import pytest
from src.history import HistoryManager, UISnapshot


class TestHistoryManager:
    def test_push_and_undo(self):
        hm = HistoryManager(max_capacity=10)
        hm.push({"value": 1}, "initial")
        hm.push({"value": 2}, "change to 2")
        assert hm.can_undo is True
        result = hm.undo(current_state={"value": 2})
        assert result is not None
        assert result.state["value"] == 2
        assert hm.can_undo is True

    def test_undo_and_redo(self):
        hm = HistoryManager(max_capacity=10)
        hm.push({"value": 1}, "initial")
        hm.push({"value": 2}, "change to 2")
        assert hm.can_redo is False
        hm.undo(current_state={"value": 2})
        assert hm.can_redo is True
        redone = hm.redo(current_state={"value": 1})
        assert redone is not None
        assert redone.state["value"] == 2

    def test_undo_no_history_returns_none(self):
        hm = HistoryManager(max_capacity=10)
        assert hm.can_undo is False
        result = hm.undo(current_state={"value": 1})
        assert result is None

    def test_redo_no_history_returns_none(self):
        hm = HistoryManager(max_capacity=10)
        assert hm.can_redo is False
        result = hm.redo(current_state={"value": 1})
        assert result is None

    def test_jump_to_undo(self):
        hm = HistoryManager(max_capacity=10)
        hm.push({"value": 1}, "initial")
        hm.push({"value": 2}, "change to 2")
        hm.push({"value": 3}, "change to 3")
        result = hm.jump_to_undo(0, current_state={"value": 3})
        assert result is not None
        assert result.state["value"] == 1
        assert hm.can_redo is True

    def test_get_history_returns_descriptions(self):
        hm = HistoryManager(max_capacity=10)
        hm.push({"value": 1}, "first")
        hm.push({"value": 2}, "second")
        hm.push({"value": 3}, "third")
        history = hm.get_history()
        assert len(history) == 3
        assert history[0]["description"] == "first"
        assert history[1]["description"] == "second"
        assert "timestamp" in history[0]

    def test_snapshot_roundtrip(self):
        snap = UISnapshot(
            ai_input="test input",
            project_system_prompt="project prompt",
            global_system_prompt="global prompt",
            base_system_prompt="base prompt",
            use_default_base_prompt=True,
            temperature=0.5,
            top_p=0.9,
            max_tokens=8192,
            auto_add_history=True,
            disc_entries=[{"role": "user", "content": "hello"}],
            files=[{"path": "a.txt"}],
            screenshots=["screenshot.png"],
        )
        d = snap.to_dict()
        restored = UISnapshot.from_dict(d)
        assert restored.ai_input == snap.ai_input
        assert restored.project_system_prompt == snap.project_system_prompt
        assert restored.global_system_prompt == snap.global_system_prompt
        assert restored.base_system_prompt == snap.base_system_prompt
        assert restored.use_default_base_prompt == snap.use_default_base_prompt
        assert restored.temperature == snap.temperature
        assert restored.top_p == snap.top_p
        assert restored.max_tokens == snap.max_tokens
        assert restored.auto_add_history == snap.auto_add_history
        assert restored.disc_entries == snap.disc_entries
        assert restored.files == snap.files
        assert restored.screenshots == snap.screenshots

    def test_push_clears_redo_stack(self):
        hm = HistoryManager(max_capacity=10)
        hm.push({"value": 1}, "initial")
        hm.push({"value": 2}, "change to 2")
        hm.undo(current_state={"value": 2})
        assert hm.can_redo is True
        hm.push({"value": 3}, "change to 3")
        assert hm.can_redo is False