package views

import (
	"math"
	"strconv"

	g "maragu.dev/gomponents"
	. "maragu.dev/gomponents/html"
)

// transparentGIF is a 1x1 transparent GIF. It is the img fallback so the
// browser never shows a broken image while the source loads.
const transparentGIF = "data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7"

// Avatar renders a user avatar. A nil userID renders the placeholder.
// A nil version omits the cache-busting query parameter.
func Avatar(userID, version *int64, size int) g.Node {
	style := "width:" + strconv.Itoa(size) + "px;height:" + strconv.Itoa(size) + "px"
	if userID == nil {
		fontSize := int(math.Round(float64(size) * 0.45))
		return Span(Class("avatar avatar-placeholder"),
			Style(style+";font-size:"+strconv.Itoa(fontSize)+"px"),
			g.Text("?"))
	}
	src := "/avatars/" + strconv.FormatInt(*userID, 10) + ".png"
	if version != nil {
		src += "?v=" + strconv.FormatInt(*version, 10)
	}
	return Picture(Class("avatar"), Style(style),
		Source(SrcSet(src), Type("image/png")),
		Img(Src(transparentGIF), Alt(""), Width(strconv.Itoa(size)),
			Height(strconv.Itoa(size)), Class("avatar-img")),
	)
}