package pandas

import "gitee.com/quant1x/pandas/stat"

func (self DataFrame) align(ss ...stat.Series) []stat.Series {
	defaultValue := []stat.Series{}
	sLen := len(ss)
	if sLen == 0 {
		return defaultValue
	}
	ls := make([]float32, sLen)
	for i, v := range ss {
		ls[i] = float32(v.Len())
	}

	maxLength := stat.Max(ls)
	if maxLength <= 0 {
		return defaultValue
	}
	cols := make([]stat.Series, sLen)
	for i, v := range ss {
		vt := v.Type()
		vn := v.Name()
		vs := v.Values()
		// 声明any的ns变量用于接收逻辑分支的输出
		// 切片数据不能直接对齐, 需要根据类型指定Nil和NaN默认值
		var ns any
		if vt == stat.SERIES_TYPE_BOOL {
			ns = stat.Align(vs.([]bool), stat.Nil2Bool, int(maxLength))
		} else if vt == stat.SERIES_TYPE_INT64 {
			ns = stat.Align(vs.([]int64), stat.Nil2Int64, int(maxLength))
		} else if vt == stat.SERIES_TYPE_STRING {
			ns = stat.Align(vs.([]string), stat.Nil2String, int(maxLength))
		} else if vt == stat.SERIES_TYPE_FLOAT32 {
			ns = stat.Align(vs.([]float32), stat.Nil2Float32, int(maxLength))
		} else if vt == stat.SERIES_TYPE_FLOAT64 {
			ns = stat.Align(vs.([]float64), stat.Nil2Float64, int(maxLength))
		}
		cols[i] = NewSeries(vt, vn, ns)
	}
	return cols
}

// Join 默认右连接, 加入一个series
func (self DataFrame) Join(series stat.Series) DataFrame {
	if series.Len() < 0 {
		return self
	}
	nCol := self.Ncol()
	cols := make([]stat.Series, nCol+1)
	cols[len(cols)-1] = series
	for i, s := range self.columns {
		cols[i] = s
	}
	cols = self.align(cols...)
	df := NewDataFrame(cols...)
	self = df
	return self
}