# -*- coding: utf-8 -*-
from pandas import DataFrame, Series
from pandas_ta._typing import DictLike, Int
from pandas_ta.ma import ma
from pandas_ta.utils import v_mamode, v_offset, v_pos_default, v_series
from .long_run import long_run
from .short_run import short_run



def amat(
    close: Series, fast: Int = None, slow: Int = None,
    lookback: Int = None, mamode: str = None,
    offset: Int = None, **kwargs: DictLike
) -> DataFrame:
    """Archer Moving Averages Trends

    This indicator, by Kevin Johnson, attempts to identify both long run
    and short run trends.

    Sources:
        * Kevin Johnson
        * [tradingview](https://www.tradingview.com/script/Z2mq63fE-Trade-Archer-Moving-Averages-v1-4F/)

    Parameters:
        close (Series): ```close``` Series
        fast (int): Fast MA period. Default: ```8```
        slow (int): Slow MA period. Default: ```21```
        lookback (int): Lookback period for ```long_run``` and ```short_run```.
            Default: ```2```
        mamode (str): See ```help(ta.ma)```. Default: ```"ema"```
        offset (int): Post shift. Default: ```0```

    Other Parameters:
        run_length (int): OBV trend period. Default: ```2```
        fillna (value): ```pd.DataFrame.fillna(value)```

    Returns:
        (DataFrame): 2 columns

    Note:
        Both the long run and short run values are integers, where ```1```
        is a trend and ```0``` is not a trend.
    """
    # Validate
    fast = v_pos_default(fast, 8)
    slow = v_pos_default(slow, 21)
    lookback = v_pos_default(lookback, 2)
    close = v_series(close, max(fast, slow, lookback))

    if close is None:
        return

    mamode = v_mamode(mamode, "ema")
    offset = v_offset(offset)
    if "length" in kwargs:
        kwargs.pop("length")

    # Calculate
    fast_ma = ma(mamode, close, length=fast, **kwargs)
    slow_ma = ma(mamode, close, length=slow, **kwargs)

    mas_long = long_run(fast_ma, slow_ma, length=lookback)
    mas_short = short_run(fast_ma, slow_ma, length=lookback)

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

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

    _props = f"_{fast}_{slow}_{lookback}"
    data = {
        f"AMAT{mamode[0]}_LR{_props}": mas_long,
        f"AMAT{mamode[0]}_SR{_props}": mas_short
    }
    df = DataFrame(data, index=close.index)

    # Name and Category
    df.name = f"AMAT{mamode[0]}{_props}"
    df.category = "trend"

    return df