| // Copyright 2012 The Go 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 present |
| |
| import ( |
| "fmt" |
| "net/url" |
| "strings" |
| ) |
| |
| func init() { |
| Register("link", parseLink) |
| } |
| |
| type Link struct { |
| URL *url.URL |
| Label string |
| } |
| |
| func (l Link) TemplateName() string { return "link" } |
| |
| func parseLink(ctx *Context, fileName string, lineno int, text string) (Elem, error) { |
| args := strings.Fields(text) |
| url, err := url.Parse(args[1]) |
| if err != nil { |
| return nil, err |
| } |
| label := "" |
| if len(args) > 2 { |
| label = strings.Join(args[2:], " ") |
| } else { |
| scheme := url.Scheme + "://" |
| if url.Scheme == "mailto" { |
| scheme = "mailto:" |
| } |
| label = strings.Replace(url.String(), scheme, "", 1) |
| } |
| return Link{url, label}, nil |
| } |
| |
| func renderLink(url, text string) string { |
| text = font(text) |
| if text == "" { |
| text = url |
| } |
| return fmt.Sprintf(`<a href="%s" target="_blank">%s</a>`, url, text) |
| } |
| |
| // parseInlineLink parses an inline link at the start of s, and returns |
| // a rendered HTML link and the total length of the raw inline link. |
| // If no inline link is present, it returns all zeroes. |
| func parseInlineLink(s string) (link string, length int) { |
| if !strings.HasPrefix(s, "[[") { |
| return |
| } |
| end := strings.Index(s, "]]") |
| if end == -1 { |
| return |
| } |
| urlEnd := strings.Index(s, "]") |
| rawURL := s[2:urlEnd] |
| const badURLChars = `<>"{}|\^[] ` + "`" // per RFC2396 section 2.4.3 |
| if strings.ContainsAny(rawURL, badURLChars) { |
| return |
| } |
| if urlEnd == end { |
| simpleUrl := "" |
| url, err := url.Parse(rawURL) |
| if err == nil { |
| // If the URL is http://foo.com, drop the http:// |
| // In other words, render [[http://golang.org]] as: |
| // <a href="http://golang.org">golang.org</a> |
| if strings.HasPrefix(rawURL, url.Scheme+"://") { |
| simpleUrl = strings.TrimPrefix(rawURL, url.Scheme+"://") |
| } else if strings.HasPrefix(rawURL, url.Scheme+":") { |
| simpleUrl = strings.TrimPrefix(rawURL, url.Scheme+":") |
| } |
| } |
| return renderLink(rawURL, simpleUrl), end + 2 |
| } |
| if s[urlEnd:urlEnd+2] != "][" { |
| return |
| } |
| text := s[urlEnd+2 : end] |
| return renderLink(rawURL, text), end + 2 |
| } |