require 'set'
require 'harvested'

module TomatoHarvest
  class TimeEntry

    attr_accessor :options

    def self.build_and_test(options = {})
      required = ["domain", "username", "password", "project", "task", "name"].to_set
      keys = options.keys.to_set
      if required.subset?(keys)
        new(options).tap do |entry|
          entry.test
        end
      end
    end

    def initialize(options = {})
      self.options = options
    end

    ##
    # Check that the project and task were found on Harvest

    def test
      raise "Couldn't find project"   unless project
      raise "Couldn't find task type" unless task
    end

    ##
    # Persist time entry to Harvest tracker

    def log(seconds)
      hours = seconds_to_hours(seconds)
      options = {
        notes: notes,
        hours: hours,
        spent_at: date,
        project_id: project.id,
        task_id: task.id
      }


      existing_entry = time_api.all.find do |entry|
        entry.notes == self.notes
      end

      if existing_entry
        existing_entry.hours += hours
        existing_entry.spent_at = date
        time_api.update(existing_entry)
      else
        entry = Harvest::TimeEntry.new(options)
        time_api.create(entry)
      end
    end

    ##
    # Notes to send to tracker

    def notes
      options["name"]
    end

    ##
    # Date for task (today), formatted properly for tracker

    def date
      Date.today
    end

    ##
    # Convert seconds into hours

    def seconds_to_hours(seconds)
      minutes = (seconds / 60.0)
      unrounded = (minutes / 60.0)
      (unrounded * 100).ceil / 100.0
    end

    ##
    # Harvest project with name matching options[:project]

    def project
      time_api.trackable_projects.find do |project|
        project.name == options["project"]
      end
    end

    ##
    # Harvest task with name matching options[:task]

    def task
      project.tasks.find do |task|
        task.name == options["task"]
      end
    end

    private

    def time_api
      @time_api ||= begin
        client = Harvest.client(options["domain"], options["username"], options["password"])
        Harvest::API::Time.new(client.credentials)
      end
    end

  end
end