from __future__ import annotations

import pytest

from daglib.set import DAGSetView


class TestDAGSetInit:
    """Test DAGSet initialization."""

    def test_empty(self) -> None:
        s = DAGSetView()
        assert len(s) == 0
        assert set(s) == set()
        assert list(s) == []
        assert tuple(s) == ()

    def test_from_set(self) -> None:
        s = DAGSetView({1, 2, 3})
        assert len(s) == 3
        assert set(s) == {1, 2, 3}

    def test_from_list(self) -> None:
        s = DAGSetView([1, 2, 3, 2])
        assert len(s) == 3
        assert set(s) == {1, 2, 3}

    def test_from_tuple(self) -> None:
        s = DAGSetView((4, 5, 6))
        assert len(s) == 3
        assert set(s) == {4, 5, 6}

    def test_from_none(self) -> None:
        s = DAGSetView(None)
        assert len(s) == 0

    def test_from_invalid_type(self) -> None:
        with pytest.raises(TypeError):
            DAGSetView(42)  # type: ignore


class TestDAGSetBasicOps:
    """Test basic set operations."""

    def test_len(self) -> None:
        s = DAGSetView({1, 2, 3})
        assert len(s) == 3

    def test_iter(self) -> None:
        s = DAGSetView({1, 2, 3})
        for i, v in enumerate(s):
            assert v == i + 1

    def test_contains(self) -> None:
        s = DAGSetView({1, 2, 3})
        assert 1 in s
        assert 2 in s
        assert 3 in s
        assert 4 not in s

    def test_add(self) -> None:
        s = DAGSetView()
        s.add(1)
        assert 1 in s
        assert len(s) == 1

    def test_discard(self) -> None:
        s = DAGSetView({1, 2, 3})
        s.discard(2)
        assert 2 not in s
        assert len(s) == 2

    def test_discard_missing(self) -> None:
        s = DAGSetView({1, 2, 3})
        s.discard(99)
        assert len(s) == 3

    def test_remove(self) -> None:
        s = DAGSetView({1, 2, 3})
        s.remove(2)
        assert 2 not in s

    def test_remove_missing(self) -> None:
        s = DAGSetView({1, 2, 3})
        with pytest.raises(KeyError):
            s.remove(99)


class TestDAGSetCallbacks:
    """Test callback mechanisms."""

    class TestBasicOps:
        def test_on_add_callback(self) -> None:
            added: list[int] = []
            s = DAGSetView({1, 2})
            s.on_add = lambda v: added.append(v)
            s.add(3)
            assert 3 in added
            assert len(added) == 1

        def test_on_remove_callback(self) -> None:
            removed: list[int] = []
            s = DAGSetView({1, 2, 3})
            s.on_remove = lambda v: removed.append(v)
            s.discard(2)
            assert 2 in removed
            assert len(removed) == 1

        def test_callbacks_none_by_default(self) -> None:
            s = DAGSetView()
            assert s.on_add is None
            assert s.on_remove is None

    class TestInPlaceOperators:
        def test_ior_triggers_callbacks(self) -> None:
            added: list[int] = []
            s = DAGSetView({1})
            s.on_add = lambda v: added.append(v)
            s |= {2, 3}
            assert 2 in added
            assert 3 in added

        def test_iadd_triggers_callbacks(self) -> None:
            added: list[int] = []
            s = DAGSetView({1})
            s.on_add = lambda v: added.append(v)
            s += [2, 3]
            assert 2 in added
            assert 3 in added

        def test_isub_triggers_callbacks(self) -> None:
            removed: list[int] = []
            s = DAGSetView({1, 2, 3})
            s.on_remove = lambda v: removed.append(v)
            s -= {2, 3}
            assert 2 in removed
            assert 3 in removed


class TestDAGSetInPlaceOperators:
    """Test in-place set operators."""

    class TestIOR:
        def test_set(self) -> None:
            s = DAGSetView({1, 2})
            s |= {3, 4}
            assert set(s) == {1, 2, 3, 4}

        def test_list(self) -> None:
            s = DAGSetView({1})
            s |= [2, 3]
            assert set(s) == {1, 2, 3}

        def test_string(self) -> None:
            s = DAGSetView({"abc", "def"})
            s |= "xyz"
            assert "xyz" in s

        def test_dagset(self) -> None:
            s = DAGSetView({1, 2})
            other = DAGSetView({3, 4})
            s |= other
            assert set(s) == {1, 2, 3, 4}

    class TestIAdd:
        def test_set(self) -> None:
            s = DAGSetView({1, 2})
            s += {3, 4}
            assert set(s) == {1, 2, 3, 4}

        def test_list(self) -> None:
            s = DAGSetView({1})
            s += [2, 3]
            assert set(s) == {1, 2, 3}

        def test_string(self) -> None:
            s = DAGSetView({"a"})
            s += "b"
            assert "b" in s

        def test_dagset(self) -> None:
            s = DAGSetView({1, 2})
            other = DAGSetView({3, 4})
            s += other
            assert set(s) == {1, 2, 3, 4}

    class TestISub:
        def test_set(self) -> None:
            s = DAGSetView({1, 2, 3, 4})
            s -= {2, 3}
            assert set(s) == {1, 4}

        def test_list(self) -> None:
            s = DAGSetView({1, 2, 3})
            s -= [2]
            assert set(s) == {1, 3}

        def test_string(self) -> None:
            s = DAGSetView({"a", "b", "c"})
            s -= "b"
            assert set(s) == {"a", "c"}

        def test_dagset(self) -> None:
            s = DAGSetView({1, 2, 3, 4})
            other = DAGSetView({2, 3})
            s -= other
            assert set(s) == {1, 4}

    class TestIAnd:
        def test_set(self) -> None:
            s = DAGSetView({1, 2, 3})
            s &= {2, 3, 4}
            assert set(s) == {2, 3}

        def test_list(self) -> None:
            s = DAGSetView({1, 2, 3})
            s &= [2, 3]
            assert set(s) == {2, 3}

        def test_dagset(self) -> None:
            s = DAGSetView({1, 2, 3})
            other = DAGSetView({2, 3, 4})
            s &= other
            assert set(s) == {2, 3}

    class TestIXor:
        def test_set(self) -> None:
            s = DAGSetView({1, 2, 3})
            s ^= {3, 4, 5}
            assert set(s) == {1, 2, 4, 5}

        def test_list(self) -> None:
            s = DAGSetView({1, 2})
            s ^= [2, 3]
            assert set(s) == {1, 3}

        def test_dagset(self) -> None:
            s = DAGSetView({1, 2, 3})
            other = DAGSetView({3, 4, 5})
            s ^= other
            assert set(s) == {1, 2, 4, 5}