package generator

import (
	"path/filepath"
	"testing"
)

func TestWGPUSMPTEPattern(t *testing.T) {
	const width, height = 1920, 1080
	g, err := NewWGPUGenerator(width, height, filepath.Join("..", "..", "kernels", "static", "smpteBars.wgsl"))
	if err != nil {
		t.Fatalf("init: %v", err)
	}
	defer g.Close()

	buf := make([]byte, width*height*8/3)
	if err := g.GenerateFrame(buf, 0); err != nil {
		t.Fatalf("GenerateFrame: %v", err)
	}
	if err := g.GenerateFrame(buf, 1); err != nil {
		t.Fatalf("GenerateFrame 2: %v", err)
	}

	tests := []struct {
		name                  string
		x, y                  int
		wantY, wantCb, wantCr uint32
	}{
		{"top left gray flank", 100, 100, 414, 512, 512},
		{"top white bar", 300, 100, 721, 512, 512},
		{"top green bar", 960, 100, 534, 253, 207},
		{"top right gray flank", 1800, 100, 414, 512, 512},
		{"section 2 cyan flank", 100, 650, 754, 615, 64},
		{"section 2 minus I", 300, 650, 244, 612, 395},
		{"section 2 white", 600, 650, 721, 512, 512},
		{"section 2 blue flank", 1800, 650, 127, 960, 471},
		{"section 3 yellow flank", 100, 750, 877, 64, 553},
		{"section 3 plus Q", 300, 750, 141, 697, 606},
		{"section 3 red flank", 1800, 750, 250, 409, 960},
		{"bottom gray flank", 100, 900, 195, 512, 512},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			y, cb, cr := sampleV210(buf, width, tt.x, tt.y)
			if y != tt.wantY || cb != tt.wantCb || cr != tt.wantCr {
				t.Fatalf("pixel (%d,%d): got %d/%d/%d, want %d/%d/%d",
					tt.x, tt.y, y, cb, cr, tt.wantY, tt.wantCb, tt.wantCr)
			}
		})
	}
}