Implemented code blocks

Render.go

@@ -16,7 +16,9 @@ type renderer struct {
 	quoteLevel         int
 	listLevel          int
 	tableLevel         int
+	codeLines          int
 	tableHeaderWritten bool
+	inCodeBlock        bool
 }
 
 // Render creates HTML from the supplied markdown text.
@@ -52,6 +54,23 @@ func Render(markdown string) string {
 }
 
 func (r *renderer) processLine(line string) {
+	if r.inCodeBlock {
+		if strings.HasPrefix(line, "```") {
+			r.out.WriteString("</code></pre>")
+			r.inCodeBlock = false
+			r.codeLines = 0
+		} else {
+			if r.codeLines != 0 {
+				r.out.WriteByte('\n')
+			}
+
+			r.out.WriteString(html.EscapeString(line))
+			r.codeLines++
+		}
+
+		return
+	}
+
 	newQuoteLevel := 0
 
 	for strings.HasPrefix(line, ">") {
@@ -107,6 +126,25 @@ func (r *renderer) processLine(line string) {
 		r.out.WriteString("</li>")
 		return
 
+	case '`':
+		if strings.HasPrefix(line, "```") {
+			language := line[3:]
+
+			if !r.inCodeBlock {
+				if language != "" {
+					r.out.WriteString("<pre><code class=\"language-")
+					r.out.WriteString(html.EscapeString(language))
+					r.out.WriteString("\">")
+				} else {
+					r.out.WriteString("<pre><code>")
+				}
+
+				r.inCodeBlock = true
+			}
+
+			return
+		}
+
 	case '|':
 		r.closeParagraphs()
 		line = line[1:]