Enabled instructor search through some spicy joins

schedules/app/models/course.rb

@@ -52,6 +52,8 @@ class Course < ApplicationRecord
         query = from_course_number(query, value)
       when "title"
         query = from_title(query, value)
+      when "instructor"
+        query = Instructor.from_name(query.joins("INNER JOIN instructors ON course_sections.instructor_id = instructors.id"), value)
       end
     end
 

schedules/app/models/course_section.rb

@@ -57,7 +57,7 @@ class CourseSection < ApplicationRecord
     /\d+/.match(query) { |a|
       m = a.to_s
       if m.length == query.length # Does the number take up the entire query
-        if m.length == 5 # Check if it is a CRN
+        if m.length == 5 and from_crn(select("*"), m).count != 0 # Check if it is a CRN
           filters["crn"] = m
         else # Just assume course_id
           filters["course_id"] = Integer(m)

schedules/app/models/instructor.rb

 class Instructor < ApplicationRecord
   has_many :course_sections
 
-  def self.named(base_query, name)
-    base_query.where("name LIKE ?", "%#{name}%")
+  def self.from_name(base_query, name)
+    base_query.where("instructors.name LIKE ?", "%#{name}%")
   end
 end