1// Copyright © 2013 Steve Francia <spf@spf13.com>.
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6// http://www.apache.org/licenses/LICENSE-2.0
7//
8// Unless required by applicable law or agreed to in writing, software
9// distributed under the License is distributed on an "AS IS" BASIS,
10// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
11// See the License for the specific language governing permissions and
12// limitations under the License.
13
14// Commands similar to git, go tools and other modern CLI tools
15// inspired by go, go-Commander, gh and subcommand
16
17package cobra
18
19import (
20	"fmt"
21	"io"
22	"reflect"
23	"strconv"
24	"strings"
25	"text/template"
26	"time"
27	"unicode"
28)
29
30var templateFuncs = template.FuncMap{
31	"trim":                    strings.TrimSpace,
32	"trimRightSpace":          trimRightSpace,
33	"trimTrailingWhitespaces": trimRightSpace,
34	"appendIfNotPresent":      appendIfNotPresent,
35	"rpad":                    rpad,
36	"gt":                      Gt,
37	"eq":                      Eq,
38}
39
40var initializers []func()
41
42// EnablePrefixMatching allows to set automatic prefix matching. Automatic prefix matching can be a dangerous thing
43// to automatically enable in CLI tools.
44// Set this to true to enable it.
45var EnablePrefixMatching = false
46
47// EnableCommandSorting controls sorting of the slice of commands, which is turned on by default.
48// To disable sorting, set it to false.
49var EnableCommandSorting = true
50
51// MousetrapHelpText enables an information splash screen on Windows
52// if the CLI is started from explorer.exe.
53// To disable the mousetrap, just set this variable to blank string ("").
54// Works only on Microsoft Windows.
55var MousetrapHelpText = `This is a command line tool.
56
57You need to open cmd.exe and run it from there.
58`
59
60// MousetrapDisplayDuration controls how long the MousetrapHelpText message is displayed on Windows
61// if the CLI is started from explorer.exe. Set to 0 to wait for the return key to be pressed.
62// To disable the mousetrap, just set MousetrapHelpText to blank string ("").
63// Works only on Microsoft Windows.
64var MousetrapDisplayDuration = 5 * time.Second
65
66// AddTemplateFunc adds a template function that's available to Usage and Help
67// template generation.
68func AddTemplateFunc(name string, tmplFunc interface{}) {
69	templateFuncs[name] = tmplFunc
70}
71
72// AddTemplateFuncs adds multiple template functions that are available to Usage and
73// Help template generation.
74func AddTemplateFuncs(tmplFuncs template.FuncMap) {
75	for k, v := range tmplFuncs {
76		templateFuncs[k] = v
77	}
78}
79
80// OnInitialize sets the passed functions to be run when each command's
81// Execute method is called.
82func OnInitialize(y ...func()) {
83	initializers = append(initializers, y...)
84}
85
86// FIXME Gt is unused by cobra and should be removed in a version 2. It exists only for compatibility with users of cobra.
87
88// Gt takes two types and checks whether the first type is greater than the second. In case of types Arrays, Chans,
89// Maps and Slices, Gt will compare their lengths. Ints are compared directly while strings are first parsed as
90// ints and then compared.
91func Gt(a interface{}, b interface{}) bool {
92	var left, right int64
93	av := reflect.ValueOf(a)
94
95	switch av.Kind() {
96	case reflect.Array, reflect.Chan, reflect.Map, reflect.Slice:
97		left = int64(av.Len())
98	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
99		left = av.Int()
100	case reflect.String:
101		left, _ = strconv.ParseInt(av.String(), 10, 64)
102	}
103
104	bv := reflect.ValueOf(b)
105
106	switch bv.Kind() {
107	case reflect.Array, reflect.Chan, reflect.Map, reflect.Slice:
108		right = int64(bv.Len())
109	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
110		right = bv.Int()
111	case reflect.String:
112		right, _ = strconv.ParseInt(bv.String(), 10, 64)
113	}
114
115	return left > right
116}
117
118// FIXME Eq is unused by cobra and should be removed in a version 2. It exists only for compatibility with users of cobra.
119
120// Eq takes two types and checks whether they are equal. Supported types are int and string. Unsupported types will panic.
121func Eq(a interface{}, b interface{}) bool {
122	av := reflect.ValueOf(a)
123	bv := reflect.ValueOf(b)
124
125	switch av.Kind() {
126	case reflect.Array, reflect.Chan, reflect.Map, reflect.Slice:
127		panic("Eq called on unsupported type")
128	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
129		return av.Int() == bv.Int()
130	case reflect.String:
131		return av.String() == bv.String()
132	}
133	return false
134}
135
136func trimRightSpace(s string) string {
137	return strings.TrimRightFunc(s, unicode.IsSpace)
138}
139
140// FIXME appendIfNotPresent is unused by cobra and should be removed in a version 2. It exists only for compatibility with users of cobra.
141
142// appendIfNotPresent will append stringToAppend to the end of s, but only if it's not yet present in s.
143func appendIfNotPresent(s, stringToAppend string) string {
144	if strings.Contains(s, stringToAppend) {
145		return s
146	}
147	return s + " " + stringToAppend
148}
149
150// rpad adds padding to the right of a string.
151func rpad(s string, padding int) string {
152	template := fmt.Sprintf("%%-%ds", padding)
153	return fmt.Sprintf(template, s)
154}
155
156// tmpl executes the given template text on data, writing the result to w.
157func tmpl(w io.Writer, text string, data interface{}) error {
158	t := template.New("top")
159	t.Funcs(templateFuncs)
160	template.Must(t.Parse(text))
161	return t.Execute(w, data)
162}
163
164// ld compares two strings and returns the levenshtein distance between them.
165func ld(s, t string, ignoreCase bool) int {
166	if ignoreCase {
167		s = strings.ToLower(s)
168		t = strings.ToLower(t)
169	}
170	d := make([][]int, len(s)+1)
171	for i := range d {
172		d[i] = make([]int, len(t)+1)
173	}
174	for i := range d {
175		d[i][0] = i
176	}
177	for j := range d[0] {
178		d[0][j] = j
179	}
180	for j := 1; j <= len(t); j++ {
181		for i := 1; i <= len(s); i++ {
182			if s[i-1] == t[j-1] {
183				d[i][j] = d[i-1][j-1]
184			} else {
185				min := d[i-1][j]
186				if d[i][j-1] < min {
187					min = d[i][j-1]
188				}
189				if d[i-1][j-1] < min {
190					min = d[i-1][j-1]
191				}
192				d[i][j] = min + 1
193			}
194		}
195
196	}
197	return d[len(s)][len(t)]
198}
199
200func stringInSlice(a string, list []string) bool {
201	for _, b := range list {
202		if b == a {
203			return true
204		}
205	}
206	return false
207}
208