+++ /dev/null
-// Copyright 2013 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.
-
-// This program takes an HTML file and outputs a corresponding article file in
-// present format. See: golang.org/x/tools/present
-package main // import "golang.org/x/tools/cmd/html2article"
-
-import (
- "bytes"
- "errors"
- "flag"
- "fmt"
- "io"
- "log"
- "net/url"
- "os"
- "regexp"
- "strings"
-
- "golang.org/x/net/html"
- "golang.org/x/net/html/atom"
-)
-
-func main() {
- flag.Parse()
-
- err := convert(os.Stdout, os.Stdin)
- if err != nil {
- log.Fatal(err)
- }
-}
-
-func convert(w io.Writer, r io.Reader) error {
- root, err := html.Parse(r)
- if err != nil {
- return err
- }
-
- style := find(root, isTag(atom.Style))
- if err := parseStyles(style); err != nil {
- log.Printf("couldn't parse all styles: %v", err)
- }
-
- body := find(root, isTag(atom.Body))
- if body == nil {
- return errors.New("couldn't find body")
- }
- article := limitNewlineRuns(makeHeadings(strings.TrimSpace(text(body))))
- _, err = fmt.Fprintf(w, "Title\n\n%s", article)
- return err
-}
-
-type Style string
-
-const (
- Bold Style = "*"
- Italic Style = "_"
- Code Style = "`"
-)
-
-var cssRules = make(map[string]Style)
-
-func parseStyles(style *html.Node) error {
- if style == nil || style.FirstChild == nil {
- return errors.New("couldn't find styles")
- }
-
- styles := style.FirstChild.Data
- readUntil := func(end rune) (string, bool) {
- i := strings.IndexRune(styles, end)
- if i < 0 {
- return "", false
- }
- s := styles[:i]
- styles = styles[i:]
- return s, true
- }
-
- for {
- sel, ok := readUntil('{')
- if !ok && sel == "" {
- break
- } else if !ok {
- return fmt.Errorf("could not parse selector %q", styles)
- }
-
- value, ok := readUntil('}')
- if !ok {
- return fmt.Errorf("couldn't parse style body for %s", sel)
- }
- switch {
- case strings.Contains(value, "italic"):
- cssRules[sel] = Italic
- case strings.Contains(value, "bold"):
- cssRules[sel] = Bold
- case strings.Contains(value, "Consolas") || strings.Contains(value, "Courier New"):
- cssRules[sel] = Code
- }
- }
- return nil
-}
-
-var newlineRun = regexp.MustCompile(`\n\n+`)
-
-func limitNewlineRuns(s string) string {
- return newlineRun.ReplaceAllString(s, "\n\n")
-}
-
-func makeHeadings(body string) string {
- buf := new(bytes.Buffer)
- lines := strings.Split(body, "\n")
- for i, s := range lines {
- if i == 0 && !isBoldTitle(s) {
- buf.WriteString("* Introduction\n\n")
- }
- if isBoldTitle(s) {
- s = strings.TrimSpace(strings.Replace(s, "*", " ", -1))
- s = "* " + s
- }
- buf.WriteString(s)
- buf.WriteByte('\n')
- }
- return buf.String()
-}
-
-func isBoldTitle(s string) bool {
- return !strings.Contains(s, " ") &&
- strings.HasPrefix(s, "*") &&
- strings.HasSuffix(s, "*")
-}
-
-func indent(buf *bytes.Buffer, s string) {
- for _, l := range strings.Split(s, "\n") {
- if l != "" {
- buf.WriteByte('\t')
- buf.WriteString(l)
- }
- buf.WriteByte('\n')
- }
-}
-
-func unwrap(buf *bytes.Buffer, s string) {
- var cont bool
- for _, l := range strings.Split(s, "\n") {
- l = strings.TrimSpace(l)
- if len(l) == 0 {
- if cont {
- buf.WriteByte('\n')
- buf.WriteByte('\n')
- }
- cont = false
- } else {
- if cont {
- buf.WriteByte(' ')
- }
- buf.WriteString(l)
- cont = true
- }
- }
-}
-
-func text(n *html.Node) string {
- var buf bytes.Buffer
- walk(n, func(n *html.Node) bool {
- switch n.Type {
- case html.TextNode:
- buf.WriteString(n.Data)
- return false
- case html.ElementNode:
- // no-op
- default:
- return true
- }
- a := n.DataAtom
- if a == atom.Span {
- switch {
- case hasStyle(Code)(n):
- a = atom.Code
- case hasStyle(Bold)(n):
- a = atom.B
- case hasStyle(Italic)(n):
- a = atom.I
- }
- }
- switch a {
- case atom.Br:
- buf.WriteByte('\n')
- case atom.P:
- unwrap(&buf, childText(n))
- buf.WriteString("\n\n")
- case atom.Li:
- buf.WriteString("- ")
- unwrap(&buf, childText(n))
- buf.WriteByte('\n')
- case atom.Pre:
- indent(&buf, childText(n))
- buf.WriteByte('\n')
- case atom.A:
- href, text := attr(n, "href"), childText(n)
- // Skip links with no text.
- if strings.TrimSpace(text) == "" {
- break
- }
- // Don't emit empty links.
- if strings.TrimSpace(href) == "" {
- buf.WriteString(text)
- break
- }
- // Use original url for Google Docs redirections.
- if u, err := url.Parse(href); err != nil {
- log.Printf("parsing url %q: %v", href, err)
- } else if u.Host == "www.google.com" && u.Path == "/url" {
- href = u.Query().Get("q")
- }
- fmt.Fprintf(&buf, "[[%s][%s]]", href, text)
- case atom.Code:
- buf.WriteString(highlight(n, "`"))
- case atom.B:
- buf.WriteString(highlight(n, "*"))
- case atom.I:
- buf.WriteString(highlight(n, "_"))
- case atom.Img:
- src := attr(n, "src")
- fmt.Fprintf(&buf, ".image %s\n", src)
- case atom.Iframe:
- src, w, h := attr(n, "src"), attr(n, "width"), attr(n, "height")
- fmt.Fprintf(&buf, "\n.iframe %s %s %s\n", src, h, w)
- case atom.Param:
- if attr(n, "name") == "movie" {
- // Old style YouTube embed.
- u := attr(n, "value")
- u = strings.Replace(u, "/v/", "/embed/", 1)
- if i := strings.Index(u, "&"); i >= 0 {
- u = u[:i]
- }
- fmt.Fprintf(&buf, "\n.iframe %s 540 304\n", u)
- }
- case atom.Title:
- default:
- return true
- }
- return false
- })
- return buf.String()
-}
-
-func childText(node *html.Node) string {
- var buf bytes.Buffer
- for n := node.FirstChild; n != nil; n = n.NextSibling {
- fmt.Fprint(&buf, text(n))
- }
- return buf.String()
-}
-
-func highlight(node *html.Node, char string) string {
- t := strings.Replace(childText(node), " ", char, -1)
- return fmt.Sprintf("%s%s%s", char, t, char)
-}
-
-type selector func(*html.Node) bool
-
-func isTag(a atom.Atom) selector {
- return func(n *html.Node) bool {
- return n.DataAtom == a
- }
-}
-
-func hasClass(name string) selector {
- return func(n *html.Node) bool {
- for _, a := range n.Attr {
- if a.Key == "class" {
- for _, c := range strings.Fields(a.Val) {
- if c == name {
- return true
- }
- }
- }
- }
- return false
- }
-}
-
-func hasStyle(s Style) selector {
- return func(n *html.Node) bool {
- for rule, s2 := range cssRules {
- if s2 != s {
- continue
- }
- if strings.HasPrefix(rule, ".") && hasClass(rule[1:])(n) {
- return true
- }
- if n.DataAtom.String() == rule {
- return true
- }
- }
- return false
- }
-}
-
-func attr(node *html.Node, key string) (value string) {
- for _, attr := range node.Attr {
- if attr.Key == key {
- return attr.Val
- }
- }
- return ""
-}
-
-func find(n *html.Node, fn selector) *html.Node {
- var result *html.Node
- walk(n, func(n *html.Node) bool {
- if result != nil {
- return false
- }
- if fn(n) {
- result = n
- return false
- }
- return true
- })
- return result
-}
-
-func walk(n *html.Node, fn selector) {
- if fn(n) {
- for c := n.FirstChild; c != nil; c = c.NextSibling {
- walk(c, fn)
- }
- }
-}
projects / dotfiles / .git / blobdiff