commit f3bfb03738e3f6e91260ee4ba6c98e8a63136b61
Author: nxshock <nxshock@gmail.com>
Date:   Wed Jun 30 18:35:00 2021 +0500

    Initial commit

diff --git a/.gitattributes b/.gitattributes
new file mode 100644
index 0000000..dfe0770
--- /dev/null
+++ b/.gitattributes
@@ -0,0 +1,2 @@
+# Auto detect text files and perform LF normalization
+* text=auto
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..f1c181e
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,12 @@
+# Binaries for programs and plugins
+*.exe
+*.exe~
+*.dll
+*.so
+*.dylib
+
+# Test binary, build with `go test -c`
+*.test
+
+# Output of the go coverage tool, specifically when used with LiteIDE
+*.out
diff --git a/LICENSE b/LICENSE
new file mode 100644
index 0000000..f9749a2
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2021 nxshock
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
diff --git a/progressmessage.go b/progressmessage.go
new file mode 100644
index 0000000..ddb3e87
--- /dev/null
+++ b/progressmessage.go
@@ -0,0 +1,118 @@
+package progressmessage
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"sync"
+	"time"
+)
+
+var (
+	defaultWriter           = os.Stderr
+	defaultUpdatePeriod     = time.Second
+	defaultMessageDelimiter = "\r"
+)
+
+type ProgressMessage struct {
+	// message format
+	format string
+
+	// list of message params
+	params []interface{}
+
+	// ticker for updating message
+	ticker *time.Ticker
+
+	// chan for stopping updates
+	stopChan chan struct{}
+
+	// previous message to prevent output of same message more than one time
+	prevMessage string
+
+	writer    io.Writer
+	isStarted bool
+
+	// message update period
+	updatePeriod time.Duration
+
+	mu sync.RWMutex
+}
+
+func New(format string) *ProgressMessage {
+	pm := &ProgressMessage{
+		format: format,
+
+		stopChan:     make(chan struct{}),
+		writer:       defaultWriter,
+		updatePeriod: defaultUpdatePeriod}
+
+	return pm
+}
+
+func (pm *ProgressMessage) ChangeWriter(newWriter io.Writer) {
+	pm.mu.Lock()
+	defer pm.mu.Unlock()
+
+	pm.writer = newWriter
+}
+
+func (pm *ProgressMessage) ChangeFormat(newFormat string) {
+	pm.mu.Lock()
+	defer pm.mu.Unlock()
+
+	pm.format = newFormat
+}
+
+func (pm *ProgressMessage) Update(params ...interface{}) {
+	// TODO: use mutex?
+
+	pm.params = params
+}
+
+func (pm *ProgressMessage) ChangeUpdatePeriod(newUpdatePeriod time.Duration) {
+	pm.mu.Lock()
+	defer pm.mu.Unlock()
+
+	if pm.isStarted {
+		defer func() {
+			pm.Stop()
+			pm.Start()
+		}()
+	}
+
+	pm.updatePeriod = newUpdatePeriod
+}
+
+func (pm *ProgressMessage) Start() {
+	pm.isStarted = true
+
+	go func() {
+		pm.ticker = time.NewTicker(pm.updatePeriod)
+
+		for {
+			select {
+			case <-pm.ticker.C:
+				if pm.params == nil {
+					continue
+				}
+
+				m := fmt.Sprintf(pm.format, pm.params...)
+				if m == pm.prevMessage {
+					continue
+				}
+				pm.writer.Write([]byte(defaultMessageDelimiter + m))
+				pm.prevMessage = m
+			case <-pm.stopChan:
+				pm.ticker.Stop()
+				break
+			}
+		}
+	}()
+}
+
+func (pm *ProgressMessage) Stop() {
+	pm.stopChan <- struct{}{}
+
+	pm.isStarted = false
+}