Change docker context to default in MacOS during machine start

Fixes: #1654

Signed-off-by: vyasgun <vyasgun20@gmail.com>

cmd/podman/machine/start.go

@@ -5,6 +5,11 @@ package machine
 
 import (
 	"fmt"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"runtime"
+	"strings"
 
 	"github.com/containers/podman/v4/cmd/podman/registry"
 	"github.com/containers/podman/v4/libpod/events"
@@ -79,7 +84,36 @@ func start(_ *cobra.Command, args []string) error {
 	if err := vm.Start(vmName, startOpts); err != nil {
 		return err
 	}
+	if err := changeDockerContext(); err != nil {
+		fmt.Fprintf(os.Stderr, "Failed to change docker context to default. Error: %v\n", err)
+	} else {
+		fmt.Fprintf(os.Stderr, "Docker context has been set to default\n")
+	}
 	fmt.Printf("Machine %q started successfully\n", vmName)
 	newMachineEvent(events.Start, events.Event{Name: vmName})
 	return nil
 }
+
+func changeDockerContext() error {
+	if runtime.GOOS != "darwin" {
+		return nil
+	}
+	pathList := strings.Split(os.Getenv("PATH"), ":")
+	var dockerBinaryPath string
+	for _, path := range pathList {
+		dockerPath := filepath.Join(path, "docker")
+		if info, err := os.Stat(dockerPath); err == nil && info.Mode().IsRegular() {
+			dockerBinaryPath = dockerPath
+			break
+		}
+	}
+	if dockerBinaryPath == "" {
+		return fmt.Errorf("docker binary not found")
+	}
+
+	cmd := exec.Command(dockerBinaryPath, "context", "use", "default")
+
+	// Run the command
+	_, err := cmd.CombinedOutput()
+	return err
+}