package nanoleaf

import (
	"encoding/binary"
	"time"
)

type panel struct {
	ID           uint16
	ColorRGBA    [4]byte
	TransitionAt time.Time

	O         int
	X         int
	Y         int
	ShapeType int

	Stale                bool
	SlowUpdates          int
	TicksUntilSlowUpdate int
}

func (p *panel) message() (message [8]byte) {
	transitionTime := p.TransitionAt.Sub(time.Now()).Round(time.Millisecond * 100)
	if transitionTime > maxTransitionTime {
		transitionTime = maxTransitionTime
	} else if transitionTime < 0 {
		transitionTime = 0
	}

	binary.BigEndian.PutUint16(message[0:], p.ID)
	copy(message[2:], p.ColorRGBA[:])
	binary.BigEndian.PutUint16(message[6:], uint16(transitionTime/(time.Millisecond*100)))

	return
}

func (p *panel) update(colorRGBA [4]byte, transitionAt time.Time) {
	if p.ColorRGBA != colorRGBA {
		p.ColorRGBA = colorRGBA
		p.Stale = true
		p.SlowUpdates = 3
		p.TicksUntilSlowUpdate = 10
	}
	p.TransitionAt = transitionAt
}

type panelUpdate []byte

func (u *panelUpdate) Add(message [8]byte) {
	if len(*u) < 2 {
		*u = make([]byte, 2, 10)
	}

	binary.BigEndian.PutUint16(*u, binary.BigEndian.Uint16(*u)+1)

	*u = append(*u, message[:]...)
}

func (u *panelUpdate) Len() int {
	if len(*u) < 2 {
		return 0
	}

	return int(binary.BigEndian.Uint16(*u))
}

const maxTransitionTime = time.Minute * 109