evdist: New project to handle settings programming

evdist/settings.go

@@ -0,0 +1,110 @@
+package main
+
+import (
+	"log"
+	"sync"
+	"time"
+
+	"srs.epita.fr/fic-server/settings"
+)
+
+// distList maintain a nextSettingsFile list up-to-date.
+type distList struct {
+	List  []*settings.NextSettingsFile
+	Lock  sync.RWMutex
+	Timer *time.Timer
+}
+
+// NewDistList creates a distList from the given src directory
+func NewDistList(src string) (*distList, error) {
+	list, err := settings.ListNextSettingsFiles()
+	if err != nil {
+		return nil, err
+	}
+	return &distList{List: list, Timer: time.NewTimer(time.Minute)}, nil
+}
+
+func (l *distList) TimerNextEvent() *time.Timer {
+	l.Lock.RLock()
+	defer l.Lock.RUnlock()
+
+	var min *time.Time
+
+	for _, f := range l.List {
+		if min == nil || f.Date.Before(*min) {
+			min = &f.Date
+		}
+	}
+
+	if min == nil {
+		return nil
+	}
+
+	if min == nil {
+		return nil
+	}
+
+	return time.NewTimer(time.Until(*min))
+}
+
+func (l *distList) AddEvent(nsf *settings.NextSettingsFile) {
+	l.Lock.Lock()
+
+	istop := len(l.List)
+	for i, n := range l.List {
+		if n.Id == nsf.Id {
+			return
+		} else if n.Date.After(nsf.Date) {
+			istop = i
+			break
+		}
+	}
+
+	l.List = append(l.List, nsf)
+	copy(l.List[istop+1:], l.List[istop:])
+	l.List[istop] = nsf
+
+	l.Lock.Unlock()
+
+	if istop == 0 {
+		l.ResetTimer()
+	}
+}
+
+func (l *distList) ResetTimer() {
+	l.Lock.RLock()
+	defer l.Lock.RUnlock()
+
+	if len(l.List) == 0 {
+		l.Timer.Reset(time.Minute)
+	} else {
+		l.Timer.Reset(time.Until(l.List[0].Date))
+	}
+}
+
+func (l *distList) Pop() *settings.NextSettingsFile {
+	l.Lock.Lock()
+	defer l.Lock.Unlock()
+
+	if len(l.List) == 0 {
+		return nil
+	}
+
+	if time.Now().Before(l.List[0].Date) {
+		return nil
+	}
+
+	ret := l.List[0]
+	l.List = l.List[1:]
+	return ret
+}
+
+func (l *distList) Print() {
+	l.Lock.RLock()
+	defer l.Lock.RUnlock()
+
+	log.Println("Seeing distlist")
+	for n, i := range l.List {
+		log.Printf("#%d: %v", n, *i)
+	}
+}