cli: parse and resolve flags

Copy all flags from upstream. The machinectl flag is dropped as it does nothing. the flag package is used to reduce complexity since we do not care about compatibility with upstream.

Signed-off-by: Ophestra Umiker <cat@ophivana.moe>

4 files changed, 107 insertions, 0 deletions

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 00000000..ae08513c
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,25 @@
+# Binaries for programs and plugins
+*.exe
+*.exe~
+*.dll
+*.so
+*.dylib
+/ego
+
+# Test binary, built with `go test -c`
+*.test
+
+# Output of the go coverage tool, specifically when used with LiteIDE
+*.out
+
+# Dependency directories (remove the comment below to include it)
+# vendor/
+
+# Go workspace file
+go.work
+go.work.sum
+
+# env file
+.env
+.idea
+.vscode
\ No newline at end of file
diff --git a/cli.go b/cli.go
new file mode 100644
index 00000000..e85917e1
--- /dev/null
+++ b/cli.go
@@ -0,0 +1,67 @@
+package main
+
+import (
+	"errors"
+	"flag"
+	"fmt"
+	"os"
+	"os/user"
+)
+
+var (
+	ego     *user.User
+	command []string
+	verbose bool
+	method  = machinectl
+
+	userName     string
+	methodFlags  [2]bool
+	printVersion bool
+)
+
+const (
+	machinectl uint8 = iota
+	machinectlBare
+	sudo
+)
+
+func init() {
+	flag.StringVar(&userName, "u", "ego", "Specify a username")
+	flag.BoolVar(&methodFlags[0], "sudo", false, "Use 'sudo' to change user")
+	flag.BoolVar(&methodFlags[1], "bare", false, "Use 'machinectl' but skip xdg-desktop-portal setup")
+	flag.BoolVar(&verbose, "v", false, "Verbose output")
+	flag.BoolVar(&printVersion, "V", false, "Print version")
+}
+
+func copyArgs() {
+	if printVersion {
+		fmt.Println(Version)
+		os.Exit(0)
+	}
+
+	command = flag.Args()
+
+	switch { // zero value is machinectl
+	case methodFlags[0]:
+		method = sudo
+	case methodFlags[1]:
+		method = machinectlBare
+	}
+
+	if u, err := user.Lookup(userName); err != nil {
+		if errors.As(err, new(user.UnknownUserError)) {
+			fmt.Println("unknown user", userName)
+		} else {
+			// unreachable
+			panic(err)
+		}
+
+		os.Exit(1)
+	} else {
+		ego = u
+	}
+
+	if verbose {
+		fmt.Println("Running command", command, "as user", ego.Username, "("+ego.Uid+")")
+	}
+}
diff --git a/go.mod b/go.mod
new file mode 100644
index 00000000..c3d79715
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,3 @@
+module git.ophivana.moe/cat/ego
+
+go 1.22
diff --git a/main.go b/main.go
new file mode 100644
index 00000000..159d6d77
--- /dev/null
+++ b/main.go
@@ -0,0 +1,12 @@
+package main
+
+import (
+	"flag"
+)
+
+var Version = "impure"
+
+func main() {
+	flag.Parse()
+	copyArgs()
+}