1 files changed, 198 insertions, 0 deletions
diff --git a/Unicorn.go b/Unicorn.go
new file mode 100644
index 0000000..2e0e73f
--- /dev/null
+++ b/Unicorn.go
@@ -0,0 +1,198 @@
+package main
+
+import (
+	"github.com/veandco/go-sdl2/sdl"
+	// "golang.org/x/exp/io/spi"
+	// "github.com/veandco/go-sdl2/sdl"
+)
+
+// Unicorn ...
+// Object representing the Unicorn HAT to be controlled
+type Unicorn interface {
+	// Not all unicorns are the same size
+	GetWidth() uint8
+	GetHeight() uint8
+
+	// Array of pixels, indexed x, then y, then color (rgb)
+	GetPixels() [][][]uint8
+
+	// Set an individual pixel
+	SetPixel(x, y, r, g, b uint8)
+
+	// Flip the display buffer
+	Show()
+
+	// Set all pixels back to black
+	Clear()
+
+	// Turns off the LEDs
+	Off()
+}
+
+// GetUnicorn ...
+// Get a unicorn. Tries to get you a real one,
+// if it can't find one then gives you a fake one.
+func GetUnicorn() (unicorn Unicorn, err error) {
+	// unicorn, err = NewReal()
+	// if err != nil {
+	// 	log.Println("Couldn't get a real unicorn, trying a fake one")
+	// 	unicorn, err = NewFake(int8(16), int8(16))
+	// }
+	unicorn, err = NewFake(uint8(16), uint8(16))
+	return
+}
+
+// FakeUnicorn ...
+// Shows an SDL window pretending to be a unicorn.
+type FakeUnicorn struct {
+	pixels        [][][]uint8
+	displayWidth  int32
+	displayHeight int32
+
+	window   *sdl.Window
+	renderer *sdl.Renderer
+}
+
+// NewFake ...
+// Constructs a new fake unicorn out of paint and glue
+func NewFake(width, height uint8) (*FakeUnicorn, error) {
+	if err := sdl.Init(sdl.INIT_EVERYTHING); err != nil {
+		return nil, err
+	}
+
+	unicorn := &FakeUnicorn{
+		pixels:        makePixels(width, height),
+		window:        nil,
+		renderer:      nil,
+		displayWidth:  300,
+		displayHeight: 300,
+	}
+	if err := unicorn.createWindow(); err != nil {
+		unicorn.Close()
+		return nil, err
+	}
+	if err := unicorn.createRenderer(); err != nil {
+		unicorn.Close()
+		return nil, err
+	}
+	return unicorn, nil
+}
+
+func (f *FakeUnicorn) createWindow() error {
+	window, err := sdl.CreateWindow("Fake Unicorn",
+		sdl.WINDOWPOS_UNDEFINED,
+		sdl.WINDOWPOS_UNDEFINED,
+		f.displayWidth,
+		f.displayHeight,
+		sdl.WINDOW_SHOWN)
+	f.window = window
+	return err
+}
+
+func (f *FakeUnicorn) createRenderer() error {
+	renderer, err := sdl.CreateRenderer(f.window, -1, sdl.RENDERER_ACCELERATED)
+	f.renderer = renderer
+	return err
+}
+
+func (f *FakeUnicorn) Close() error {
+	if f.window != nil {
+		f.window.Destroy()
+	}
+	if f.renderer != nil {
+		f.renderer.Destroy()
+	}
+	return nil
+}
+
+func (f *FakeUnicorn) GetWidth() uint8 {
+	return uint8(len(f.pixels))
+}
+func (f *FakeUnicorn) GetHeight() uint8 {
+	if len(f.pixels) > 0 {
+		return uint8(len(f.pixels[0]))
+	}
+	return 0
+}
+func (f *FakeUnicorn) GetPixels() [][][]uint8 {
+	return f.pixels
+}
+func (f *FakeUnicorn) SetPixel(x, y, r, g, b uint8) {
+	f.pixels[x][y] = []uint8{r, g, b}
+}
+func (f *FakeUnicorn) Show() {
+	width, height := f.GetWidth(), f.GetHeight()
+	for x := uint8(0); x < width; x++ {
+		for y := uint8(0); y < height; y++ {
+			r, g, b := rgb(f.pixels[x][y])
+			if err := f.renderer.SetDrawColor(r, g, b, uint8(255)); err != nil {
+				panic(err)
+			}
+			cellWidth := f.displayWidth / int32(width)
+			cellHeight := f.displayHeight / int32(height)
+			if err := f.renderer.FillRect(&sdl.Rect{
+				X: cellWidth * int32(x),
+				Y: f.displayHeight - (cellHeight * int32(y)) - cellHeight, // SDL Y coordinate is from the top
+				W: cellWidth,
+				H: cellHeight,
+			}); err != nil {
+				panic(err)
+			}
+		}
+	}
+	f.renderer.Present()
+}
+
+func rgb(pixel []uint8) (uint8, uint8, uint8) {
+	return pixel[0], pixel[1], pixel[2]
+}
+
+func (f *FakeUnicorn) Clear() {
+	f.pixels = makePixels(f.GetWidth(), f.GetHeight())
+}
+func (f *FakeUnicorn) Off() {
+	f.Close()
+}
+
+func makePixels(width, height uint8) [][][]uint8 {
+	pixels := make([][][]uint8, width)
+	for x := uint8(0); x < width; x++ {
+		pixels[x] = make([][]uint8, height)
+		for y := uint8(0); y < height; y++ {
+			pixels[x][y] = []uint8{0, 0, 0}
+		}
+	}
+	return pixels
+}
+
+// RealUnicorn ...
+// A real one! *gasps*
+// type RealUnicorn struct {}
+
+// // NewReal ...
+// // Constructs a new real unicorn from fairy dust and sprinkles
+// func NewReal() (*RealUnicorn, error) {
+// 	return nil, errors.New("Couldn't make a real unicorn sorry")
+// }
+
+// func (u *RealUnicorn) GetWidth() int8 {
+// 	return 0
+// }
+// func (u *RealUnicorn) GetHeight() int8 {
+// 	return 0
+// }
+// func (u *RealUnicorn) GetPixels() [][][]int8 {
+// 	return nil
+// }
+// func (u *RealUnicorn) SetPixel(x, y, r, g, b int8) {
+
+// }
+// func (u *RealUnicorn) Show() {
+
+// }
+// func (u *RealUnicorn) Clear() {
+
+// }
+// func (u *RealUnicorn) Off() {
+
+// }