// Copyright 2015 The Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package linkify
import "unicode/utf8"
func atoi3(s string, start int) (int, bool) {
n := 0
var i int
for i = start; i < len(s) && digit(s[i]); i++ {
n = n*10 + int(s[i]-'0')
if n > 255 {
return 0, false
}
}
if i == start {
return 0, false
}
return i, true
}
func skipIPv4(s string) (_ int, _ bool) {
j := 0
for i := 0; i < 4; i++ {
if j >= len(s) {
return
}
if i > 0 {
if s[j] != '.' {
return
}
j++
}
n, ok := atoi3(s, j)
if !ok {
return
}
j = n
}
return j, true
}
func atoi5(s string, start int) (int, bool) {
n := 0
var i int
for i = start; i < len(s) && digit(s[i]); i++ {
n = n*10 + int(s[i]-'0')
if n > 65535 {
return 0, false
}
}
if i == start || n == 0 {
return 0, false
}
return i, true
}
func skipPort(s string, start int) int {
if start >= len(s) || s[start] != ':' {
return start
}
end, ok := atoi5(s, start+1)
if !ok {
return start
}
return end
}
func skipPath(s string, start int) int {
if start >= len(s) || s[start] != '/' {
return start // skip empty path
}
var stack []rune
var notClosedIndex int
var nHyphen int
end := start + 1
loop:
for end < len(s) {
r, rlen := utf8.DecodeRuneInString(s[end:])
if r == utf8.RuneError {
nHyphen = 0
break
}
switch {
case isUnreserved(r):
if r == '-' {
nHyphen++
if nHyphen > 1 {
break loop
}
} else {
nHyphen = 0
}
case isSubDelimiter(r) || r == '[' || r == ']':
nHyphen = 0
switch r {
case '[', '(':
if len(stack) == 0 {
notClosedIndex = end
}
stack = append(stack, r)
case ']', ')':
opening := '['
if r == ')' {
opening = '('
}
if len(stack) == 0 || stack[len(stack)-1] != opening {
break loop
}
stack = stack[:len(stack)-1]
}
case r == '/' || r == ':' || r == '@':
nHyphen = 0
case r == '%':
nHyphen = 0
if end+2 >= len(s) {
break loop
}
if !(hexDigit(s[end+1]) &&
hexDigit(s[end+2])) {
break loop
}
end += 2
default:
nHyphen = 0
if r != ' ' || len(stack) == 0 {
break loop
}
}
end += rlen
}
if len(stack) > 0 {
return notClosedIndex
}
if nHyphen > 0 {
return end - nHyphen + 1
}
return end
}
func skipQuery(s string, start int) int {
if start >= len(s) || s[start] != '?' {
return start
}
var stack []rune
var notClosedIndex int
var nHyphen int
end := start + 1
loop:
for end < len(s) {
r, rlen := utf8.DecodeRuneInString(s[end:])
if r == utf8.RuneError {
nHyphen = 0
break
}
switch {
case isUnreserved(r):
if r == '-' {
nHyphen++
if nHyphen > 1 {
break loop
}
} else {
nHyphen = 0
}
case isSubDelimiter(r) || r == '[' || r == ']':
nHyphen = 0
switch r {
case '[', '(':
if len(stack) == 0 {
notClosedIndex = end
}
stack = append(stack, r)
case ']', ')':
opening := '['
if r == ')' {
opening = '('
}
if len(stack) == 0 || stack[len(stack)-1] != opening {
break loop
}
stack = stack[:len(stack)-1]
}
case r == '?' || r == '/' || r == ':' || r == '@':
nHyphen = 0
case r == '%':
nHyphen = 0
if end+2 >= len(s) {
break loop
}
if !(hexDigit(s[end+1]) &&
hexDigit(s[end+2])) {
break loop
}
end += 2
default:
nHyphen = 0
if r != ' ' || len(stack) == 0 {
break loop
}
}
end += rlen
}
if len(stack) > 0 {
return notClosedIndex
}
if nHyphen > 0 {
return end - nHyphen + 1
}
return end
}
func skipFragment(s string, start int) int {
if start >= len(s) || s[start] != '#' {
return start
}
var stack []rune
var notClosedIndex int
var nHyphen int
end := start + 1
loop:
for end < len(s) {
r, rlen := utf8.DecodeRuneInString(s[end:])
if r == utf8.RuneError {
nHyphen = 0
break
}
switch {
case isUnreserved(r):
if r == '-' {
nHyphen++
if nHyphen > 1 {
break loop
}
} else {
nHyphen = 0
}
case isSubDelimiter(r) || r == '[' || r == ']':
nHyphen = 0
switch r {
case '[', '(':
if len(stack) == 0 {
notClosedIndex = end
}
stack = append(stack, r)
case ']', ')':
opening := '['
if r == ')' {
opening = '('
}
if len(stack) == 0 || stack[len(stack)-1] != opening {
break loop
}
stack = stack[:len(stack)-1]
}
case r == '?' || r == '/' || r == ':' || r == '@':
nHyphen = 0
case r == '%':
nHyphen = 0
if end+2 >= len(s) {
break loop
}
if !(hexDigit(s[end+1]) &&
hexDigit(s[end+2])) {
break loop
}
end += 2
default:
nHyphen = 0
if r != ' ' || len(stack) == 0 {
break loop
}
}
end += rlen
}
if len(stack) > 0 {
return notClosedIndex
}
if nHyphen > 0 {
return end - nHyphen + 1
}
return end
}
func unskipPunct(s string, start int) int {
end := start - 1
if end < 0 || end >= len(s) || !basicPunct[s[end]] {
return start
}
return end
}
func findHostnameStart(s string, start int) (_ int, _ bool) {
end := start
lastDot := true
nHyphen := 0
loop:
for end > 0 {
r, rlen := utf8.DecodeLastRuneInString(s[:end])
if r == utf8.RuneError {
return
}
switch {
case r == '.':
if nHyphen > 0 {
return
}
lastDot = true
case r == '-':
if end == start {
return
}
if lastDot {
return
}
nHyphen++
if nHyphen == 3 {
return
}
case r == ':' || r == '/' || r == '\\' || r == '_':
return
case isPunctOrSpaceOrControl(r):
break loop
default:
lastDot = false
nHyphen = 0
}
end -= rlen
}
if lastDot || nHyphen > 0 {
return
}
return end, true
}
func findHostnameEnd(s string, start int) (_ int, _ int, _ bool) {
end := start
lastDot := false
lastDotPos := -1
nHyphen := 0
loop:
for end < len(s) {
r, rlen := utf8.DecodeRuneInString(s[end:])
if r == utf8.RuneError {
return
}
switch {
case r == '.':
if nHyphen > 0 {
return
}
if lastDot {
break loop
}
lastDot = true
lastDotPos = end
nHyphen = 0
case r == '-':
lastDot = false
if end == start {
return
}
if lastDot {
return
}
nHyphen++
if nHyphen == 3 {
break loop
}
case r == '\\' || r == '_':
return
case isPunctOrSpaceOrControl(r):
break loop
default:
lastDot = false
nHyphen = 0
}
end += rlen
}
if nHyphen > 0 {
end -= nHyphen
} else if lastDot {
if s[end-1] == '.' {
end--
}
lastDotPos = end - 1
for lastDotPos >= start && s[lastDotPos] != '.' {
lastDotPos--
}
if lastDotPos < start {
lastDotPos = -1
}
}
return end, lastDotPos, true
}