add help

1 files changed, 54 insertions, 0 deletions

diff --git a/pkg/server/cmds.go b/pkg/server/cmds.go
index f148991..e383dac 100644
--- a/pkg/server/cmds.go
+++ b/pkg/server/cmds.go
@@ -2,6 +2,7 @@ package server
 
 import (
 	"strings"
+	"sort"
 	"log"
 )
 
@@ -17,6 +18,10 @@ type node struct {
 
 var cmds = newNode()
 
+func init() {
+	newCmd(help, "help")
+}
+
 func newNode() *node {
 	return &node{m: map[string]*node{}}
 }
@@ -61,3 +66,52 @@ func getCmd(path []string) (*cmd, []string) {
 
 	return nil, nil
 }
+
+func help(r *request) {
+	var ss []string
+
+	var walker func ([]string, *node)
+
+	walker = func (path []string, node *node) {
+		if node.c != nil {
+			ss = append(ss, strings.Join(path, " "))
+			return
+		}
+
+		n := len(path)
+		path = append(path, "")
+
+		for k, v := range node.m {
+			path[n] = k
+			walker(path, v)
+		}
+	}
+
+	root := cmds
+
+	for _, s := range r.args {
+		root = root.m[s]
+
+		if root == nil {
+			break
+		}
+	}
+
+	if root == nil {
+		r.Print("nothing to help")
+		return
+	}
+
+	if root.c != nil {
+		r.Print("usage: ", root.c.name, " [...]")
+		return
+	}
+
+	walker(nil, root)
+
+	sort.Strings(ss)
+
+	for _, s := range ss {
+		r.Println(s)
+	}
+}