"""
Deep behavioral tests for news filtering patterns.
Tests category filtering, topic filtering, time filtering,
impact filtering, and combined filter logic.
"""

from datetime import datetime, timezone, timedelta


# --- Category filtering patterns ---


class TestCategoryFiltering:
    """Tests for category-based filtering."""

    def _filter_by_category(self, items, category):
        """Filter items by category."""
        if not category or category == "all":
            return items
        return [i for i in items if i.get("category") == category]

    def test_filters_matching(self):
        items = [
            {"id": "1", "category": "Tech"},
            {"id": "2", "category": "Science"},
            {"id": "3", "category": "Tech"},
        ]
        result = self._filter_by_category(items, "Tech")
        assert len(result) == 2
        assert all(i["category"] == "Tech" for i in result)

    def test_no_match_returns_empty(self):
        items = [{"id": "1", "category": "Tech"}]
        result = self._filter_by_category(items, "Sports")
        assert result == []

    def test_all_category_returns_all(self):
        items = [{"id": "1"}, {"id": "2"}]
        result = self._filter_by_category(items, "all")
        assert len(result) == 2

    def test_none_category_returns_all(self):
        items = [{"id": "1"}, {"id": "2"}]
        result = self._filter_by_category(items, None)
        assert len(result) == 2


class TestMultipleCategoryFiltering:
    """Tests for filtering by multiple categories."""

    def _filter_by_categories(self, items, categories):
        """Filter items by multiple categories."""
        if not categories:
            return items
        return [i for i in items if i.get("category") in categories]

    def test_multiple_categories(self):
        items = [
            {"id": "1", "category": "Tech"},
            {"id": "2", "category": "Science"},
            {"id": "3", "category": "Sports"},
        ]
        result = self._filter_by_categories(items, ["Tech", "Science"])
        assert len(result) == 2

    def test_single_category_in_list(self):
        items = [
            {"id": "1", "category": "Tech"},
            {"id": "2", "category": "Science"},
        ]
        result = self._filter_by_categories(items, ["Tech"])
        assert len(result) == 1


# --- Topic filtering patterns ---


class TestTopicFiltering:
    """Tests for topic-based filtering."""

    def _filter_by_topic(self, items, topic):
        """Filter items containing a topic."""
        if not topic:
            return items
        topic_lower = topic.lower()
        return [
            i
            for i in items
            if any(topic_lower in t.lower() for t in i.get("topics", []))
        ]

    def test_filters_matching_topic(self):
        items = [
            {"id": "1", "topics": ["AI", "ML"]},
            {"id": "2", "topics": ["Climate"]},
        ]
        result = self._filter_by_topic(items, "AI")
        assert len(result) == 1
        assert result[0]["id"] == "1"

    def test_case_insensitive(self):
        items = [{"id": "1", "topics": ["Artificial Intelligence"]}]
        result = self._filter_by_topic(items, "artificial")
        assert len(result) == 1

    def test_partial_match(self):
        items = [{"id": "1", "topics": ["Climate Change"]}]
        result = self._filter_by_topic(items, "climate")
        assert len(result) == 1

    def test_no_topic_returns_all(self):
        items = [{"id": "1"}, {"id": "2"}]
        result = self._filter_by_topic(items, None)
        assert len(result) == 2


class TestMultipleTopicFiltering:
    """Tests for filtering by multiple topics."""

    def _filter_by_topics(self, items, topics, match_all=False):
        """Filter items by multiple topics."""
        if not topics:
            return items
        topics_lower = [t.lower() for t in topics]
        result = []
        for item in items:
            item_topics = [t.lower() for t in item.get("topics", [])]
            if match_all:
                matches = all(
                    any(t in it for it in item_topics) for t in topics_lower
                )
            else:
                matches = any(
                    any(t in it for it in item_topics) for t in topics_lower
                )
            if matches:
                result.append(item)
        return result

    def test_match_any(self):
        items = [
            {"id": "1", "topics": ["AI"]},
            {"id": "2", "topics": ["Climate"]},
        ]
        result = self._filter_by_topics(items, ["AI", "Climate"])
        assert len(result) == 2

    def test_match_all(self):
        items = [
            {"id": "1", "topics": ["AI", "ML"]},
            {"id": "2", "topics": ["AI"]},
        ]
        result = self._filter_by_topics(items, ["AI", "ML"], match_all=True)
        assert len(result) == 1


# --- Time filtering patterns ---


class TestTimeFiltering:
    """Tests for time-based filtering."""

    def _filter_by_time(self, items, hours):
        """Filter items from the last N hours."""
        if not hours:
            return items
        cutoff = datetime.now(timezone.utc) - timedelta(hours=hours)
        return [i for i in items if i.get("created_at", cutoff) >= cutoff]

    def test_filters_recent(self):
        now = datetime.now(timezone.utc)
        old = now - timedelta(hours=48)
        items = [
            {"id": "1", "created_at": now},
            {"id": "2", "created_at": old},
        ]
        result = self._filter_by_time(items, 24)
        assert len(result) == 1
        assert result[0]["id"] == "1"

    def test_all_within_range(self):
        now = datetime.now(timezone.utc)
        items = [{"id": str(i), "created_at": now} for i in range(5)]
        result = self._filter_by_time(items, 24)
        assert len(result) == 5

    def test_none_hours_returns_all(self):
        items = [{"id": "1"}, {"id": "2"}]
        result = self._filter_by_time(items, None)
        assert len(result) == 2


class TestDateRangeFiltering:
    """Tests for date range filtering."""

    def _filter_by_date_range(self, items, start_date, end_date):
        """Filter items within a date range."""
        result = []
        for item in items:
            created = item.get("created_at")
            if not created:
                continue
            if start_date and created < start_date:
                continue
            if end_date and created > end_date:
                continue
            result.append(item)
        return result

    def test_within_range(self):
        start = datetime(2025, 6, 1, tzinfo=timezone.utc)
        end = datetime(2025, 6, 30, tzinfo=timezone.utc)
        items = [
            {
                "id": "1",
                "created_at": datetime(2025, 6, 15, tzinfo=timezone.utc),
            },
            {
                "id": "2",
                "created_at": datetime(2025, 5, 15, tzinfo=timezone.utc),
            },
        ]
        result = self._filter_by_date_range(items, start, end)
        assert len(result) == 1

    def test_no_start(self):
        end = datetime(2025, 6, 30, tzinfo=timezone.utc)
        items = [
            {
                "id": "1",
                "created_at": datetime(2025, 6, 15, tzinfo=timezone.utc),
            }
        ]
        result = self._filter_by_date_range(items, None, end)
        assert len(result) == 1

    def test_no_end(self):
        start = datetime(2025, 6, 1, tzinfo=timezone.utc)
        items = [
            {
                "id": "1",
                "created_at": datetime(2025, 6, 15, tzinfo=timezone.utc),
            }
        ]
        result = self._filter_by_date_range(items, start, None)
        assert len(result) == 1


# --- Impact filtering patterns ---


class TestImpactFiltering:
    """Tests for impact score filtering."""

    def _filter_by_impact(self, items, min_impact=0, max_impact=10):
        """Filter items by impact score range."""
        return [
            i
            for i in items
            if min_impact <= i.get("impact_score", 5) <= max_impact
        ]

    def test_min_impact(self):
        items = [
            {"id": "1", "impact_score": 3},
            {"id": "2", "impact_score": 7},
            {"id": "3", "impact_score": 9},
        ]
        result = self._filter_by_impact(items, min_impact=5)
        assert len(result) == 2

    def test_max_impact(self):
        items = [
            {"id": "1", "impact_score": 3},
            {"id": "2", "impact_score": 7},
        ]
        result = self._filter_by_impact(items, max_impact=5)
        assert len(result) == 1

    def test_range(self):
        items = [
            {"id": "1", "impact_score": 3},
            {"id": "2", "impact_score": 5},
            {"id": "3", "impact_score": 9},
        ]
        result = self._filter_by_impact(items, min_impact=4, max_impact=6)
        assert len(result) == 1

    def test_default_impact_5(self):
        items = [{"id": "1"}]  # No impact_score
        result = self._filter_by_impact(items, min_impact=5, max_impact=5)
        assert len(result) == 1  # Default is 5


class TestHighImpactFiltering:
    """Tests for high impact filtering."""

    def _filter_high_impact(self, items, threshold=7):
        """Filter high impact items."""
        return [i for i in items if i.get("impact_score", 0) >= threshold]

    def test_filters_high_impact(self):
        items = [
            {"id": "1", "impact_score": 5},
            {"id": "2", "impact_score": 8},
            {"id": "3", "impact_score": 9},
        ]
        result = self._filter_high_impact(items)
        assert len(result) == 2

    def test_custom_threshold(self):
        items = [{"id": "1", "impact_score": 5}]
        result = self._filter_high_impact(items, threshold=4)
        assert len(result) == 1


# --- Status filtering patterns ---


class TestStatusFiltering:
    """Tests for status-based filtering."""

    def _filter_by_status(self, items, status):
        """Filter items by status."""
        if not status:
            return items
        return [i for i in items if i.get("status") == status]

    def test_active_only(self):
        items = [
            {"id": "1", "status": "active"},
            {"id": "2", "status": "archived"},
        ]
        result = self._filter_by_status(items, "active")
        assert len(result) == 1

    def test_archived_only(self):
        items = [
            {"id": "1", "status": "active"},
            {"id": "2", "status": "archived"},
        ]
        result = self._filter_by_status(items, "archived")
        assert len(result) == 1


class TestExcludeStatuses:
    """Tests for excluding certain statuses."""

    def _exclude_statuses(self, items, exclude_list):
        """Exclude items with certain statuses."""
        if not exclude_list:
            return items
        return [i for i in items if i.get("status") not in exclude_list]

    def test_excludes_archived(self):
        items = [
            {"id": "1", "status": "active"},
            {"id": "2", "status": "archived"},
        ]
        result = self._exclude_statuses(items, ["archived"])
        assert len(result) == 1
        assert result[0]["status"] == "active"

    def test_excludes_multiple(self):
        items = [
            {"id": "1", "status": "active"},
            {"id": "2", "status": "archived"},
            {"id": "3", "status": "deleted"},
        ]
        result = self._exclude_statuses(items, ["archived", "deleted"])
        assert len(result) == 1


# --- Source filtering patterns ---


class TestSourceFiltering:
    """Tests for source-based filtering."""

    def _filter_by_source(self, items, source_type):
        """Filter items by source type."""
        if not source_type:
            return items
        return [
            i for i in items if i.get("source", {}).get("type") == source_type
        ]

    def test_filters_by_source(self):
        items = [
            {"id": "1", "source": {"type": "subscription"}},
            {"id": "2", "source": {"type": "trending"}},
        ]
        result = self._filter_by_source(items, "subscription")
        assert len(result) == 1

    def test_no_source_type_returns_all(self):
        items = [{"id": "1"}, {"id": "2"}]
        result = self._filter_by_source(items, None)
        assert len(result) == 2


# --- Combined filter patterns ---


class TestCombinedFilters:
    """Tests for combining multiple filters."""

    def _apply_filters(self, items, filters):
        """Apply multiple filters."""
        result = items
        if filters.get("category"):
            result = [
                i for i in result if i.get("category") == filters["category"]
            ]
        if filters.get("min_impact"):
            result = [
                i
                for i in result
                if i.get("impact_score", 0) >= filters["min_impact"]
            ]
        if filters.get("status"):
            result = [i for i in result if i.get("status") == filters["status"]]
        return result

    def test_category_and_impact(self):
        items = [
            {"id": "1", "category": "Tech", "impact_score": 8},
            {"id": "2", "category": "Tech", "impact_score": 3},
            {"id": "3", "category": "Science", "impact_score": 9},
        ]
        result = self._apply_filters(
            items, {"category": "Tech", "min_impact": 5}
        )
        assert len(result) == 1
        assert result[0]["id"] == "1"

    def test_no_filters(self):
        items = [{"id": "1"}, {"id": "2"}]
        result = self._apply_filters(items, {})
        assert len(result) == 2


# --- Viewed filter patterns ---


class TestViewedFiltering:
    """Tests for filtering by viewed status."""

    def _filter_viewed(self, items, include_viewed=True):
        """Filter items by viewed status."""
        if include_viewed:
            return items
        return [i for i in items if not i.get("interaction", {}).get("viewed")]

    def test_include_viewed(self):
        items = [
            {"id": "1", "interaction": {"viewed": True}},
            {"id": "2", "interaction": {"viewed": False}},
        ]
        result = self._filter_viewed(items, include_viewed=True)
        assert len(result) == 2

    def test_exclude_viewed(self):
        items = [
            {"id": "1", "interaction": {"viewed": True}},
            {"id": "2", "interaction": {"viewed": False}},
        ]
        result = self._filter_viewed(items, include_viewed=False)
        assert len(result) == 1
        assert result[0]["id"] == "2"


# --- Subscription filter patterns ---


class TestSubscriptionFiltering:
    """Tests for subscription-based filtering."""

    def _filter_by_subscription(self, items, subscription_id):
        """Filter items by subscription."""
        if not subscription_id or subscription_id == "all":
            return items
        return [i for i in items if i.get("subscription_id") == subscription_id]

    def test_filters_by_subscription(self):
        items = [
            {"id": "1", "subscription_id": "sub-1"},
            {"id": "2", "subscription_id": "sub-2"},
        ]
        result = self._filter_by_subscription(items, "sub-1")
        assert len(result) == 1

    def test_all_subscription(self):
        items = [{"id": "1"}, {"id": "2"}]
        result = self._filter_by_subscription(items, "all")
        assert len(result) == 2


# --- User filter patterns ---


class TestUserFiltering:
    """Tests for user-based filtering."""

    def _filter_by_user(self, items, user_id):
        """Filter items by user."""
        if not user_id:
            return items
        return [i for i in items if i.get("user_id") == user_id]

    def test_filters_by_user(self):
        items = [
            {"id": "1", "user_id": "u1"},
            {"id": "2", "user_id": "u2"},
            {"id": "3", "user_id": "u1"},
        ]
        result = self._filter_by_user(items, "u1")
        assert len(result) == 2

    def test_no_user_returns_all(self):
        items = [{"id": "1"}, {"id": "2"}]
        result = self._filter_by_user(items, None)
        assert len(result) == 2


# --- Search query filter patterns ---


class TestSearchQueryFiltering:
    """Tests for search query filtering."""

    def _filter_by_query(self, items, query):
        """Filter items by search query."""
        if not query:
            return items
        query_lower = query.lower()
        return [
            i
            for i in items
            if query_lower in i.get("headline", "").lower()
            or query_lower in i.get("summary", "").lower()
        ]

    def test_matches_headline(self):
        items = [
            {"id": "1", "headline": "AI News Today"},
            {"id": "2", "headline": "Weather Report"},
        ]
        result = self._filter_by_query(items, "AI")
        assert len(result) == 1

    def test_matches_summary(self):
        items = [
            {"id": "1", "summary": "Discussion about artificial intelligence"},
        ]
        result = self._filter_by_query(items, "artificial")
        assert len(result) == 1

    def test_case_insensitive(self):
        items = [{"id": "1", "headline": "AI NEWS"}]
        result = self._filter_by_query(items, "ai")
        assert len(result) == 1
