from __future__ import annotations

from dpg_map.commands import CommandKind, MapCommand
from dpg_map.renderer import drain_renderer_commands
from dpg_map.state import DirtyFlags, create_map_state


def test_renderer_command_drain_preserves_structural_order_and_coalesces() -> None:
    state = create_map_state(tag="renderer-drain")
    state.dirty = DirtyFlags.NONE

    state.command_queue.put(MapCommand(CommandKind.ADD_OVERLAY, state.tag, {"tag": "a"}))
    state.command_queue.put(MapCommand(CommandKind.SET_VIEW, state.tag, {"zoom": 3}))
    state.command_queue.put(MapCommand(CommandKind.SET_VIEW, state.tag, {"zoom": 4}))
    state.command_queue.put(MapCommand(CommandKind.UPDATE_OVERLAY, state.tag, {"tag": "a", "v": 1}))
    state.command_queue.put(MapCommand(CommandKind.UPDATE_OVERLAY, state.tag, {"tag": "a", "v": 2}))
    state.command_queue.put(MapCommand(CommandKind.DELETE_OVERLAY, state.tag, {"tag": "a"}))

    commands = drain_renderer_commands(state)

    assert [command.kind for command in commands] == [
        CommandKind.ADD_OVERLAY,
        CommandKind.SET_VIEW,
        CommandKind.UPDATE_OVERLAY,
        CommandKind.DELETE_OVERLAY,
    ]
    assert commands[1].payload == {"zoom": 4}
    assert commands[2].payload == {"tag": "a", "v": 2}
    assert state.dirty & DirtyFlags.VIEW
    assert state.dirty & DirtyFlags.OVERLAYS