from dataclasses import dataclass, field

from hooked_containers import events as e
from hooked_containers.mapping import HookedMapping


@dataclass
class HookTracker:
    added: list[e.AddItemEvent] = field(default_factory=list)
    set: list[e.SetItemEvent] = field(default_factory=list)
    removed: list[e.RemoveItemEvent] = field(default_factory=list)

    def hook(self, event: e.ChangeEvent):
        match event:
            case e.AddItemEvent():
                self.added.append(event.item)
            case e.SetItemEvent():
                self.set.append(event.item)
            case e.RemoveItemEvent():
                self.removed.append(event.item)


class TestHookedMapping:
    class TestConstruction:
        def test_empty(self):
            m = HookedMapping({})
            assert m._data == {}
            assert dict(m) == {}

        def test_with_existing(self):
            existing = {"a": 1, "b": 2}
            og_id = id(existing)
            m = HookedMapping(existing)
            assert id(m._data) == og_id
            assert dict(m) == existing

        def test_nesting(self):
            existing = {"a": {"x": 1}, "b": {"y": 2}}
            m = HookedMapping(existing)
            assert dict(m) == existing
            assert dict(m["a"]) == {"x": 1}
            assert dict(m["b"]) == {"y": 2}

    class TestMappingOps:
        def test_setitem(self):
            tracker = HookTracker()
            m = HookedMapping({}, tracker.hook)
            m["a"] = 1
            assert m._data == {"a": 1}
            assert tracker.added == [1]

        def test_nested_setitem(self):
            tracker = HookTracker()
            m = HookedMapping({"a": {}}, tracker.hook)
            m["a"]["x"] = 1
            assert m._data == {"a": {"x": 1}}
            assert tracker.added == [1]

        def test_getitem(self):
            m = HookedMapping({"a": 1})
            assert m["a"] == 1

        def test_delitem(self):
            tracker = HookTracker()
            m = HookedMapping({"a": 1}, tracker.hook)
            del m["a"]
            assert not m["a"]
            assert tracker.removed == [1]