# -*- coding: utf-8 -*-
from pandas import Series
from pandas_ta._typing import DictLike, Int
from pandas_ta.maps import Imports
from pandas_ta.utils import v_offset, v_pos_default, v_series, v_talib



def midpoint(
    close: Series, length: Int = None, talib: bool = None,
    offset: Int = None, **kwargs: DictLike
) -> Series:
    """Midpoint

    The Midpoint is the average of the rolling high and low of period length.

    Parameters:
        close (Series): ```close``` Series
        length (int): The period. Default: ```2```
        talib (bool): If installed, use TA Lib. Default: ```True```
        offset (int): Post shift. Default: ```0```

    Other Parameters:
        fillna (value): ```pd.DataFrame.fillna(value)```

    Returns:
        (Series): 1 column
    """
    # Validate
    length = v_pos_default(length, 2)
    if "min_periods" in kwargs and kwargs["min_periods"] is not None:
        min_periods = int(kwargs["min_periods"])
    else:
        min_periods = length
    close = v_series(close, max(length, min_periods))

    if close is None:
        return

    mode_tal = v_talib(talib)
    offset = v_offset(offset)

    # Calculate
    if Imports["talib"] and mode_tal:
        from talib import MIDPOINT
        midpoint = MIDPOINT(close, length)
    else:
        lowest = close.rolling(length, min_periods=min_periods).min()
        highest = close.rolling(length, min_periods=min_periods).max()
        midpoint = 0.5 * (lowest + highest)

    # Offset
    if offset != 0:
        midpoint = midpoint.shift(offset)

    # Fill
    if "fillna" in kwargs:
        midpoint.fillna(kwargs["fillna"], inplace=True)

    # Name and Category
    midpoint.name = f"MIDPOINT_{length}"
    midpoint.category = "overlap"

    return midpoint