uploads: add new source:<url> dupe check (fix #3873)

* On the /uploads/new page, instead of just showing a "This post has
probably already been uploaded" message, show the actual thumbnails of
posts having the same source as what the user is trying to upload.

* Move the iqdb results section up top, beside the related posts section.

app/controllers/uploads_controller.rb

@@ -4,6 +4,7 @@ class UploadsController < ApplicationController
   skip_before_action :verify_authenticity_token, only: [:preprocess]
 
   def new
+    @source = Sources::Strategies.find(params[:url], params[:ref]) if params[:url].present?
     @upload_notice_wiki = WikiPage.titled(Danbooru.config.upload_notice_wiki_page).first
     @upload, @remote_size = UploadService::ControllerHelper.prepare(
       url: params[:url], ref: params[:ref]
@@ -13,7 +14,7 @@ class UploadsController < ApplicationController
 
   def batch
     @url = params.dig(:batch, :url) || params[:url]
-    @source = UploadService::ControllerHelper.batch(@url, params[:ref])
+    @source = Sources::Strategies.find(@url, params[:ref]) if @url.present?
     respond_with(@source)
   end
 

app/javascript/src/styles/specific/uploads.scss

@@ -9,10 +9,19 @@ div#c-uploads {
       margin-bottom: 2em;
     }
 
-    ul#links {
+    ul#upload-image-metadata, ul#links {
       margin-bottom: 1em;
     }
 
+    div#related-posts-by-source, div#iqdb-similar {
+      display: inline-block;
+
+      .hint {
+        white-space: nowrap;
+        max-width: 100%;
+      }
+    }
+
     label[for="upload_as_pending"] {
       display: inline;
     }

app/logical/sources/strategies/base.rb

@@ -179,6 +179,18 @@ module Sources
         return {}
       end
 
+      # A search query that should return any posts that were previously
+      # uploaded from the same source. These may be duplicates, or they may be
+      # other posts from the same gallery.
+      def related_posts_search_query
+        "source:#{canonical_url}"
+      end
+
+      def related_posts(limit = 5)
+        CurrentUser.as_system { Post.tag_match(related_posts_search_query).paginate(1, limit: limit) }
+      end
+      memoize :related_posts
+
       def to_h
         return {
           :artist_name => artist_name,

app/logical/sources/strategies/pixiv.rb

@@ -153,6 +153,10 @@ module Sources
         translated_tags
       end
 
+      def related_posts_search_query
+        illust_id.present? ? "pixiv:#{illust_id}" : "source:#{canonical_url}"
+      end
+
     public
 
       def image_urls_sub

app/logical/upload_service/controller_helper.rb

@@ -23,11 +23,5 @@ class UploadService
 
       return [upload]
     end
-
-    def self.batch(url, ref = nil)
-      if url
-        return Sources::Strategies.find(url, ref)
-      end
-    end
   end
 end

app/views/iqdb_queries/_matches.html.erb

@@ -1,9 +1,11 @@
 <% if @matches.present? %>
-  <h3>Similar</h3>
+  <h3>Similar Posts</h3>
+  <p class="hint">Found <%= pluralize(@matches.length, "similar post") %>:</p>
+
   <% @matches.each do |match| %>
     <%= PostPresenter.preview(match["post"], :tags => "status:any", :similarity => match["score"], :size => true) %>
   <% end %>
 <% else %>
-  <h3>Similar</h3>
+  <h3>Similar Posts</h3>
-  <p>No matches found</p>
+  <p class="hint">No similar posts found.</p>
 <% end %>

app/views/uploads/_image.html.erb

@@ -5,7 +5,7 @@
     <%= image_tag(@source.image_url, :title => "Preview", :id => "image") %>
   <% end %>
 
-  <ul>
+  <ul id="upload-image-metadata">
     <% if @remote_size %>
       <li><strong>Size:</strong> <%= number_to_human_size(@remote_size) %></li>
     <% end %>

app/views/uploads/_related_posts.html.erb

@@ -0,0 +1,27 @@
+<%# source %>
+
+<% if source.present? && source.related_posts.present? %>
+  <div id="related-posts-by-source">
+    <h3>Related Posts</h3>
+
+    <p class="hint">
+      Found <%= link_to pluralize(source.related_posts.total_count, "other post"), posts_path(tags: source.related_posts_search_query) %> from the same source:
+    </p>
+
+    <div>
+      <% source.related_posts.each do |post| %>
+        <%= PostPresenter.preview(post, show_deleted: true, size: true) %>
+      <% end %>
+    </div>
+  </div>
+<% end %>
+
+<% if Danbooru.config.iqdbs_server %>
+  <% if params[:url] %>
+    <div class="input" id="iqdb-similar">
+      <p><em>Loading similar...</em></p>
+    </div>
+  <% else %>
+    <div class="input" id="iqdb-similar" style="display: none;"></div>
+  <% end %>
+<% end %>

app/views/uploads/new.html.erb

@@ -12,6 +12,7 @@
       <% end %>
 
       <%= render "image" %>
+      <%= render "related_posts", source: @source %>
       <%= render "sources/info" %>
 
       <div id="client-errors" class="error-messages ui-state-error ui-corner-all" style="display:none"></div>
@@ -90,16 +91,6 @@
           </div>
         </div>
 
-        <% if Danbooru.config.iqdbs_server %>
-          <% if params[:url] %>
-            <div class="input" id="iqdb-similar">
-              <p><em>Loading similar...</em></p>
-            </div>
-          <% else %>
-            <div class="input" id="iqdb-similar" style="display: none;"></div>
-          <% end %>
-        <% end %>
-
         <div class="input">
           <div>
             <%= f.label :tag_string, "Tags" %>