42wim/matterbridge

package btelegram

import (
    "bytes"

    "github.com/russross/blackfriday"
)

type customHTML struct {
    blackfriday.Renderer
}

func (options *customHTML) Paragraph(out *bytes.Buffer, text func() bool) {
    marker := out.Len()

    if !text() {
        out.Truncate(marker)
        return
    }
    out.WriteString("\n")
}

func (options *customHTML) BlockCode(out *bytes.Buffer, text []byte, lang string) {
    out.WriteString("<pre>")

    out.WriteString(string(text))
    out.WriteString("</pre>\n")
}

func (options *customHTML) CodeSpan(out *bytes.Buffer, text []byte) {
    out.WriteString("<code>")
    out.WriteString(string(text))
    out.WriteString("</code>")
}

func (options *customHTML) Header(out *bytes.Buffer, text func() bool, level int, id string) {
    options.Paragraph(out, text)
}

func (options *customHTML) HRule(out *bytes.Buffer) {
    out.WriteByte('\n') //nolint:errcheck
}

func (options *customHTML) BlockQuote(out *bytes.Buffer, text []byte) {
    out.WriteString("> ")
    out.Write(text)
    out.WriteByte('\n')
}

func (options *customHTML) LineBreak(out *bytes.Buffer) {
    out.WriteByte('\n')
}

func (options *customHTML) List(out *bytes.Buffer, text func() bool, flags int) {
    options.Paragraph(out, text)
}

func (options *customHTML) ListItem(out *bytes.Buffer, text []byte, flags int) {
    out.WriteString("- ")
    out.Write(text)
    out.WriteByte('\n')
}

func makeHTML(input string) string {
    return string(blackfriday.Markdown([]byte(input),
        &customHTML{blackfriday.HtmlRenderer(blackfriday.HTML_USE_XHTML|blackfriday.HTML_SKIP_IMAGES, "", "")},
        blackfriday.EXTENSION_NO_INTRA_EMPHASIS|
            blackfriday.EXTENSION_FENCED_CODE|
            blackfriday.EXTENSION_AUTOLINK|
            blackfriday.EXTENSION_SPACE_HEADERS|
            blackfriday.EXTENSION_HEADER_IDS|
            blackfriday.EXTENSION_BACKSLASH_LINE_BREAK|
            blackfriday.EXTENSION_DEFINITION_LISTS))
}