custom validation gives blank field after validation which is not right - ruby-on-rails

Question

I have a custom validation in my model like this:
class Appointment < ActiveRecord::Base
#VIRTUAL ATTRIBUTES
attr_accessor :start_date, :start_time, :duration
#RELATIONSHIPS
belongs_to :task
#VALIDATIONS
before_validation :convert_to_datetime
before_validation :dur
validates :duration, presence: true
validate :is_date_nil
validate :time_collision_validation, if: :is_appointments_not_empty
validate :check_time
after_save :save_start_date
def is_appointments_not_empty
Appointment.all.present?
end
def check_time
start_at = Time.parse("#{#start_date} #{#start_time}")
if start_at < Time.now
errors.add(:start_date, "Cannot input past times")
end
end
def convert_to_datetime
unless #start_date.blank? && #start_time.blank?
self.start_at = Time.parse("#{#start_date} #{#start_time}")
end
end
def dur
if #start_date.present? && #start_time.present? && #duration.present?
self.end_at = Time.parse("#{#start_date} #{#start_time}") + (#duration.to_f*60*60)
end
end
def time_collision_validation
appointments = Appointment.all
if #start_date.present? && #start_time.present? && duration == 0.to_s
start_at = Time.parse("#{#start_date} #{#start_time}")
end_at = Time.parse("#{#start_date} #{#start_time}") + (#duration.to_f*60*60)
appointments.each do |a|
if start_at <= a.end_at - (2*60*60) && start_at >= a.start_at - (1*60*60)
errors.add(:start_time)
errors.add(:start_date, "An appointment already
exists at #{a.start_at.strftime("%I:%M%p")} of #{a.start_at.strftime("%d/%m/%Y")}
to #{a.end_at.strftime("%I:%M%p")} of #{a.end_at.strftime("%d/%m/%Y")}.
Please select a different date or time.")
break
end
end
elsif #start_date.present? && #start_time.present? && duration.present?
start_at = Time.parse("#{#start_date} #{#start_time}")
end_at = Time.parse("#{#start_date} #{#start_time}") + (#duration.to_f*60*60)
appointments.each do |a|
if start_at <= a.end_at - (2*60*60) && a.start_at <= end_at
errors.add(:start_time)
errors.add(:start_date, "An appointment already
exists at #{a.start_at.strftime("%I:%M%p")} of #{a.start_at.strftime("%d/%m/%Y")}
to #{a.end_at.strftime("%I:%M%p")} of #{a.end_at.strftime("%d/%m/%Y")}.
Please select a different date or time.")
break
end
end
end
end
def is_date_nil
if #start_date.blank? && #start_time.blank?
errors.add(:start_date, "Start date can't be blank")
errors.add(:start_time, "Start time can't be blank")
end
if #start_date.blank? && #start_time.present?
errors.add(:start_date, "Start date can't be blank")
end
if #start_time.blank? && #start_date.present?
errors.add(:start_time, "Start time can't be blank")
end
end
def start_date=(date)
#start_date = Date.strptime(date, "%d/%m/%Y") if date.present?
end
# def save_start_date
# #start_date = Date.strptime(#start_date, "%d/%m/%Y") if #start_date.present?
# end
# def save_start_date
# #start_date = Date.parse(#start_date).strftime("%d/%m/%Y")if #start_date.present?
# end
def start_time=(time)
#start_time = Time.parse(time).strftime("%H:%M:%S") if time.present?
end
def duration=(duration)
#duration = duration if duration.present?
end
# def start_date
# #start_date.strftime("%d/%m/%Y") if start_at.present? # || start_at.strftime("%d/%m/%Y") if start_at.present?
# end
def start_date
unless #start_date.blank?
#start_date.strftime("%d/%m/%Y")
end
# start_at.strftime("%d/%m/%Y") if start_at.present?
end
def start_time
#start_time || start_at.strftime("%I:%M%p") if start_at.present?
end
# def duration
# #duration || 9
# end
end
After this time_collision_validation executes, the value fields are blank which I don't want because I'm concerned with UX. ie: start_date and start_time fields are blank.
When I checked the value attribute in input in the HTML source code, the value contains a date string. I wonder why it does not show in the field.
Can somebody help me with this and explain what is going on please? >.<

Answer 1

validate :time_collision_validation
def time_collision_validation
appointments = Appointment.all
if self.start_date.present? && self.start_time.present? && duration.present?
start_at = Time.parse("#{self.start_date} #{self.start_time}")
end_at = Time.parse("#{self.start_date} #{self.start_time}") + (self.duration.to_f.hours)
appointments.each do |appointment|
if duration == 0.to_s
duration_ok = start_at >= appointment.start_at - (1.hours)
else
duration_ok = appointment.start_at <= end_at
end
if start_at <= appointment.end_at - (2.hours) && duration_ok
errors.add(:start_time)
errors.add(:start_date, "An appointment already
exists at #{appointment.start_at.strftime("%I:%M%p")} of #{appointment.start_at.strftime("%d/%m/%Y")}
to #{appointment.end_at.strftime("%I:%M%p")} of #{appointment.end_at.strftime("%d/%m/%Y")}.
Please select a different date or time.")
break
end
end
end
end
Notes:
you variously refer to duration and self.duration. For readability i would always use self.duration rather than duration or self.duration as it makes it clear to the reader that you are talking about a method/field of the current object rather than a local variable. I've change all instances of referencing methods/fields of the current object to self.methodname
you had a lot of repetition shared between the two if cases. I've refactored these to avoid repetition.
2*60*60 is like saying 2.hours and the latter is much more readable.
what are start_date and start_time - are they strings or date/time objects?
rather than loading every appointment in your entire database, and cycling through them, it would be much more efficient to just search for a single colliding other appointment. if you find one then you can add the errors. I was tempted to do this here but it's not clear exactly what's going on with your database.