Add /invite command

telegram/commands.go

@@ -3,6 +3,7 @@ package telegram
 import (
 	"fmt"
 	"github.com/pkg/errors"
+	"math"
 	"regexp"
 	"strconv"
 	"strings"
@@ -443,6 +444,37 @@ func (c *Client) ProcessChatCommand(chatID int64, cmdline string) (string, bool)
 				return err.Error(), true
 			}
 		}
+	// invite @username to current groupchat
+	case "invite":
+		if len(args) < 1 {
+			return notEnoughArguments, true
+		}
+
+		if chatID < 0 {
+			userID, err := strconv.ParseInt(args[0], 10, 32)
+			// couldn't parse the id, try to lookup as a username
+			if err != nil {
+				chat, err := c.client.SearchPublicChat(&client.SearchPublicChatRequest{
+					Username: args[0],
+				})
+				if err != nil {
+					return err.Error(), true
+				}
+
+				userID = chat.Id
+				if userID <= 0 || userID > math.MaxInt32 {
+					return "Not a user", true
+				}
+			}
+
+			_, err = c.client.AddChatMember(&client.AddChatMemberRequest{
+				ChatId: chatID,
+				UserId: int32(userID),
+			})
+			if err != nil {
+				return err.Error(), true
+			}
+		}
 	case "help":
 		return helpString(helpTypeChat), true
 	default: