def test_rounding_remainder(self):
        items = [make_item("A", price=33.33, quantity=1, vat=19),
                 make_item("B", price=33.33, quantity=1, vat=9),
                 make_item("C", price=33.34, quantity=1, vat=5)]
        order = make_order(items, discount_total=10.0)
        result = compute_discount_split(order, {"split_discount_vat": "1"})
        assert result is not None
        assert abs(sum(result.values()) - 10.0) < 0.001


# ===========================================================================
# Group 2: build_articles_json()
# ===========================================================================

class TestBuildArticlesJson:
    """Regression: discount lines, policy bridge, transport (import_service.py:117)."""

    def test_discount_line_negative_quantity(self):
        items = [make_item()]
        order = make_order(items, discount_total=5.0)
        settings = {"discount_codmat": "DISC01", "split_discount_vat": "0"}
        result = json.loads(build_articles_json(items, order, settings))
        disc_lines = [a for a in result if a["sku"] == "DISC01"]
        assert len(disc_lines) == 1
        assert disc_lines[0]["quantity"] == "-1"
        assert disc_lines[0]["price"] == "5.0"

    def test_discount_uses_actual_vat_not_21(self):
        items = [make_item("A", vat=9), make_item("B", vat=9)]
        order = make_order(items, discount_total=3.0)
        settings = {"discount_codmat": "DISC01", "split_discount_vat": "1"}
        result = json.loads(build_articles_json(items, order, settings))
        disc_lines = [a for a in result if a["sku"] == "DISC01"]
        assert len(disc_lines) == 1
        assert disc_lines[0]["vat"] == "9"

    def test_discount_multi_vat_creates_multiple_lines(self):
        items = [make_item("A", price=100, vat=19), make_item("B", price=50, vat=9)]
        order = make_order(items, discount_total=15.0)
        settings = {"discount_codmat": "DISC01", "split_discount_vat": "1"}
        result = json.loads(build_articles_json(items, order, settings))
        disc_lines = [a for a in result if a["sku"] == "DISC01"]
        assert len(disc_lines) == 2
        vats = {d["vat"] for d in disc_lines}
        assert "9" in vats
        assert "19" in vats

    def test_discount_fallback_uses_gomag_vat(self):
        items = [make_item("A", vat=19), make_item("B", vat=9)]
        order = make_order(items, discount_total=5.0, discount_vat="9")
        settings = {"discount_codmat": "DISC01", "split_discount_vat": "0"}
        result = json.loads(build_articles_json(items, order, settings))
        disc_lines = [a for a in result if a["sku"] == "DISC01"]
        assert len(disc_lines) == 1
        assert disc_lines[0]["vat"] == "9"

    def test_per_article_policy_bridge(self):
        items = [make_item("SKU1")]
        settings = {"_codmat_policy_map": {"SKU1": 42}, "id_pol": "1"}
        result = json.loads(build_articles_json(items, settings=settings))
        assert result[0]["id_pol"] == "42"

    def test_policy_same_as_default_omitted(self):
        items = [make_item("SKU1")]
        settings = {"_codmat_policy_map": {"SKU1": 1}, "id_pol": "1"}
        result = json.loads(build_articles_json(items, settings=settings))
        assert "id_pol" not in result[0]

    def test_transport_line_added(self):
        items = [make_item()]
        order = make_order(items, delivery_cost=15.0)
        settings = {"transport_codmat": "TR", "transport_vat": "19"}
        result = json.loads(build_articles_json(items, order, settings))
        tr_lines = [a for a in result if a["sku"] == "TR"]
        assert len(tr_lines) == 1
        assert tr_lines[0]["quantity"] == "1"
        assert tr_lines[0]["price"] == "15.0"


# ===========================================================================
# Group 3: Kit Detection Pattern
# ===========================================================================

class TestKitDetection:
    """Regression: kit detection for single-component repackaging (multiple code locations)."""

    def test_multi_component(self):
        comps = [{"codmat": "A", "cantitate_roa": 1}, {"codmat": "B", "cantitate_roa": 1}]
        assert is_kit(comps) is True

    def test_single_component_repackaging(self):
        comps = [{"codmat": "CAF01", "cantitate_roa": 10}]
        assert is_kit(comps) is True

    def test_true_1to1_not_kit(self):
        comps = [{"codmat": "X", "cantitate_roa": 1}]
        assert is_kit(comps) is False

    def test_none_cantitate_treated_as_1(self):
        comps = [{"codmat": "X", "cantitate_roa": None}]
        assert is_kit(comps) is False

    def test_empty_components(self):
        assert is_kit([]) is False


# ===========================================================================
# Group 4: sync_prices_from_order() — Kit Skip Logic
# ===========================================================================

class TestSyncPricesKitSkip:
    """Regression: kit SKUs must be skipped in order-based price sync."""

    def _make_mock_order(self, sku, price=50.0):
        mock_order = MagicMock()
        mock_item = MagicMock()
        mock_item.sku = sku
        mock_item.price = price
        mock_order.items = [mock_item]
        return mock_order

    @patch("app.services.validation_service.compare_and_update_price")
    def test_skips_multi_component_kit(self, mock_compare):
        from app.services.validation_service import sync_prices_from_order
        orders = [self._make_mock_order("KIT01")]
        mapped = {"KIT01": [
            {"codmat": "A", "id_articol": 1, "cantitate_roa": 1},
            {"codmat": "B", "id_articol": 2, "cantitate_roa": 1},
        ]}
        mock_conn = MagicMock()
        sync_prices_from_order(orders, mapped, {}, {}, 1, conn=mock_conn,
                               settings={"price_sync_enabled": "1"})
        mock_compare.assert_not_called()

    @patch("app.services.validation_service.compare_and_update_price")
    def test_skips_repackaging_kit(self, mock_compare):
        from app.services.validation_service import sync_prices_from_order
        orders = [self._make_mock_order("CAFE100")]
        mapped = {"CAFE100": [
            {"codmat": "CAF01", "id_articol": 1, "cantitate_roa": 10},
        ]}
        mock_conn = MagicMock()
        sync_prices_from_order(orders, mapped, {}, {}, 1, conn=mock_conn,
                               settings={"price_sync_enabled": "1"})
        mock_compare.assert_not_called()

    @patch("app.services.validation_service.compare_and_update_price")
    def test_processes_1to1_mapping(self, mock_compare):
        from app.services.validation_service import sync_prices_from_order
        mock_compare.return_value = {"updated": False, "old_price": 50.0, "new_price": 50.0, "codmat": "X"}
        orders = [self._make_mock_order("SKU1", price=50.0)]
        mapped = {"SKU1": [
            {"codmat": "X", "id_articol": 100, "cantitate_roa": 1, "cont": "371"},
        ]}
        mock_conn = MagicMock()
        sync_prices_from_order(orders, mapped, {}, {"SKU1": 1}, 1, conn=mock_conn,
                               settings={"price_sync_enabled": "1"})
        mock_compare.assert_called_once()
        call_args = mock_compare.call_args
        assert call_args[0][0] == 100  # id_articol
        assert call_args[0][2] == 50.0  # price

    @patch("app.services.validation_service.compare_and_update_price")
    def test_skips_transport_discount_codmats(self, mock_compare):
        from app.services.validation_service import sync_prices_from_order
        orders = [self._make_mock_order("TRANSP", price=15.0)]
        mock_conn = MagicMock()
        sync_prices_from_order(orders, {}, {"TRANSP": {"id_articol": 99}}, {}, 1,
                               conn=mock_conn,
                               settings={"price_sync_enabled": "1",
                                         "transport_codmat": "TRANSP",
                                         "discount_codmat": "DISC"})
        mock_compare.assert_not_called()


# ===========================================================================
# Group 5: Kit Component with Own Mapping
# ===========================================================================

class TestKitComponentOwnMapping:
    """Regression: price_sync_service skips kit components that have their own ARTICOLE_TERTI mapping."""

    def test_component_with_own_mapping_skipped(self):
        """If comp_codmat is itself a key in mapped_data, it's skipped."""
        mapped_data = {
            "PACK-A": [{"codmat": "COMP-X", "id_articol": 1, "cantitate_roa": 1, "cont": "371"}],
            "COMP-X": [{"codmat": "COMP-X", "id_articol": 1, "cantitate_roa": 1, "cont": "371"}],
        }
        # The check is: if comp_codmat in mapped_data: continue
        comp_codmat = "COMP-X"
        assert comp_codmat in mapped_data  # Should be skipped

    def test_component_without_own_mapping_processed(self):
        """If comp_codmat is NOT in mapped_data, it should be processed."""
        mapped_data = {
            "PACK-A": [{"codmat": "COMP-Y", "id_articol": 2, "cantitate_roa": 1, "cont": "371"}],
        }
        comp_codmat = "COMP-Y"
        assert comp_codmat not in mapped_data  # Should be processed


# ===========================================================================
# Group 6: VAT Included Type Normalization
# ===========================================================================

class TestVatIncludedNormalization:
    """Regression: GoMag returns vat_included as int 1 or string '1' (price_sync_service.py:144)."""

    def _compute_price_cu_tva(self, product):
        price = float(product.get("price", "0"))
        vat = float(product.get("vat", "19"))
        if str(product.get("vat_included", "1")) == "1":
            return price
        else:
            return price * (1 + vat / 100)

    def test_vat_included_int_1(self):
        result = self._compute_price_cu_tva({"price": "100", "vat": "19", "vat_included": 1})
        assert result == 100.0

    def test_vat_included_str_1(self):
        result = self._compute_price_cu_tva({"price": "100", "vat": "19", "vat_included": "1"})
        assert result == 100.0

    def test_vat_included_int_0(self):
        result = self._compute_price_cu_tva({"price": "100", "vat": "19", "vat_included": 0})
        assert result == 119.0

    def test_vat_included_str_0(self):
        result = self._compute_price_cu_tva({"price": "100", "vat": "19", "vat_included": "0"})
        assert result == 119.0


# ===========================================================================
# Group 7: validate_kit_component_prices — pret=0 allowed
# ===========================================================================

class TestKitComponentPriceValidation:
    """Regression: pret=0 in CRM is valid for kit components (validation_service.py:469)."""

    def _call_validate(self, fetchone_returns):
        from app.services.validation_service import validate_kit_component_prices

        mock_conn = MagicMock()
        mock_cursor = MagicMock()
        mock_conn.cursor.return_value.__enter__ = MagicMock(return_value=mock_cursor)
        mock_conn.cursor.return_value.__exit__ = MagicMock(return_value=False)
        mock_cursor.fetchone.return_value = fetchone_returns

        mapped = {"KIT-SKU": [
            {"codmat": "COMP1", "id_articol": 100, "cont": "371", "cantitate_roa": 5},
        ]}
        return validate_kit_component_prices(mapped, id_pol=1, conn=mock_conn)

    def test_price_zero_not_rejected(self):
        result = self._call_validate((0,))
        assert result == {}

    def test_missing_entry_rejected(self):
        result = self._call_validate(None)
        assert "KIT-SKU" in result
        assert "COMP1" in result["KIT-SKU"]

    def test_skips_true_1to1(self):
        from app.services.validation_service import validate_kit_component_prices
        mock_conn = MagicMock()
        mapped = {"SKU1": [
            {"codmat": "X", "id_articol": 1, "cont": "371", "cantitate_roa": 1},
        ]}
        result = validate_kit_component_prices(mapped, id_pol=1, conn=mock_conn)
        assert result == {}

    def test_checks_repackaging(self):
        """Single component with cantitate_roa > 1 should be checked."""
        from app.services.validation_service import validate_kit_component_prices

        mock_conn = MagicMock()
        mock_cursor = MagicMock()
        mock_conn.cursor.return_value.__enter__ = MagicMock(return_value=mock_cursor)
        mock_conn.cursor.return_value.__exit__ = MagicMock(return_value=False)
        mock_cursor.fetchone.return_value = (51.50,)

        mapped = {"CAFE100": [
            {"codmat": "CAF01", "id_articol": 100, "cont": "371", "cantitate_roa": 10},
        ]}
        result = validate_kit_component_prices(mapped, id_pol=1, conn=mock_conn)
        assert result == {}
        mock_cursor.execute.assert_called_once()


# ===========================================================================
# Group 8: Dual Policy Assignment
# ===========================================================================

class TestDualPolicyAssignment:
    """Regression: cont 341/345 → production policy, others → sales (validation_service.py:282)."""

    def _call_dual(self, codmats, direct_id_map, cursor_rows):
        from app.services.validation_service import validate_and_ensure_prices_dual

        mock_conn = MagicMock()
        mock_cursor = MagicMock()
        mock_conn.cursor.return_value.__enter__ = MagicMock(return_value=mock_cursor)
        mock_conn.cursor.return_value.__exit__ = MagicMock(return_value=False)
        # The code uses `for row in cur:` to iterate, not fetchall
        mock_cursor.__iter__ = MagicMock(return_value=iter(cursor_rows))
        # Mock ensure_prices to do nothing
        with patch("app.services.validation_service.ensure_prices"):
            return validate_and_ensure_prices_dual(
                codmats, id_pol_vanzare=1, id_pol_productie=2,
                conn=mock_conn, direct_id_map=direct_id_map
            )

    def test_cont_341_production(self):
        result = self._call_dual(
            {"COD1"},
            {"COD1": {"id_articol": 100, "cont": "341"}},
            []  # no existing prices
        )
        assert result["COD1"] == 2  # id_pol_productie

    def test_cont_345_production(self):
        result = self._call_dual(
            {"COD1"},
            {"COD1": {"id_articol": 100, "cont": "345"}},
            []
        )
        assert result["COD1"] == 2

    def test_other_cont_sales(self):
        result = self._call_dual(
            {"COD1"},
            {"COD1": {"id_articol": 100, "cont": "371"}},
            []
        )
        assert result["COD1"] == 1  # id_pol_vanzare

    def test_existing_sales_preferred(self):
        result = self._call_dual(
            {"COD1"},
            {"COD1": {"id_articol": 100, "cont": "345"}},
            [(100, 1), (100, 2)]  # price exists in BOTH policies
        )
        assert result["COD1"] == 1  # sales preferred when both exist


# ===========================================================================
# Group 9: Duplicate CODMAT — resolve_codmat_ids
# ===========================================================================

class TestResolveCodmatIds:
    """Regression: ROW_NUMBER dedup returns exactly 1 id_articol per CODMAT."""

    @patch("app.services.validation_service.database")
    def test_returns_one_per_codmat(self, mock_db):
        from app.services.validation_service import resolve_codmat_ids

        mock_conn = MagicMock()
        mock_cursor = MagicMock()
        mock_conn.cursor.return_value.__enter__ = MagicMock(return_value=mock_cursor)
        mock_conn.cursor.return_value.__exit__ = MagicMock(return_value=False)
        # Simulate ROW_NUMBER already deduped: 1 row per codmat
        mock_cursor.__iter__ = MagicMock(return_value=iter([
            ("COD1", 100, "345"),
            ("COD2", 200, "341"),
        ]))

        result = resolve_codmat_ids({"COD1", "COD2"}, conn=mock_conn)
        assert len(result) == 2
        assert result["COD1"]["id_articol"] == 100
        assert result["COD2"]["id_articol"] == 200

    @patch("app.services.validation_service.database")
    def test_resolve_mapped_one_per_sku_codmat(self, mock_db):
        from app.services.validation_service import resolve_mapped_codmats

        mock_conn = MagicMock()
        mock_cursor = MagicMock()
        mock_conn.cursor.return_value.__enter__ = MagicMock(return_value=mock_cursor)
        mock_conn.cursor.return_value.__exit__ = MagicMock(return_value=False)
        # 1 row per (sku, codmat) pair
        mock_cursor.__iter__ = MagicMock(return_value=iter([
            ("SKU1", "COD1", 100, "345", 10),
            ("SKU1", "COD2", 200, "341", 1),
        ]))

        result = resolve_mapped_codmats({"SKU1"}, mock_conn)
        assert "SKU1" in result
        assert len(result["SKU1"]) == 2
        codmats = [c["codmat"] for c in result["SKU1"]]
        assert "COD1" in codmats
        assert "COD2" in codmats