Prepare for the switch from strings to arrays for tags and receipts.

Old behavior: Send tags and receipts as a comma separated string.
New behavior: Send them as array of strings.

src/cgi.cpp

@@ -77,10 +77,24 @@ entry_type parse_formdata()
     }
 
     entry.instance = cgi("instance");
+    if (!cgi("tags").empty()) // Old form.
+    {
         entry.tags = string_to_vector(cgi("tags"));
+    }
+    else
+    {
+        entry.tags = get_array("tags[]");
+    }
     transform(entry.tags.begin(), entry.tags.end(), entry.tags.begin(),
               [](const auto &tag) { return tolower(tag); });
+    if (!cgi("receipts").empty()) // Old form.
+    {
         entry.receipts = string_to_vector(cgi("receipts"));
+    }
+    else
+    {
+        entry.receipts = get_array("receipts[]");
+    }
     entry.description = cgi("description");
     entry.report_time = time::to_string(system_clock::now());
 
@@ -143,26 +157,26 @@ vector<string> string_to_vector(const string_view str)
     return vec;
 }
 
-vector<string> get_tags()
+vector<string> get_array(const string &name)
 {
     cgicc::Cgicc cgi;
-    vector<cgicc::FormEntry> tags_form;
+    vector<cgicc::FormEntry> form;
-    vector<string> tags_string;
+    vector<string> values;
 
-    cgi.getElement("tags[]", tags_form);
+    cgi.getElement(name, form);
-    for (const auto &element : tags_form)
+    for (const auto &element : form)
     {
-        const string tag{element.getValue()};
+        const string value{element.getValue()};
-        if (!tag.empty())
+        if (!value.empty())
         {
-            const auto new_tags{string_to_vector(tolower(tag))};
+            const auto new_values{string_to_vector(tolower(value))};
-            tags_string.insert(tags_string.end(),
+            values.insert(values.end(),
-                               std::make_move_iterator(new_tags.begin()),
+                          std::make_move_iterator(new_values.begin()),
-                               std::make_move_iterator(new_tags.end()));
+                          std::make_move_iterator(new_values.end()));
         }
     }
 
-    return tags_string;
+    return values;
 }
 
 string tolower(const string_view str)

src/cgi.hpp

@@ -39,13 +39,11 @@ using std::vector;
 [[nodiscard]] vector<string> string_to_vector(string_view str);
 
 /*!
- *  @brief  Read tags from QUERY_STRING or stdin and return it as a vector.
+ *  @brief  Read array from QUERY_STRING or stdin and return it as a vector.
- *
- *          For use in rss.cpp.
  *
  *  @since  0.1.0
  */
-[[nodiscard]] vector<string> get_tags();
+[[nodiscard]] vector<string> get_array(const string &name);
 
 // Return str in lowercase.
 [[nodiscard]] string tolower(string_view str);

src/generators/rss.cpp

@@ -222,7 +222,7 @@ int main(int /*argc*/, char * /*argv*/[])
             // Ignore, use old version of repo.
         }
         const auto entries{files::read_json_files(true)};
-        write_rss(cout, entries, cgi::get_tags());
+        write_rss(cout, entries, cgi::get_array("tags[]"));
     }
     catch (const exception &e)
     {