Camofy html image sources (#467)

* write a regex for html images. might not be perfect

* linter was annoying

* I'm not used to how ruby deals with returns

* running the linter is a pain

* rename variable

* improve regex to be more acommodating to general whitespace

app/helpers/markdown_helper.rb

@@ -1,16 +1,44 @@
 module MarkdownHelper
   include CamoHelper
 
-  def camofy(markdown)
-    return unless markdown
+  def camofy(text)
+    return unless text
 
-    markdown.gsub(markdown_img_regex) do
+    text = sub_markdown(text)
+    sub_html(text)
+  end
+
+  def sub_markdown(text)
+    text.gsub(markdown_img_regex) do
       "![#{Regexp.last_match(1)}](#{camo(Regexp.last_match(2))}#{Regexp.last_match(3)})"
     end
   end
 
+  def sub_html(text)
+    text.gsub(html_img_regex) do
+      preceding_src = Regexp.last_match(1)
+      quote_mark = Regexp.last_match(2)
+      url = Regexp.last_match(3)
+      ending = Regexp.last_match(4)
+      "<img#{preceding_src}src=#{quote_mark}#{camo(url)}#{quote_mark}#{ending}"
+    end
+  end
+
   def markdown_img_regex
     # ![alt text](url =widthxheight "title")
     /!\[([^\[]*)\]\(([^\ )]+)(( =[^)]?[^ ]+)?( [^)]?"[^)]+")?)?\)/
   end
+
+  def html_img_regex
+    # warning: this regex may not be perfect. They rarely are.
+    # If you find an edge case, improve this regex!
+    # <img...something... src="url"...ending...
+    # or, the alternative quotes: <img...something... src='url'...ending...
+    # or, even without quotes: <img...something... src=url...ending...
+    # and the ...ending... can be either a space, a > or />
+    # note that we don't allow mismatched quotes like 'url" or shenanigans like that
+    # This regex contains two particularly useful features:
+    #  capturing groups, and lazy matching.
+    %r{<img([^>]*\s)src=(["']?)(.+?)\2(\s|>|/)}
+  end
 end

spec/helpers/markdown_helper_spec.rb

@@ -29,6 +29,43 @@
         '![](https://example.org/c7125941763fc18c9d8977ed19028ca5f9378070/687474703a2f2f6578616d706c652e6f72672f696d6167652e6a7067 =100x* "Image title")'
       )
     end
+
+    it do
+      expect(camofy('<img src="http://example.org/image.jpg">')).to eq(
+        '<img src="https://example.org/c7125941763fc18c9d8977ed19028ca5f9378070/687474703a2f2f6578616d706c652e6f72672f696d6167652e6a7067">'
+      )
+    end
+
+    it do
+      expect(camofy("<img src='http://example.org/image.jpg'>")).to eq(
+        "<img src='https://example.org/c7125941763fc18c9d8977ed19028ca5f9378070/687474703a2f2f6578616d706c652e6f72672f696d6167652e6a7067'>"
+      )
+    end
+
+    it do
+      expect(camofy('<img src="http://example.org/image.jpg"/>')).to eq(
+        '<img src="https://example.org/c7125941763fc18c9d8977ed19028ca5f9378070/687474703a2f2f6578616d706c652e6f72672f696d6167652e6a7067"/>'
+      )
+    end
+
+    it do
+      expect(camofy('<img src="http://example.org/image.jpg" />')).to eq(
+        '<img src="https://example.org/c7125941763fc18c9d8977ed19028ca5f9378070/687474703a2f2f6578616d706c652e6f72672f696d6167652e6a7067" />'
+      )
+    end
+
+    it do
+      expect(camofy('<img src="http://example.org/image.jpg" style="somekindofstyle" >')).to eq(
+        '<img src="https://example.org/c7125941763fc18c9d8977ed19028ca5f9378070/687474703a2f2f6578616d706c652e6f72672f696d6167652e6a7067" style="somekindofstyle" >'
+      )
+    end
+
+    it do
+      expect(camofy('<img alt="" style="somekindofstyle" src="http://example.org/image.jpg">')).to eq(
+        '<img alt="" style="somekindofstyle" src="https://example.org/c7125941763fc18c9d8977ed19028ca5f9378070/687474703a2f2f6578616d706c652e6f72672f696d6167652e6a7067">'
+      )
+    end
+
     # rubocop:enable Layout/LineLength
   end
 end