Add support for virtual camera

This adds the following commands:

obs-cli virtualcam start
obs-cli virtualcam stop
obs-cli virtualcam toggle
obs-cli virtualcam status

Fixes #20.

README.md

@@ -216,3 +216,19 @@ Switch to a profile:
 ```
 obs-cli profile set <profile>
 ```
+
+### Virtual Camera
+
+Change the virtual camera state:
+
+```
+obs-cli virtualcam start
+obs-cli virtualcam stop
+obs-cli virtualcam toggle
+```
+
+Display virtual camera status:
+
+```
+obs-cli virtualcam status
+```

virtualcam.go

@@ -0,0 +1,87 @@
+package main
+
+import (
+	"fmt"
+	"strconv"
+
+	"github.com/spf13/cobra"
+)
+
+var (
+	virtualCamCmd = &cobra.Command{
+		Use:   "virtualcam",
+		Short: "manage virtual camera",
+		Long:  `The virtualcam command manages the virtual camera`,
+		RunE:  nil,
+	}
+
+	startStopVirtualCamCmd = &cobra.Command{
+		Use:   "toggle",
+		Short: "Toggle virtual camera status",
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return starStopVirtualCam()
+		},
+	}
+
+	startVirtualCamCmd = &cobra.Command{
+		Use:   "start",
+		Short: "Starts virtual camera",
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return startVirtualCam()
+		},
+	}
+
+	stopVirtualCamCmd = &cobra.Command{
+		Use:   "stop",
+		Short: "Stops virtual camera",
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return stopVirtualCam()
+		},
+	}
+
+	virtualCamStatusCmd = &cobra.Command{
+		Use:   "status",
+		Short: "Reports virtual camera status",
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return virtualCamStatus()
+		},
+	}
+)
+
+func starStopVirtualCam() error {
+	_, err := client.VirtualCam.StartStopVirtualCam()
+	return err
+}
+
+func startVirtualCam() error {
+	_, err := client.VirtualCam.StartVirtualCam()
+	return err
+}
+
+func stopVirtualCam() error {
+	_, err := client.VirtualCam.StopVirtualCam()
+	return err
+}
+
+func virtualCamStatus() error {
+	r, err := client.VirtualCam.GetVirtualCamStatus()
+	if err != nil {
+		return err
+	}
+
+	fmt.Printf("Virtual camera: %s\n", strconv.FormatBool(*r.IsVirtualCam))
+	if !*r.IsVirtualCam {
+		return nil
+	}
+
+	fmt.Printf("Timecode: %s\n", r.VirtualCamTimecode)
+	return nil
+}
+
+func init() {
+	virtualCamCmd.AddCommand(startStopVirtualCamCmd)
+	virtualCamCmd.AddCommand(startVirtualCamCmd)
+	virtualCamCmd.AddCommand(stopVirtualCamCmd)
+	virtualCamCmd.AddCommand(virtualCamStatusCmd)
+	rootCmd.AddCommand(virtualCamCmd)
+}