from __future__ import annotations

import pytest

import dpg_map as dpgm
from dpg_map.commands import CommandKind
from dpg_map.interaction import (
    calculate_hit_rect,
    handle_mouse_down,
    handle_mouse_drag,
    handle_mouse_release,
    handle_mouse_wheel,
    pan_state_by_pixels,
)
from dpg_map.sizing import SizeMeasurement, apply_size_measurement
from dpg_map.state import DirtyFlags, create_map_state, get_map_state


def test_hit_rect_uses_effective_map_size() -> None:
    state = create_map_state(tag="hit-rect")
    apply_size_measurement(state, SizeMeasurement(width=400, height=250, visible=True))

    rect = calculate_hit_rect(state, (10.0, 20.0))

    assert rect.x == 10.0
    assert rect.y == 20.0
    assert rect.width == 400
    assert rect.height == 250
    assert rect.contains(410.0, 270.0)
    assert not rect.contains(411.0, 270.0)


def test_pan_updates_center_and_queues_view_command() -> None:
    state = create_map_state(tag="pan", center=(0.0, 0.0), zoom=3)
    apply_size_measurement(state, SizeMeasurement(width=400, height=300, visible=True))

    old_center = state.center
    pan_state_by_pixels(state, 40.0, 0.0)

    assert state.center != old_center
    assert state.center[1] < old_center[1]
    assert state.dirty & DirtyFlags.VIEW
    drained = state.command_queue.drain()
    assert drained[-1].kind is CommandKind.SET_VIEW
    assert drained[-1].payload["center"] == state.center


def test_mouse_drag_uses_active_drag_state() -> None:
    state = create_map_state(tag="drag", center=(0.0, 0.0), zoom=3)
    apply_size_measurement(state, SizeMeasurement(width=400, height=300, visible=True))
    rect = calculate_hit_rect(state, (10.0, 20.0))

    handle_mouse_down(state, (20.0, 30.0), rect)
    assert state.interaction.active_drag is True
    handle_mouse_drag(state, (45.0, 30.0))
    handle_mouse_release(state)

    assert state.interaction.active_drag is False
    assert state.interaction.last_mouse_position is None
    assert state.center[1] < 0.0


def test_wheel_zoom_keeps_cursor_latlon_stable() -> None:
    state = create_map_state(tag="wheel", center=(47.9029, 1.9093), zoom=8)
    apply_size_measurement(state, SizeMeasurement(width=800, height=600, visible=True))
    rect = calculate_hit_rect(state, (100.0, 50.0))

    before = dpgm.screen_to_latlon(300.0, 200.0, map_tag="wheel")
    handle_mouse_wheel(state, mouse_pos=(400.0, 250.0), wheel_delta=1.0, hit_rect=rect)
    after = dpgm.screen_to_latlon(300.0, 200.0, map_tag="wheel")

    assert state.zoom == 9
    assert after == pytest.approx(before, abs=1e-7)


def test_view_coordinate_helpers_roundtrip() -> None:
    create_map_state(tag="view-roundtrip", center=(47.9029, 1.9093), zoom=12)
    state = get_map_state("view-roundtrip")
    apply_size_measurement(state, SizeMeasurement(width=800, height=600, visible=True))

    screen = dpgm.latlon_to_screen(47.91, 1.92, map_tag="view-roundtrip")
    latlon = dpgm.screen_to_latlon(*screen, map_tag="view-roundtrip")

    assert latlon == pytest.approx((47.91, 1.92), abs=1e-7)


def test_fit_bounds_sets_center_and_zoom() -> None:
    create_map_state(tag="fit", center=(0.0, 0.0), zoom=2)
    state = get_map_state("fit")
    apply_size_measurement(state, SizeMeasurement(width=800, height=600, visible=True))

    dpgm.fit_bounds(((47.8, 1.8), (48.0, 2.0)), map_tag="fit")

    assert dpgm.get_center(map_tag="fit") == pytest.approx((47.9, 1.9))
    assert dpgm.get_zoom(map_tag="fit") > 2