package main

import (
	"fmt"
	"image"
	"image/color"
	"image/draw"
	"image/png"
	"os"
	"path/filepath"

	xdraw "golang.org/x/image/draw"
)

func writePNG(path string, img image.Image) {
	_ = os.MkdirAll(filepath.Dir(path), 0755)
	out, err := os.Create(path)
	if err != nil {
		panic(err)
	}
	defer out.Close()
	enc := png.Encoder{CompressionLevel: png.BestCompression}
	if err := enc.Encode(out, img); err != nil {
		panic(err)
	}
	fmt.Println("wrote", path)
}

func main() {
	root := `D:\vpn navi`
	srcPath := filepath.Join(root, "screen", "1.ru.png")
	f, err := os.Open(srcPath)
	if err != nil {
		panic(err)
	}
	src, err := png.Decode(f)
	f.Close()
	if err != nil {
		panic(err)
	}
	sb := src.Bounds()
	sw, sh := sb.Dx(), sb.Dy()
	side := sw
	if sh < side {
		side = sh
	}
	// Center crop to square — no stretch/distortion.
	ox := sb.Min.X + (sw-side)/2
	oy := sb.Min.Y + (sh-side)/2
	crop := image.NewRGBA(image.Rect(0, 0, side, side))
	draw.Draw(crop, crop.Bounds(), src, image.Pt(ox, oy), draw.Src)

	dst := image.NewRGBA(image.Rect(0, 0, 300, 300))
	xdraw.CatmullRom.Scale(dst, dst.Bounds(), crop, crop.Bounds(), xdraw.Over, nil)

	writePNG(filepath.Join(root, "screen", "1.ru.300x300.png"), dst)
	writePNG(filepath.Join(root, "dist", "microsoft-store", "listing", "screen", "1.ru.300x300.png"), dst)
	writePNG(filepath.Join(root, "packaging", "msix", "Assets", "StoreLogo300x300.png"), dst)

	// Padded fit (full frame, letterbox) — no crop.
	fit := image.NewRGBA(image.Rect(0, 0, 300, 300))
	draw.Draw(fit, fit.Bounds(), &image.Uniform{C: color.White}, image.Point{}, draw.Src)
	scale := float64(300) / float64(sw)
	if float64(sh)*scale > 300 {
		scale = float64(300) / float64(sh)
	}
	nw := int(float64(sw) * scale)
	nh := int(float64(sh) * scale)
	if nw < 1 {
		nw = 1
	}
	if nh < 1 {
		nh = 1
	}
	resized := image.NewRGBA(image.Rect(0, 0, nw, nh))
	xdraw.CatmullRom.Scale(resized, resized.Bounds(), src, sb, xdraw.Over, nil)
	off := image.Pt((300-nw)/2, (300-nh)/2)
	draw.Draw(fit, image.Rect(off.X, off.Y, off.X+nw, off.Y+nh), resized, image.Point{}, draw.Over)
	writePNG(filepath.Join(root, "screen", "1.ru.300x300.fit.png"), fit)

	fmt.Printf("source %dx%d -> crop %dx%d -> 300x300 (CatmullRom)\n", sw, sh, side, side)
}