From 09c91ccbe49e772ecf5a54cd7a9ebeaf695d4946 Mon Sep 17 00:00:00 2001
From: Alexander Zobnin <alexanderzobnin@gmail.com>
Date: Thu, 23 Sep 2021 17:44:02 +0300
Subject: [PATCH] Fix top() and bottom() functions by fixing sorting, closes
 #1313

---
 pkg/timeseries/models.go |  3 +++
 pkg/timeseries/sort.go   | 11 +++++------
 2 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/pkg/timeseries/models.go b/pkg/timeseries/models.go
index 26b60c2..0b84dd7 100644
--- a/pkg/timeseries/models.go
+++ b/pkg/timeseries/models.go
@@ -49,6 +49,9 @@ type TimeSeriesMeta struct {
 
 	// Item update interval. nil means not supported intervals (flexible, schedule, etc)
 	Interval *time.Duration
+
+	// AggValue is using for sorting purposes
+	AggValue *float64
 }
 
 type AggFunc = func(points []TimePoint) *float64
diff --git a/pkg/timeseries/sort.go b/pkg/timeseries/sort.go
index 4220ba8..0358bf8 100644
--- a/pkg/timeseries/sort.go
+++ b/pkg/timeseries/sort.go
@@ -7,16 +7,15 @@ import (
 
 // SortBy sorts series by value calculated with provided aggFunc in given order
 func SortBy(series []*TimeSeriesData, order string, aggFunc AggFunc) []*TimeSeriesData {
-	aggregatedSeries := make([]TimeSeries, len(series))
-	for i, s := range series {
-		aggregatedSeries[i] = s.TS.GroupByRange(aggFunc)
+	for _, s := range series {
+		s.Meta.AggValue = aggFunc(s.TS)
 	}
 
 	// Sort by aggregated value
 	sort.Slice(series, func(i, j int) bool {
-		if len(aggregatedSeries[i]) > 0 && len(aggregatedSeries[j]) > 0 {
-			return *aggregatedSeries[i][0].Value < *aggregatedSeries[j][0].Value
-		} else if len(aggregatedSeries[j]) > 0 {
+		if series[i].Meta.AggValue != nil && series[j].Meta.AggValue != nil {
+			return *series[i].Meta.AggValue < *series[j].Meta.AggValue
+		} else if series[j].Meta.AggValue != nil {
 			return true
 		}
 		return false