From 25f168189c45c12cdc0b528d3800a15b9895f060 Mon Sep 17 00:00:00 2001
From: Nyan <git@nyan.su>
Date: Fri, 7 Jul 2023 16:35:00 +0300
Subject: [PATCH] initial commit

---
 autobuffer.go | 76 +++++++++++++++++++++++++++++++++++++++++++++++++++
 go.mod        |  3 ++
 2 files changed, 79 insertions(+)
 create mode 100644 autobuffer.go
 create mode 100644 go.mod

diff --git a/autobuffer.go b/autobuffer.go
new file mode 100644
index 0000000..1b50bf6
--- /dev/null
+++ b/autobuffer.go
@@ -0,0 +1,76 @@
+package autobuffer
+
+import (
+	"sync"
+)
+
+type Autobuffer[T any] struct {
+	size      int
+	buffer    []T
+	action    func(items []T)
+	inputChan chan T
+	flushChan chan bool
+	stopChan  chan bool
+	mu        *sync.Mutex
+}
+
+func New[T any](size int, action func(items []T)) *Autobuffer[T] {
+	x := &Autobuffer[T]{
+		size:      size,
+		buffer:    make([]T, 0),
+		action:    action,
+		inputChan: make(chan T),
+		flushChan: make(chan bool),
+		stopChan:  make(chan bool),
+		mu:        &sync.Mutex{},
+	}
+
+	go func() {
+		run := true
+		for run {
+			select {
+			case <-x.stopChan:
+				close(x.inputChan)
+				close(x.flushChan)
+				close(x.stopChan)
+				if len(x.buffer) > 0 {
+					x.mu.Lock()
+					old := x.buffer
+					x.buffer = make([]T, 0)
+					x.mu.Unlock()
+					action(old)
+				}
+				run = false
+			case <-x.flushChan:
+				x.mu.Lock()
+				old := x.buffer
+				x.buffer = make([]T, 0)
+				x.mu.Unlock()
+				action(old)
+			case item := <-x.inputChan:
+				x.mu.Lock()
+				x.buffer = append(x.buffer, item)
+				if len(x.buffer) >= x.size {
+					old := x.buffer
+					x.buffer = make([]T, 0)
+					action(old)
+				}
+				x.mu.Unlock()
+			}
+		}
+	}()
+
+	return x
+}
+
+func (ab Autobuffer[T]) Insert(item T) {
+	ab.inputChan <- item
+}
+
+func (ab *Autobuffer[T]) Flush() {
+	ab.flushChan <- true
+}
+
+func (ab *Autobuffer[T]) Stop() {
+	ab.stopChan <- true
+}
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..e94f703
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,3 @@
+module git.nyan.su/nyan/autobuffer
+
+go 1.20