From 081c6cf95ca49743d3666cafdd2ac83c73cc4186 Mon Sep 17 00:00:00 2001
From: Marcel Otte <otte.mm@googlemail.com>
Date: Tue, 2 Nov 2021 14:36:07 +0100
Subject: [PATCH] Scheduler first steps

---
 scheduler/scheduler.go | 41 +++++++++++++++++++++++++++++++++++++----
 1 file changed, 37 insertions(+), 4 deletions(-)

diff --git a/scheduler/scheduler.go b/scheduler/scheduler.go
index 1dd2b1b..5021647 100644
--- a/scheduler/scheduler.go
+++ b/scheduler/scheduler.go
@@ -1,15 +1,21 @@
 package scheduler
 
 import (
+	"container/list"
 	"encoding/json"
+	"fmt"
 	"time"
 
 	"github.com/qwc/backive/config"
 	"github.com/qwc/backive/db"
 )
 
+type backupRuns struct {
+	runlist *list.List
+}
+
 // Runs contains the Data for the scheduler: mapping from backups to a list of timestamps of the last 10 backups
-type Runs map[string][]time.Time
+type Runs map[string]backupRuns
 
 var runs Runs
 
@@ -27,7 +33,6 @@ func Save() {
 	if err != nil {
 		panic(err)
 	}
-
 	db.Database["runs"] = string(str)
 }
 
@@ -36,9 +41,37 @@ func ShouldRun(backup string) bool {
 	backupdata := config.Get().Backups[backup]
 	freq := backupdata.Frequency
 	// calculate time difference from last run, return true if no run has taken place
-	if freq > 0 {
+	lr, ok := LastRun(backup)
+	if ok == nil {
+		dur := time.Since(lr)
+		days := dur.Hours() / 24
+		if days > float64(freq) {
+			return true
+		}
+	}
+	if freq == 0 {
 		return true
 	}
-
 	return false
 }
+
+// RegisterRun saves a date of a backup run into the internal storage
+func RegisterRun(backup string) {
+	nbl, ok := runs[backup]
+	if !ok {
+		nbl.runlist = list.New()
+		runs[backup] = nbl
+	}
+	nbl.runlist.PushFront(time.Now())
+}
+
+// LastRun returns the time.Time of the last run of the backup given.
+func LastRun(backup string) (time.Time, error) {
+	_, ok := runs[backup]
+	if ok {
+		var t = time.Time(runs[backup].runlist.Front().Value.(time.Time))
+		return t, nil
+	} else {
+		return time.Unix(0, 0), fmt.Errorf("Backup name not found and therefore has never run!")
+	}
+}