about summary refs log blame commit diff stats
path: root/widgets/spinner.go
blob: f49256aafefe6c91902a491f49e1c25b61d28e3c (plain) (tree)
1
2
3
4
5
6
7
8
9


               
                 
                     

              
                                     
 
                                         
                                         

 
                     
                        
                                         
                       
                            
                          

 
                                                   
                           


                                                                               
                                                              




                           



                          

                                      



                                      

                                                               

                                                                  
                                                            






                                              



                           

                            



                                    
                                               


                                         
                           
                         

         
                                                                     
 
                                                               
                                                     
                                                        

 
                                
                         
 
package widgets

import (
	"strings"
	"sync/atomic"
	"time"

	"github.com/gdamore/tcell/v2"

	"git.sr.ht/~sircmpwn/aerc/config"
	"git.sr.ht/~sircmpwn/aerc/lib/ui"
)

type Spinner struct {
	ui.Invalidatable
	frame  int64 // access via atomic
	frames []string
	stop   chan struct{}
	style  tcell.Style
}

func NewSpinner(uiConf *config.UIConfig) *Spinner {
	spinner := Spinner{
		stop:   make(chan struct{}),
		frame:  -1,
		frames: strings.Split(uiConf.Spinner, uiConf.SpinnerDelimiter),
		style:  uiConf.GetStyle(config.STYLE_SPINNER),
	}
	return &spinner
}

func (s *Spinner) Start() {
	if s.IsRunning() {
		return
	}

	atomic.StoreInt64(&s.frame, 0)

	go func() {
		for {
			select {
			case <-s.stop:
				atomic.StoreInt64(&s.frame, -1)
				s.stop <- struct{}{}
				return
			case <-time.After(200 * time.Millisecond):
				atomic.AddInt64(&s.frame, 1)
				s.Invalidate()
			}
		}
	}()
}

func (s *Spinner) Stop() {
	if !s.IsRunning() {
		return
	}

	s.stop <- struct{}{}
	<-s.stop
	s.Invalidate()
}

func (s *Spinner) IsRunning() bool {
	return atomic.LoadInt64(&s.frame) != -1
}

func (s *Spinner) Draw(ctx *ui.Context) {
	if !s.IsRunning() {
		s.Start()
	}

	cur := int(atomic.LoadInt64(&s.frame) % int64(len(s.frames)))

	ctx.Fill(0, 0, ctx.Width(), ctx.Height(), ' ', s.style)
	col := ctx.Width()/2 - len(s.frames[0])/2 + 1
	ctx.Printf(col, 0, s.style, "%s", s.frames[cur])
}

func (s *Spinner) Invalidate() {
	s.DoInvalidate(s)
}