1 files changed, 92 insertions, 0 deletions
diff --git a/go/cmd/gitlab-shell/command/command.go b/go/cmd/gitlab-shell/command/command.go
new file mode 100644
index 0000000..c35a685
--- /dev/null
+++ b/go/cmd/gitlab-shell/command/command.go
@@ -0,0 +1,92 @@
+package command
+
+import (
+	"os"
+	"regexp"
+	"strconv"
+)
+
+type CommandType string
+
+const (
+	Discover CommandType = "discover"
+)
+
+type Command struct {
+	GitlabUsername string
+	GitlabKeyId    int
+	SshConnection  bool
+	Command        string
+	Type           CommandType
+}
+
+func New(arguments []string) (*Command, error) {
+	_, sshConnection := os.LookupEnv("SSH_CONNECTION")
+
+	command := &Command{SshConnection: sshConnection}
+
+	if _, err := parseWho(arguments, command); err != nil {
+		return nil, err
+	}
+
+	originalCommand, _ := os.LookupEnv("SSH_ORIGINAL_COMMAND")
+	parseCommand(originalCommand, command)
+
+	return command, nil
+}
+
+func parseWho(arguments []string, command *Command) (*Command, error) {
+	var err error = nil
+
+	for _, argument := range arguments {
+		keyId, err := tryParseKeyId(argument)
+		if keyId > 0 && err != nil {
+			command.GitlabKeyId = keyId
+			break
+		}
+
+		username, err := tryParseUsername(argument)
+		if username != "" && err != nil {
+			command.GitlabUsername = username
+			break
+		}
+	}
+
+	return command, err
+}
+
+func tryParseKeyId(argument string) (int, error) {
+	whoKeyRegex, err := regexp.Compile(`\bkey-(?P<keyid>\d+)\b`)
+	if err != nil {
+		return 0, err
+	}
+
+	keyMatch := whoKeyRegex.FindString(argument)
+	if keyMatch != "" {
+		gitlabKeyId, err := strconv.Atoi(keyMatch)
+
+		return gitlabKeyId, err
+	}
+
+	return 0, nil
+}
+
+func tryParseUsername(argument string) (string, error) {
+	whoUsernameRegex, err := regexp.Compile(`\busername-(?P<username>\S+)\b`)
+	if err != nil {
+		return "", err
+	}
+
+	usernameMatch := whoUsernameRegex.FindString(argument)
+	return usernameMatch, nil
+}
+
+func parseCommand(commandString string, command *Command) *Command {
+	command.Command = commandString
+
+	if commandString == "" {
+		command.Type = Discover
+	}
+
+	return nil
+}