Add AttachmentToHTML library

Extracts the attachment processing from FoiAttachment#body_to_html

AttachmentToHTML contains adapters which convert
  - text/plain
  - application/pdf
  - application/rtf

Results are returned as an AttachmentHTML::HTML instance which contains
the raw HTML and other metadata about the conversion.

1 files changed, 41 insertions, 0 deletions

diff --git a/lib/attachment_to_html/attachment_to_html.rb b/lib/attachment_to_html/attachment_to_html.rb
new file mode 100644
index 000000000..5f63661b4
--- /dev/null
+++ b/lib/attachment_to_html/attachment_to_html.rb
@@ -0,0 +1,41 @@
+require 'html'
+
+Dir[File.dirname(__FILE__) + '/adapters/*.rb'].each do |file|
+    require file
+end
+
+module AttachmentToHTML
+    extend self
+
+    def to_html(attachment, opts = {})
+        adapter = adapter_for(attachment).new(attachment, opts)
+        html = HTML.new(adapter)
+
+        if html.success?
+            html
+        else
+            fallback = fallback_adapter_for(attachment).new(attachment, opts)
+            HTML.new(fallback)
+        end
+    end
+
+    private
+
+    def adapter_for(attachment)
+        case attachment.content_type
+        when 'text/plain' then Adapters::Text
+        when 'application/pdf' then Adapters::PDF
+        when 'application/rtf' then Adapters::RTF
+        else
+            fallback_adapter_for(attachment)
+        end
+    end
+
+    def fallback_adapter_for(attachment)
+        if attachment.has_google_docs_viewer?
+            Adapters::GoogleDocsViewer
+        else
+            Adapters::CouldNotConvert
+        end
+    end
+end