app.rb

require './env'
require 'bundler/setup'
require 'json'
require 'sinatra'
require 'sinatra/json'
require 'sinatra/activerecord'

Dir[File.dirname(__FILE__) + '/models/*.rb'].each {|file| require file }

class SlidesApplication < Sinatra::Application

  register Sinatra::ActiveRecordExtension
  enable :sessions

  configure :development, :test do
    require 'pry'
  end

  #Serve the index document
  get '/' do
    File.read(File.join('public', 'index.html'))
  end

  get '/api/courses' do
    json Course.all
  end

  get '/api/courses/:course' do

    begin
      json Course.find(params[:course])
    rescue ActiveRecord::RecordNotFound
      halt 404
    end

  end

  get '/api/courses/:course/presentations' do

    begin
      json Course.find( params[:course] ).presentations.order( :position )
    rescue ActiveRecord::RecordNotFound
      halt 404
    end

  end

  post '/api/courses/:course/presentations' do
    body         = JSON.parse request.body.read
    presentation = Presentation.new
    presentation_save( params[:course] , presentation , body )
  end

  get '/api/courses/:course/presentations/:presentation' do

    begin
      content_type :json
      Presentation.find( params[:presentation] ).to_json :methods => :content
    rescue ActiveRecord::RecordNotFound
      halt 404
    end

  end

  put '/api/courses/:course/presentations/:presentation' do
    body         = JSON.parse request.body.read
    presentation = Presentation.find( params[:presentation] )
    presentation_save( presentation.course_id , presentation , body )
  end

  delete '/api/courses/:course/presentations/:presentation' do
    presentation = Presentation.find( params[:presentation] )
    presentation.delete
  end

  def presentation_save( course_id , presentation , body )

    ActiveRecord::Base.transaction do

      #Save presentation
      presentation.course_id = course_id
      presentation.name      = body['name']
      presentation.position  = 0 # TODO Set the position as the last item
      presentation.save!

      # Find the slides not available in the body
      toDelete = Array.new(presentation.slides).reject! { | slide |
        body['slides'].index { | slideBody | slideBody["id"] == slide.id }
      }
      toDelete.each { | slide | slide.destroy } if toDelete != nil

      #Update or craete new slides
      i = 0
      presentation.slides = body['slides'].map do | slideBody  |
          if( slideBody['id'] )
            slide = Slide.find( slideBody['id'] )
          else
            slide = Slide.new
          end

          puts i

          slide.content      = slideBody['content']
          slide.valign       = slideBody['valign'] || 'top'
          slide.halign       = slideBody['halign'] || 'left'
          slide.position     = i
          slide.presentation_id = presentation.id
          slide.save!
          i += 1
          slide
      end

    end

    ""

  end

  get '/api/courses/:course/presentations/:presentation/slides' do

    begin
      json Presentation.find( params[:presentation] ).slides.sort_by(&:position)
    rescue ActiveRecord::RecordNotFound
      halt 404
    end

  end

  not_found do
    "Not Found"
  end

  run! if __FILE__ == $0

end