from collections.abc import Callable

from solo_tool.solo_tool import SoloTool

def changeSong(st: SoloTool, delta: int) -> Callable[[], None]:
    def f():
        if st.song is None:
            st.song = 0
        else:
            st.song += delta
    return f

def seekRelative(st: SoloTool, delta: float) -> Callable[[], None]:
    def f():
        st.position += delta
    return f

def positionToKeyPoint(st: SoloTool) -> Callable[[], None]:
    def f():
        st.keyPoint = st.position
    return f

def changeKeyPoint(st: SoloTool, delta: int) -> Callable[[], None]:
    from bisect import bisect_right, bisect_left
    def f():
        if delta > 0:
            pivot = bisect_right(st.keyPoints, st.keyPoint) - 1
        elif delta < 0:
            pivot = bisect_left(st.keyPoints, st.keyPoint) - 1
        else:
            return
        new = max(min(pivot + delta, len(st.keyPoints) - 1), 0)
        st.keyPoint = st.keyPoints[new]
    return f