1 files changed, 42 insertions, 0 deletions
diff --git a/src/guff/tag-model.cr b/src/guff/tag-model.cr
index 5d758d1..2aa9d89 100644
--- a/src/guff/tag-model.cr
+++ b/src/guff/tag-model.cr
@@ -1,10 +1,52 @@
 module Guff
   class TagModel < Model
     SQL = TemplateCache.new({
+      add_tags: "
+        INSERT INTO tags(name) VALUES(%{tags})
+      ",
+
+      get_tags: "
+        SELECT tag_id,
+               name
+
+          FROM tags
+
+         WHERE name IN (%{tags})
+      ",
     } of Symbol => String)
 
     def initialize(models : Models)
       super(models, SQL)
     end
+
+    def add_tags(tags : Array(String))
+      # get ids of existing tags
+      ids = get_ids(tags)
+
+      query(:add_tags, nil, {
+        "tags": tags.reject { |tag|
+          ids[tag]?
+        }.map { |tag|
+          "'" + @db.quote(tag) + "'"
+        }.join(','),
+      })
+    end
+
+    private def get_ids(
+      tags = [] of String : Array(String)
+    ) : Hash(String, Int32)
+      r = {} of String => Int32
+
+      all(:get_tags, nil, {
+        "tags": tags.map { |tag|
+          "'" + @db.quote(tag) + "'"
+        }.join(','),
+      }) do |row|
+        r[row["name"] as String] = (row["tag_id"] as String).to_i
+      end
+
+      # return result
+      r
+    end
   end
 end