Formatting: Do not use \n and prefer <br> instead

It moves bbcode to bbcode_pleroma as the former is owned by kaniini
and transfering ownership wasn't done in a timely manner.

Closes: https://git.pleroma.social/pleroma/pleroma/issues/1374
Closes: https://git.pleroma.social/pleroma/pleroma/issues/1375

2 files changed, 257 insertions, 1 deletions

diff --git a/lib/pleroma/earmark_renderer.ex b/lib/pleroma/earmark_renderer.ex
new file mode 100644
index 000000000..6211a3b4a
--- /dev/null
+++ b/lib/pleroma/earmark_renderer.ex
@@ -0,0 +1,256 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2020 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+#
+# This file is derived from Earmark, under the following copyright:
+# Copyright © 2014 Dave Thomas, The Pragmatic Programmers
+# SPDX-License-Identifier: Apache-2.0
+# Upstream: https://github.com/pragdave/earmark/blob/master/lib/earmark/html_renderer.ex
+defmodule Pleroma.EarmarkRenderer do
+  @moduledoc false
+
+  alias Earmark.Block
+  alias Earmark.Context
+  alias Earmark.HtmlRenderer
+  alias Earmark.Options
+
+  import Earmark.Inline, only: [convert: 3]
+  import Earmark.Helpers.HtmlHelpers
+  import Earmark.Message, only: [add_messages_from: 2, get_messages: 1, set_messages: 2]
+  import Earmark.Context, only: [append: 2, set_value: 2]
+  import Earmark.Options, only: [get_mapper: 1]
+
+  @doc false
+  def render(blocks, %Context{options: %Options{}} = context) do
+    messages = get_messages(context)
+
+    {contexts, html} =
+      get_mapper(context.options).(
+        blocks,
+        &render_block(&1, put_in(context.options.messages, []))
+      )
+      |> Enum.unzip()
+
+    all_messages =
+      contexts
+      |> Enum.reduce(messages, fn ctx, messages1 -> messages1 ++ get_messages(ctx) end)
+
+    {put_in(context.options.messages, all_messages), html |> IO.iodata_to_binary()}
+  end
+
+  #############
+  # Paragraph #
+  #############
+  defp render_block(%Block.Para{lnb: lnb, lines: lines, attrs: attrs}, context) do
+    lines = convert(lines, lnb, context)
+    add_attrs(lines, "<p>#{lines.value}</p>", attrs, [], lnb)
+  end
+
+  ########
+  # Html #
+  ########
+  defp render_block(%Block.Html{html: html}, context) do
+    {context, html}
+  end
+
+  defp render_block(%Block.HtmlComment{lines: lines}, context) do
+    {context, lines}
+  end
+
+  defp render_block(%Block.HtmlOneline{html: html}, context) do
+    {context, html}
+  end
+
+  #########
+  # Ruler #
+  #########
+  defp render_block(%Block.Ruler{lnb: lnb, attrs: attrs}, context) do
+    add_attrs(context, "<hr />", attrs, [], lnb)
+  end
+
+  ###########
+  # Heading #
+  ###########
+  defp render_block(
+         %Block.Heading{lnb: lnb, level: level, content: content, attrs: attrs},
+         context
+       ) do
+    converted = convert(content, lnb, context)
+    html = "<h#{level}>#{converted.value}</h#{level}>"
+    add_attrs(converted, html, attrs, [], lnb)
+  end
+
+  ##############
+  # Blockquote #
+  ##############
+
+  defp render_block(%Block.BlockQuote{lnb: lnb, blocks: blocks, attrs: attrs}, context) do
+    {context1, body} = render(blocks, context)
+    html = "<blockquote>#{body}</blockquote>"
+    add_attrs(context1, html, attrs, [], lnb)
+  end
+
+  #########
+  # Table #
+  #########
+
+  defp render_block(
+         %Block.Table{lnb: lnb, header: header, rows: rows, alignments: aligns, attrs: attrs},
+         context
+       ) do
+    {context1, html} = add_attrs(context, "<table>", attrs, [], lnb)
+    context2 = set_value(context1, html)
+
+    context3 =
+      if header do
+        append(add_trs(append(context2, "<thead>"), [header], "th", aligns, lnb), "</thead>")
+      else
+        # Maybe an error, needed append(context, html)
+        context2
+      end
+
+    context4 = append(add_trs(append(context3, "<tbody>"), rows, "td", aligns, lnb), "</tbody>")
+
+    {context4, [context4.value, "</table>"]}
+  end
+
+  ########
+  # Code #
+  ########
+
+  defp render_block(
+         %Block.Code{lnb: lnb, language: language, attrs: attrs} = block,
+         %Context{options: options} = context
+       ) do
+    class =
+      if language, do: ~s{ class="#{code_classes(language, options.code_class_prefix)}"}, else: ""
+
+    tag = ~s[<pre><code#{class}>]
+    lines = options.render_code.(block)
+    html = ~s[#{tag}#{lines}</code></pre>]
+    add_attrs(context, html, attrs, [], lnb)
+  end
+
+  #########
+  # Lists #
+  #########
+
+  defp render_block(
+         %Block.List{lnb: lnb, type: type, blocks: items, attrs: attrs, start: start},
+         context
+       ) do
+    {context1, content} = render(items, context)
+    html = "<#{type}#{start}>#{content}</#{type}>"
+    add_attrs(context1, html, attrs, [], lnb)
+  end
+
+  # format a single paragraph list item, and remove the para tags
+  defp render_block(
+         %Block.ListItem{lnb: lnb, blocks: blocks, spaced: false, attrs: attrs},
+         context
+       )
+       when length(blocks) == 1 do
+    {context1, content} = render(blocks, context)
+    content = Regex.replace(~r{</?p>}, content, "")
+    html = "<li>#{content}</li>"
+    add_attrs(context1, html, attrs, [], lnb)
+  end
+
+  # format a spaced list item
+  defp render_block(%Block.ListItem{lnb: lnb, blocks: blocks, attrs: attrs}, context) do
+    {context1, content} = render(blocks, context)
+    html = "<li>#{content}</li>"
+    add_attrs(context1, html, attrs, [], lnb)
+  end
+
+  ##################
+  # Footnote Block #
+  ##################
+
+  defp render_block(%Block.FnList{blocks: footnotes}, context) do
+    items =
+      Enum.map(footnotes, fn note ->
+        blocks = append_footnote_link(note)
+        %Block.ListItem{attrs: "#fn:#{note.number}", type: :ol, blocks: blocks}
+      end)
+
+    {context1, html} = render_block(%Block.List{type: :ol, blocks: items}, context)
+    {context1, Enum.join([~s[<div class="footnotes">], "<hr />", html, "</div>"])}
+  end
+
+  #######################################
+  # Isolated IALs are rendered as paras #
+  #######################################
+
+  defp render_block(%Block.Ial{verbatim: verbatim}, context) do
+    {context, "<p>{:#{verbatim}}</p>"}
+  end
+
+  ####################
+  # IDDef is ignored #
+  ####################
+
+  defp render_block(%Block.IdDef{}, context), do: {context, ""}
+
+  #####################################
+  # And here are the inline renderers #
+  #####################################
+
+  defdelegate br, to: HtmlRenderer
+  defdelegate codespan(text), to: HtmlRenderer
+  defdelegate em(text), to: HtmlRenderer
+  defdelegate strong(text), to: HtmlRenderer
+  defdelegate strikethrough(text), to: HtmlRenderer
+
+  defdelegate link(url, text), to: HtmlRenderer
+  defdelegate link(url, text, title), to: HtmlRenderer
+
+  defdelegate image(path, alt, title), to: HtmlRenderer
+
+  defdelegate footnote_link(ref, backref, number), to: HtmlRenderer
+
+  # Table rows
+  defp add_trs(context, rows, tag, aligns, lnb) do
+    numbered_rows =
+      rows
+      |> Enum.zip(Stream.iterate(lnb, &(&1 + 1)))
+
+    numbered_rows
+    |> Enum.reduce(context, fn {row, lnb}, ctx ->
+      append(add_tds(append(ctx, "<tr>"), row, tag, aligns, lnb), "</tr>")
+    end)
+  end
+
+  defp add_tds(context, row, tag, aligns, lnb) do
+    Enum.reduce(1..length(row), context, add_td_fn(row, tag, aligns, lnb))
+  end
+
+  defp add_td_fn(row, tag, aligns, lnb) do
+    fn n, ctx ->
+      style =
+        case Enum.at(aligns, n - 1, :default) do
+          :default -> ""
+          align -> " style=\"text-align: #{align}\""
+        end
+
+      col = Enum.at(row, n - 1)
+      converted = convert(col, lnb, set_messages(ctx, []))
+      append(add_messages_from(ctx, converted), "<#{tag}#{style}>#{converted.value}</#{tag}>")
+    end
+  end
+
+  ###############################
+  # Append Footnote Return Link #
+  ###############################
+
+  defdelegate append_footnote_link(note), to: HtmlRenderer
+  defdelegate append_footnote_link(note, fnlink), to: HtmlRenderer
+
+  defdelegate render_code(lines), to: HtmlRenderer
+
+  defp code_classes(language, prefix) do
+    ["" | String.split(prefix || "")]
+    |> Enum.map(fn pfx -> "#{pfx}#{language}" end)
+    |> Enum.join(" ")
+  end
+end
diff --git a/lib/pleroma/web/common_api/utils.ex b/lib/pleroma/web/common_api/utils.ex
index 348fdedf1..635e7cd38 100644
--- a/lib/pleroma/web/common_api/utils.ex
+++ b/lib/pleroma/web/common_api/utils.ex
@@ -331,7 +331,7 @@ defmodule Pleroma.Web.CommonAPI.Utils do
   def format_input(text, "text/markdown", options) do
     text
     |> Formatter.mentions_escape(options)
-    |> Earmark.as_html!()
+    |> Earmark.as_html!(%Earmark.Options{renderer: Pleroma.EarmarkRenderer})
     |> Formatter.linkify(options)
     |> Formatter.html_escape("text/html")
   end