package led

import (
	"errors"
	"rpi-ci-led/pkg/ws2812b"
	"time"
)

type LEDSvc struct {
	pin   int
	count int
	blink map[int]chan struct{}
	done  chan struct{}
}

var led *LEDSvc

func Init(pin, count int) (*LEDSvc, error) {
	_, err := ws2812b.Init(pin, count, 255)
	if err != nil {
		return nil, err
	}
	return &LEDSvc{
		pin:   pin,
		count: count,
		blink: make(map[int]chan struct{}),
		done:  make(chan struct{}),
	}, nil
}

func Get() *LEDSvc {
	if led == nil {
		panic(errors.New("not init"))
	}
	return led
}

func (p *LEDSvc) Stop() {
	for k := range p.blink {
		p.StopBlink(k)
	}

	ws2812b.ClearAll()

	close(p.done)
}

func (p *LEDSvc) SetColor(pos int, color uint32) error {
	if pos < 0 || pos > p.count {
		return errors.New("out of range")
	}
	if ch, ok := p.blink[pos]; ok {
		close(ch)
		delete(p.blink, pos)
	}
	ws2812b.WriteColor(pos, color)
	return nil
}

func (p *LEDSvc) StopBlink(pos int) {
	if ch, ok := p.blink[pos]; ok {
		close(ch)
		delete(p.blink, pos)
	}
}

func (p *LEDSvc) SetBlink(pos int, color uint32, interval time.Duration) {
	if ch, ok := p.blink[pos]; ok {
		close(ch)
		delete(p.blink, pos)
	}
	go func() {
		defer func() {
			ws2812b.WriteColor(pos, 0)
			delete(p.blink, pos)
		}()

		ch := make(chan struct{})
		p.blink[pos] = ch
		timer := time.NewTicker(interval)
		on := false
		for {
			select {
			case <-ch:
				return
			case <-timer.C:
				if on {
					ws2812b.WriteColor(pos, 0)
				} else {
					ws2812b.WriteColor(pos, color)
				}
				on = !on
			}
		}
	}()
}

func (p *LEDSvc) Run() {
	ticker := time.NewTicker(time.Millisecond * 100)
	for {
		select {
		case <-p.done:
			return
		case <-ticker.C:
		}
	}
}