// Writes code blocks to the buffer.
func (self *Formatter) writeCodeBlock(node xml.Node) {
block := []byte(strings.Trim(node.Content(), "\n\r\v"))
node.SetContent("")
if len(block) == 0 {
return
}
self.buf.Write(block)
self.buf.Write([]byte{'\n', '\n'})
}
// Writes text blocks to the buffer.
func (self *Formatter) writeBlock(node xml.Node, prefix string) {
block := []byte(strings.TrimSpace(node.Content()))
node.SetContent("")
if len(block) == 0 {
return
}
// Position of last space, line break and max length.
sp, br, max := 0, 0, 79-len(prefix)
self.buf.WriteString(prefix)
for i, c := range block {
// Break line if exceeded max length and the position of the last space
// is greater than the position of the last line break. Don't break very
// long words.
if i-br > max && sp > br {
self.buf.WriteByte('\n')
br = sp
// Only the first line is prefixed.
for j := 0; j < len(prefix); j++ {
self.buf.WriteByte(' ')
}
}
if whitespace[c] {
// The last character was a space, so ignore this one.
if sp == i {
sp++
br++
continue
}
// Write the last word to the buffer, append a space and update
// the position of the last space.
if sp > br {
self.buf.WriteByte(' ')
}
self.buf.Write(block[sp:i])
sp = i + 1
}
}
// Write the last word to the buffer.
if sp < len(block) {
if sp > br {
self.buf.WriteByte(' ')
}
self.buf.Write(block[sp:])
}
// Close block with 2 breaks.
self.buf.Write([]byte{'\n', '\n'})
}
// Formats the content of inline elements and writes the content of block
// elements to the buffer.
func (self *Formatter) handleNode(node xml.Node) {
name := node.Name()
switch {
case ignore[name]:
// Remove ignored elements.
node.SetContent("")
case name == "pre":
// Treat pre elements as code blocks.
self.writeCodeBlock(node)
case heading[name]:
// Headings are prefixed with "# ".
self.writeBlock(node, "# ")
case name == "li":
// List items are prefixed with "- ".
self.writeBlock(node, "- ")
case name == "br":
// Preserve explicit line breaks.
node.SetContent("\n")
case italic[name]:
// Wrap italic elements with /.
node.SetContent("/" + node.Content() + "/")
case bold[name]:
// Wrap bold elements with *.
node.SetContent("*" + node.Content() + "*")
case name == "img":
// Collect the src of images and replace them with (alt)[url index]
alt, src := node.Attr("alt"), node.Attr("src")
if len(alt) > 0 && len(src) > 0 {
node.SetContent(fmt.Sprintf("(%s)[%d]", alt, len(self.links)))
self.links = append(self.links, src)
}
case name == "a":
// Collect the href and and the url index.
href, content := node.Attr("href"), node.Content()
if len(href) > 0 && len(content) > 0 {
node.SetContent(fmt.Sprintf("%s[%d]", content, len(self.links)))
self.links = append(self.links, href)
}
case block[name]:
// Write the content of block elements to the buffer.
self.writeBlock(node, "")
}
}
