Notes for Jacob

form.erb

<form method="post" action="/movies/index">
  <label>Runtime</label>
  <select name="runtime">
    <option value="0">Under 90 minutes</option>
    <option value="1">Between 90 and 120 minutes</option>
    <option value="2">Over 120 minutes</option>
  </select>

  <label>Title</label>
  <input type="text" name="title">

  <label>Director</label>
  <input type="text" name="director">

  <input type="submit" value="Submit">
</form>

rails_code.rb

class MoviesController < ApplicationController
  def index
    queries = []
    queries << [:title, params[:title]] if params[:title]
    queries << [:director, params[:director]] if params[:director]
    queries << [:runtime, params[:runtime]] if params[:runtime]
    # [[:title, "Mad Max"], [:runtime, "0"]]
    if queries.empty?
      @movies = Movies.all
    else
      @movies = Movies.search(queries)
    end
  end
end

class Movie < ActiveRecord::Base
  RUNTIME_QUERIES = ["runtime_in_minutes <= 90"
                     "runtime_in_minutes > 90 and runtime_in_minutes <= 120"
                     "runtime_in_minutes > 120"]

  class << self
    def query_for(query)
      search_type, term = query
      case type
      when :title
        ["title LIKE ?", "%#{term}%"]
      when :director
        ["director LIKE ?", "%#{term}%"]
      when :runtime
        RUNTIME_QUERIES[term.to_i]
      end
    end

    def search(queries)
      results = Movie.none
      queries.each do |tuple|
        results = results.where(query_for(tuple))
      end
      results
    end
  end
end