From 4b23ef459808486c6c82e6b042f4e09c5f4fd0d1 Mon Sep 17 00:00:00 2001
From: Pavel <pashamullin202@gmail.com>
Date: Wed, 19 Jun 2024 17:29:20 +0300
Subject: [PATCH] reworked

---
 repository/statistics/click_statistics.go | 72 ++++++++++++++---------
 utils/binary_search.go                    | 20 +++++++
 2 files changed, 64 insertions(+), 28 deletions(-)
 create mode 100644 utils/binary_search.go

diff --git a/repository/statistics/click_statistics.go b/repository/statistics/click_statistics.go
index a786ea4..76c980c 100644
--- a/repository/statistics/click_statistics.go
+++ b/repository/statistics/click_statistics.go
@@ -4,6 +4,8 @@ import (
 	"context"
 	"database/sql"
 	"fmt"
+	"penahub.gitlab.yandexcloud.net/backend/quiz/common.git/utils"
+	"sort"
 	"strings"
 )
 
@@ -59,7 +61,6 @@ type Statistic struct {
 
 type PipeLineStatsResp [][]Statistic
 
-// todo нужно исключить множества из подмножеств, пока что получаются все уникальные векторы респондентов по опросу
 // пример:
 //"[0, 116783, 116810]"
 //"[0, 116783, 116798]"
@@ -69,27 +70,15 @@ type PipeLineStatsResp [][]Statistic
 //"[0, 116783]"
 //"[0, 116783, 116810, 116843]"
 
-//SELECT DISTINCT final FROM (
-//SELECT groupArray(ctxquestionid) AS final FROM (SELECT DISTINCT f.ctxsession, a.ctxquestionid
-//FROM (SELECT ctxsession, max(event_time) AS max_time
-//FROM statistics WHERE ctxquizid = 26276 GROUP BY ctxsession ) f
-//JOIN ( SELECT ctxsession, ctxquestionid, event_time
-//FROM statistics WHERE ctxquizid = 26276 ) a ON f.ctxsession = a.ctxsession)
-//GROUP BY ctxsession);
+//SELECT DISTINCT last_que, reversed
+//FROM ( SELECT groupArray(ctxquestionid) AS reversed, arraySlice(arrayReverse(groupArray(ctxquestionid)), 1, 1)[1] AS last_que
+//FROM statistics WHERE ctxquizid = 26276  GROUP BY ctxsession ) AS sub;
 
-func (s *StatisticClick) getFunnel(ctx context.Context, quizID int64, from uint64, to uint64) (map[int64][]string, error) {
-	// берем из матвью все что принадлежит quizID в указанном интервале времени
-	// выбираем самыые поздние по роу набер - 1
-	// группируем по ид вопроса и для каждого ид вопроса формируем массив сессий которые были последнимим для этого вопроса
-	// выбираем только те где длина массива = 1
+func (s *StatisticClick) getFunnel(ctx context.Context, quizID int64, from uint64, to uint64) (map[int64][]int64, error) {
 	query := `
-	SELECT ctxquestionid, arrayJoin(endsession) AS session
-	FROM (SELECT  ctxquestionid,   groupArray(ctxsession) AS endsession
-	    FROM (SELECT ctxsession,ctxquestionid,row_number() OVER (PARTITION BY ctxsession ORDER BY event_time DESC) AS row_num
-	        FROM mv_last_answers_events WHERE ctxquizid = ? AND event_time BETWEEN ? AND ?
-	    ) AS rows
-	    WHERE row_num = 1 GROUP BY ctxquestionid
-	) AS group_sessions WHERE length(endsession) = 1;
+	SELECT DISTINCT last_que, reversed
+	FROM ( SELECT groupArray(ctxquestionid) AS reversed, arraySlice(arrayReverse(groupArray(ctxquestionid)), 1, 1)[1] AS last_que
+         FROM statistics WHERE ctxquizid = ? AND event_time BETWEEN ? AND ?  GROUP BY ctxsession ) AS sub;
 	`
 
 	rows, err := s.conn.QueryContext(ctx, query, quizID, from, to)
@@ -98,23 +87,50 @@ func (s *StatisticClick) getFunnel(ctx context.Context, quizID int64, from uint6
 	}
 	defer rows.Close()
 
-	funnel := make(map[int64][]string)
-
+	funnel := make(map[int64][]int64)
 	for rows.Next() {
-		var questionID int64
-		var sessionID string
-		err := rows.Scan(&questionID, &sessionID)
-		if err != nil {
+		var lastQue int64
+		var reversed []int64
+		if err := rows.Scan(&lastQue, &reversed); err != nil {
 			return nil, err
 		}
-		funnel[questionID] = append(funnel[questionID], sessionID)
+		funnel[lastQue] = reversed
 	}
 
 	if err := rows.Err(); err != nil {
 		return nil, err
 	}
 
-	return funnel, nil
+	result := make(map[int64][]int64)
+	keys := make([]int64, 0, len(funnel))
+	for key := range funnel {
+		keys = append(keys, key)
+	}
+	sort.Slice(keys, func(i, j int) bool {
+		return keys[i] < keys[j]
+	})
+
+	for _, lastQue := range keys {
+		reversed := funnel[lastQue]
+		found := false
+
+		for _, otherLastQue := range keys {
+			if otherLastQue != lastQue {
+				otherReversed := funnel[otherLastQue]
+				index := utils.BinarySearch(lastQue, otherReversed)
+				if index {
+					found = true
+					break
+				}
+			}
+		}
+
+		if !found {
+			result[lastQue] = reversed
+		}
+	}
+
+	return result, nil
 }
 
 func (s *StatisticClick) GetPipelinesStatistics(ctx context.Context, quizID int64, from uint64, to uint64) (PipeLineStatsResp, error) {
diff --git a/utils/binary_search.go b/utils/binary_search.go
new file mode 100644
index 0000000..8e91039
--- /dev/null
+++ b/utils/binary_search.go
@@ -0,0 +1,20 @@
+package utils
+
+func BinarySearch(target int64, array []int64) bool {
+	left := 0
+	right := len(array) - 1
+
+	for left <= right {
+		mid := (left + right) / 2
+
+		if array[mid] == target {
+			return true
+		} else if array[mid] < target {
+			left = mid + 1
+		} else if array[mid] > target {
+			right = mid - 1
+		}
+	}
+
+	return false
+}