From a4bb5d703e4cb9d27e505c98049a0a27c85808f2 Mon Sep 17 00:00:00 2001
From: surdeus <surdeus@gmail.com>
Date: Thu, 23 Mar 2023 12:32:52 +0300
Subject: [PATCH] More flags standartization.

---
 .gitignore            |  1 +
 mkconfig              |  5 ++++
 mkfile                |  3 ++
 src/cmd/test/main.go  | 22 +++++++++------
 src/multitool/main.go | 65 +++++++++++++++++++++++++++++++++++++++----
 5 files changed, 82 insertions(+), 14 deletions(-)
 create mode 100644 .gitignore
 create mode 100644 mkconfig
 create mode 100644 mkfile

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..86daf54
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+exe
diff --git a/mkconfig b/mkconfig
new file mode 100644
index 0000000..b3be456
--- /dev/null
+++ b/mkconfig
@@ -0,0 +1,5 @@
+MKSHELL = sh
+<$(MKINCDIR)/config
+PKG_NAME = goblin
+CC = cc
+
diff --git a/mkfile b/mkfile
new file mode 100644
index 0000000..0c5baf7
--- /dev/null
+++ b/mkfile
@@ -0,0 +1,3 @@
+<mkconfig
+<$MKINCDIR/gobuild
+
diff --git a/src/cmd/test/main.go b/src/cmd/test/main.go
index d9832ac..b161302 100644
--- a/src/cmd/test/main.go
+++ b/src/cmd/test/main.go
@@ -1,31 +1,37 @@
 package main
 
 import(
-	"github.com/surdeus/gomtool/src/multitool"
+	mtool "github.com/surdeus/gomtool/src/multitool"
 	"strconv"
 	"fmt"
 )
 
 var(
-	tools = multitool.Tools{
-		"echo" : multitool.Tool{
-			func(args []string) {
-				fmt.Println(args)
+	tools = mtool.Tools{
+		"echo" : mtool.Tool{
+			func(args []string, flags *mtool.Flags) {
+				var b bool
+				flags.BoolVar(&b, "b", false, "the check flag")
+				flags.Parse(args)
+				fmt.Println(flags.Args())
 			},
 			"print string to standard output string",
+			"[str1 str2 ... strN]",
 		},
-		"sum" : multitool.Tool{
-			func(args []string) {
+		"sum" : mtool.Tool{
+			func(args []string, flags *mtool.Flags) {
+				flags.Parse(args)
 				one, _ := strconv.Atoi(args[1])
 				two, _ := strconv.Atoi(args[2])
 				fmt.Println(one + two)
 			},
 			"add one value to another",
+			"<int1> <int2>",
 		},
 	}
 )
 
 func main() {
-	multitool.Main("test", tools)
+	mtool.Main("test", tools)
 }
 
diff --git a/src/multitool/main.go b/src/multitool/main.go
index 3162ade..69ac86f 100644
--- a/src/multitool/main.go
+++ b/src/multitool/main.go
@@ -4,13 +4,19 @@ import(
 	"fmt"
 	"os"
 	path "path/filepath"
+	"flag"
 )
 
-type Tool struct {
-	Handler func(args []string)
-	Desc string
+type Flags struct {
+	*flag.FlagSet
 }
 
+type Handler func(args []string, flags *Flags)
+
+type Tool struct {
+	Handler Handler
+	Desc, Usage string
+}
 
 type Tools map[string] Tool
 
@@ -19,7 +25,9 @@ func Main(name string, m Tools) {
 		utilName string
 		args []string
 	)
-	binBase := path.Base(os.Args[0]) ;
+	
+	arg0 := os.Args[0]
+	binBase := path.Base(arg0) ;
 	binBase = binBase[:len(binBase)-len(path.Ext(binBase))]
 	if binBase != name {
 		utilName = binBase
@@ -36,10 +44,55 @@ func Main(name string, m Tools) {
 	}
 
 	if _, ok := m[utilName] ; !ok {
-		fmt.Printf("%s: No such uitl as '%s'.\n", os.Args[0], utilName )
+		fmt.Printf("%s: No such uitl as '%s'.\n", arg0, utilName )
 		os.Exit(1)
 	}
 
-	m[utilName].Handler(args)
+	util := m[utilName]
+	
+	arg1 := os.Args[1]
+	flagSet := flag.NewFlagSet(arg1, flag.ExitOnError)
+	flags := &Flags{
+		flagSet,
+	}
+	flags.Usage = func() {
+		out := flags.Output()
+		n := 0
+		flags.VisitAll(func(f *flag.Flag){
+			n++
+		})
+		
+		hasOptions := n != 0
+		
+		fmt.Fprintf(
+			out,
+			"Usage of %s:\n\t%s",
+			arg1, arg1,
+		)
+		if hasOptions {
+			fmt.Fprintf(out, " [options]")
+		}
+		
+		if util.Usage != "" {
+			fmt.Fprintf(
+				out,
+				" %s",
+				util.Usage,
+			)
+		}
+		
+		fmt.Fprintln(out, "")
+		
+		if hasOptions {
+			fmt.Fprintln(out, "Options:")
+			flags.PrintDefaults()
+		}
+		
+		os.Exit(1)
+	}
+	
+	args = args[1:]
+	
+	util.Handler(args, flags)
 }