"""Tests for draggable tab functionality."""

import json
import pytest

from development_hub.draggable_tab_widget import (
    DraggableTabBar,
    DraggableTabWidget,
    TAB_MIME_TYPE,
)


class TestDraggableTabBar:
    """Tests for DraggableTabBar."""

    def test_create_with_pane_id(self, qtbot):
        """Tab bar stores pane ID."""
        bar = DraggableTabBar("test-pane-123")
        qtbot.addWidget(bar)
        assert bar.pane_id == "test-pane-123"

    def test_accepts_drops(self, qtbot):
        """Tab bar accepts drops."""
        bar = DraggableTabBar("test")
        qtbot.addWidget(bar)
        assert bar.acceptDrops() == True


class TestDraggableTabWidget:
    """Tests for DraggableTabWidget."""

    def test_create_with_pane_id(self, qtbot):
        """Tab widget stores pane ID."""
        widget = DraggableTabWidget(pane_id="my-pane")
        qtbot.addWidget(widget)
        assert widget.pane_id == "my-pane"

    def test_auto_generates_pane_id(self, qtbot):
        """Tab widget auto-generates pane ID if not provided."""
        widget = DraggableTabWidget()
        qtbot.addWidget(widget)
        assert widget.pane_id is not None
        assert len(widget.pane_id) > 0

    def test_pane_id_setter(self, qtbot):
        """Pane ID can be set after creation."""
        widget = DraggableTabWidget()
        qtbot.addWidget(widget)
        widget.pane_id = "new-pane-id"
        assert widget.pane_id == "new-pane-id"

    def test_accepts_drops(self, qtbot):
        """Tab widget accepts drops."""
        widget = DraggableTabWidget()
        qtbot.addWidget(widget)
        assert widget.acceptDrops() == True

    def test_tabs_closable(self, qtbot):
        """Tabs are closable."""
        widget = DraggableTabWidget()
        qtbot.addWidget(widget)
        assert widget.tabsClosable() == True

    def test_tabs_movable(self, qtbot):
        """Tabs are movable."""
        widget = DraggableTabWidget()
        qtbot.addWidget(widget)
        assert widget.isMovable() == True

    def test_drop_index_empty(self, qtbot):
        """Drop index at end when no tabs."""
        widget = DraggableTabWidget()
        qtbot.addWidget(widget)
        from PySide6.QtCore import QPoint
        index = widget._get_drop_index(QPoint(0, 0))
        assert index == 0

    def test_custom_tab_bar(self, qtbot):
        """Uses custom DraggableTabBar."""
        widget = DraggableTabWidget(pane_id="test")
        qtbot.addWidget(widget)
        assert isinstance(widget.tabBar(), DraggableTabBar)
        assert widget.tabBar().pane_id == "test"


class TestMimeData:
    """Tests for MIME data format."""

    def test_mime_type_constant(self):
        """MIME type constant is defined."""
        assert TAB_MIME_TYPE == "application/x-devhub-tab"

    def test_drag_data_format(self):
        """Drag data includes required fields."""
        data = {
            "pane_id": "source-pane",
            "tab_index": 2,
            "tab_text": "Terminal",
        }
        encoded = json.dumps(data).encode('utf-8')
        decoded = json.loads(encoded.decode('utf-8'))

        assert decoded["pane_id"] == "source-pane"
        assert decoded["tab_index"] == 2
        assert decoded["tab_text"] == "Terminal"


class TestPaneWidgetTabOperations:
    """Tests for PaneWidget tab operations used in cross-pane drag."""

    def test_take_tab_at_valid_index(self, qtbot):
        """take_tab_at removes and returns tab at index."""
        from PySide6.QtWidgets import QLabel

        from development_hub.pane_widget import PaneWidget

        pane = PaneWidget()
        qtbot.addWidget(pane)

        # Add some tabs
        label1 = QLabel("Tab 1")
        label2 = QLabel("Tab 2")
        pane.tab_widget.addTab(label1, "First")
        pane.tab_widget.addTab(label2, "Second")

        assert pane.tab_count() == 2

        result = pane.take_tab_at(0)
        assert result is not None
        widget, title = result
        assert title == "First"
        assert pane.tab_count() == 1

    def test_take_tab_at_invalid_index(self, qtbot):
        """take_tab_at returns None for invalid index."""
        from development_hub.pane_widget import PaneWidget

        pane = PaneWidget()
        qtbot.addWidget(pane)

        result = pane.take_tab_at(99)
        assert result is None

        result = pane.take_tab_at(-1)
        assert result is None

    def test_insert_widget_tab(self, qtbot):
        """insert_widget_tab inserts at correct position."""
        from PySide6.QtWidgets import QLabel

        from development_hub.pane_widget import PaneWidget

        pane = PaneWidget()
        qtbot.addWidget(pane)

        label1 = QLabel("Tab 1")
        label2 = QLabel("Tab 2")
        label3 = QLabel("Tab 3")

        pane.tab_widget.addTab(label1, "First")
        pane.tab_widget.addTab(label2, "Second")

        # Insert in middle
        pane.insert_widget_tab(1, label3, "Inserted")

        assert pane.tab_count() == 3
        assert pane.tab_widget.tabText(0) == "First"
        assert pane.tab_widget.tabText(1) == "Inserted"
        assert pane.tab_widget.tabText(2) == "Second"

    def test_pane_has_unique_id(self, qtbot):
        """Each pane has a unique ID."""
        from development_hub.pane_widget import PaneWidget

        pane1 = PaneWidget()
        pane2 = PaneWidget()
        qtbot.addWidget(pane1)
        qtbot.addWidget(pane2)

        assert pane1.pane_id != pane2.pane_id
        assert len(pane1.pane_id) > 0
        assert len(pane2.pane_id) > 0


class TestWorkspaceTabDropHandling:
    """Tests for workspace manager tab drop handling."""

    def test_find_pane_by_id(self, qtbot):
        """Workspace can find pane by ID."""
        from development_hub.workspace_manager import WorkspaceManager

        manager = WorkspaceManager()
        qtbot.addWidget(manager)

        panes = manager.find_panes()
        assert len(panes) == 1

        pane = panes[0]
        found = manager._find_pane_by_id(pane.pane_id)
        assert found == pane

    def test_find_pane_by_id_not_found(self, qtbot):
        """Returns None for unknown pane ID."""
        from development_hub.workspace_manager import WorkspaceManager

        manager = WorkspaceManager()
        qtbot.addWidget(manager)

        found = manager._find_pane_by_id("nonexistent-id")
        assert found is None


if __name__ == "__main__":
    pytest.main([__file__, "-v"])