Begin refactoring gui

This begins a big refactor of moving more code out of the Gui struct into contexts, controllers, and helpers. We also move some code into structs in the
gui package purely for the sake of better encapsulation

pkg/gui/controllers/helpers/snake_helper.go

@@ -0,0 +1,76 @@
+package helpers
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/jesseduffield/lazygit/pkg/gui/style"
+	"github.com/jesseduffield/lazygit/pkg/gui/types"
+	"github.com/jesseduffield/lazygit/pkg/snake"
+)
+
+type SnakeHelper struct {
+	c    *types.HelperCommon
+	game *snake.Game
+}
+
+func NewSnakeHelper(c *types.HelperCommon) *SnakeHelper {
+	return &SnakeHelper{
+		c: c,
+	}
+}
+
+func (self *SnakeHelper) StartGame() {
+	view := self.c.Views().Snake
+
+	game := snake.NewGame(view.Width(), view.Height(), self.renderSnakeGame, self.c.LogAction)
+	self.game = game
+	game.Start()
+}
+
+func (self *SnakeHelper) ExitGame() {
+	self.game.Exit()
+}
+
+func (self *SnakeHelper) SetDirection(direction snake.Direction) {
+	self.game.SetDirection(direction)
+}
+
+func (self *SnakeHelper) renderSnakeGame(cells [][]snake.CellType, alive bool) {
+	view := self.c.Views().Snake
+
+	if !alive {
+		_ = self.c.ErrorMsg(self.c.Tr.YouDied)
+		return
+	}
+
+	output := self.drawSnakeGame(cells)
+
+	view.Clear()
+	fmt.Fprint(view, output)
+	self.c.Render()
+}
+
+func (self *SnakeHelper) drawSnakeGame(cells [][]snake.CellType) string {
+	writer := &strings.Builder{}
+
+	for i, row := range cells {
+		for _, cell := range row {
+			switch cell {
+			case snake.None:
+				writer.WriteString(" ")
+			case snake.Snake:
+				writer.WriteString("█")
+			case snake.Food:
+				writer.WriteString(style.FgMagenta.Sprint("█"))
+			}
+		}
+
+		if i < len(cells) {
+			writer.WriteString("\n")
+		}
+	}
+
+	output := writer.String()
+	return output
+}