module Chouette
  class TimeTable < Chouette::TridentActiveRecord
    has_metadata
    include ChecksumSupport
    include TimeTableRestrictions
    include ObjectidSupport
    include ApplicationDaysSupport
    include TimetableSupport

    acts_as_taggable

    attr_accessor :tag_search

    def self.ransackable_attributes auth_object = nil
      (column_names + ['tag_search']) + _ransackers.keys
    end

    ransacker :unaccented_comment, formatter: ->(val){ val.parameterize } do
      Arel.sql('unaccent(time_tables.comment)')
    end

    has_and_belongs_to_many :vehicle_journeys, :class_name => 'Chouette::VehicleJourney'

    has_many :dates, -> {order(:date)}, inverse_of: :time_table, :validate => :true, :class_name => "Chouette::TimeTableDate", :dependent => :destroy
    has_many :periods, -> {order(:period_start)}, inverse_of: :time_table, :validate => :true, :class_name => "Chouette::TimeTablePeriod", :dependent => :destroy

    belongs_to :calendar
    belongs_to :created_from, class_name: 'Chouette::TimeTable'

    scope :overlapping, -> (period_range) do
      joins("
        LEFT JOIN time_table_periods ON time_tables.id = time_table_periods.time_table_id
        LEFT JOIN time_table_dates ON time_tables.id = time_table_dates.time_table_id
      ")
      .where("(time_table_periods.period_start <= :end AND time_table_periods.period_end >= :begin) OR (time_table_dates.date BETWEEN :begin AND :end)", {begin: period_range.begin, end: period_range.end})
    end

    after_save :save_shortcuts

    def local_id
      "IBOO-#{self.referential.id}-#{self.id}"
    end

    def checksum_attributes
      [].tap do |attrs|
        attrs << self.int_day_types
        dates = self.dates
        dates += TimeTableDate.where(time_table_id: self.id)
        attrs << dates.map(&:checksum).map(&:to_s).uniq.sort
        periods = self.periods
        periods += TimeTablePeriod.where(time_table_id: self.id)
        attrs << periods.map(&:checksum).map(&:to_s).uniq.sort
      end
    end

    has_checksum_children TimeTableDate
    has_checksum_children TimeTablePeriod

    def self.object_id_key
      "Timetable"
    end

    accepts_nested_attributes_for :dates, :allow_destroy => :true
    accepts_nested_attributes_for :periods, :allow_destroy => :true

    validates_presence_of :comment
    validates_associated :dates
    validates_associated :periods

    def continuous_dates
      in_days = self.dates.where(in_out: true).sort_by(&:date)
      chunk = {}
      group = nil
      in_days.each_with_index do |date, index|
        group ||= index
        group = (date.date == in_days[index - 1].date + 1.day) ? group : group + 1
        chunk[group] ||= []
        chunk[group] << date
      end
      # Remove less than 2 continuous day chunk
      chunk.values.delete_if {|dates| dates.count < 2}
    end

    def color
      _color = read_attribute(:color)
      _color.present? ? _color : nil
    end

    def convert_continuous_dates_to_periods
      chunks = self.continuous_dates

      transaction do
        chunks.each do |chunk|
          self.periods.create!(period_start: chunk.first.date, period_end: chunk.last.date)
          self.dates.delete(chunk)
        end
      end
    end

    def find_date_by_id id
      self.dates.find id
    end

    def destroy_date date
      date.destroy
    end

    def update_in_out date, in_out
      if in_out != date.in_out
        date.update_attributes({in_out: in_out})
      end
    end

    def find_period_by_id id
      self.periods.find id
    end

    def build_period
      periods.build
    end

    def destroy_period period
      period.destroy
    end

    def self.state_permited_attributes item
      item.slice('comment', 'color').to_hash
    end

    def self.start_validity_period
      [Chouette::TimeTable.minimum(:start_date)].compact.min
    end
    def self.end_validity_period
      [Chouette::TimeTable.maximum(:end_date)].compact.max
    end

    def add_exclude_date(in_out, date)
      self.dates.create!({in_out: in_out, date: date})
    end

    def actualize
      self.dates.clear
      self.periods.clear
      from = self.calendar.convert_to_time_table
      self.dates   = from.dates
      self.periods = from.periods
      self.save
    end

    def save_shortcuts
        shortcuts_update
        self.update_column(:start_date, start_date)
        self.update_column(:end_date, end_date)
    end

    def shortcuts_update(date=nil)
      dates_array = bounding_dates
      #if new_record?
        if dates_array.empty?
          self.start_date=nil
          self.end_date=nil
        else
          self.start_date=dates_array.min
          self.end_date=dates_array.max
        end
      #else
      # if dates_array.empty?
      #   update_attributes :start_date => nil, :end_date => nil
      # else
      #   update_attributes :start_date => dates_array.min, :end_date => dates_array.max
      # end
      #end
    end

    def validity_out_from_on?(expected_date)
      return false unless self.end_date
      self.end_date <= expected_date
    end

    def validity_out_between?(starting_date, ending_date)
      return false unless self.start_date
      starting_date < self.end_date  &&
        self.end_date <= ending_date
    end
    def self.validity_out_from_on?(expected_date,limit=0)
      if limit==0
        Chouette::TimeTable.where("end_date <= ?", expected_date)
      else
        Chouette::TimeTable.where("end_date <= ?", expected_date).limit( limit)
      end
    end
    def self.validity_out_between?(start_date, end_date,limit=0)
      if limit==0
        Chouette::TimeTable.where( "? < end_date", start_date).where( "end_date <= ?", end_date)
      else
        Chouette::TimeTable.where( "? < end_date", start_date).where( "end_date <= ?", end_date).limit( limit)
      end
    end

    # Return days which intersects with the time table dates and periods
    def intersects(days)
      [].tap do |intersect_days|
        days.each do |day|
          intersect_days << day if include_day?(day)
        end
      end
    end

    def include_day?(day)
      include_in_dates?(day) || include_in_periods?(day)
    end

    def include_in_dates?(day)
      self.dates.any?{ |d| d.date === day && d.in_out == true }
    end

    def excluded_date?(day)
      self.dates.any?{ |d| d.date === day && d.in_out == false }
    end

    def include_in_periods?(day)
      self.periods.any?{ |period| period.period_start <= day &&
                                  day <= period.period_end &&
                                  valid_days.include?(day.cwday) &&
                                  ! excluded_date?(day) }
    end

    def include_in_overlap_dates?(day)
      return false if self.excluded_date?(day)

      counter = self.dates.select{ |d| d.date === day}.size + self.periods.select{ |period| period.period_start <= day && day <= period.period_end && valid_days.include?(day.cwday) }.size
      counter <= 1 ? false : true
    end

    def periods_max_date
      return nil if self.periods.empty?

      min_start = self.periods.map(&:period_start).compact.min
      max_end = self.periods.map(&:period_end).compact.max
      result = nil

      if max_end && min_start
        max_end.downto( min_start) do |date|
          if self.valid_days.include?(date.cwday) && !self.excluded_date?(date)
              result = date
              break
          end
        end
      end
      result
    end
    def periods_min_date
      return nil if self.periods.empty?

      min_start = self.periods.map(&:period_start).compact.min
      max_end = self.periods.map(&:period_end).compact.max
      result = nil

      if max_end && min_start
        min_start.upto(max_end) do |date|
          if self.valid_days.include?(date.cwday) && !self.excluded_date?(date)
              result = date
              break
          end
        end
      end
      result
    end
    def bounding_dates
      bounding_min = self.dates.select{|d| d.in_out}.map(&:date).compact.min
      bounding_max = self.dates.select{|d| d.in_out}.map(&:date).compact.max

      unless self.periods.empty?
        bounding_min = periods_min_date if periods_min_date &&
            (bounding_min.nil? || (periods_min_date < bounding_min))

        bounding_max = periods_max_date if periods_max_date &&
            (bounding_max.nil? || (bounding_max < periods_max_date))
      end
      [bounding_min, bounding_max].compact
    end

    def effective_days_of_period(period,valid_days=self.valid_days)
      days = []
        period.period_start.upto(period.period_end) do |date|
          if valid_days.include?(date.cwday) && !self.excluded_date?(date)
              days << date
          end
        end
      days
    end

    def effective_days(valid_days=self.valid_days)
      days=self.effective_days_of_periods(valid_days)
      self.dates.each do |d|
        days |= [d.date] if d.in_out
      end
      days.sort
    end

    def effective_days_of_periods(valid_days=self.valid_days)
      days = []
      self.periods.each { |p| days |= self.effective_days_of_period(p,valid_days)}
      days.sort
    end

    def clone_periods
      periods = []
      self.periods.each { |p| periods << p.copy}
      periods.sort_by(&:period_start)
    end

    def included_days
      days = []
      self.dates.each do |d|
        days |= [d.date] if d.in_out
      end
      days.sort
    end

    def excluded_days
      days = []
      self.dates.each do |d|
        days |= [d.date] unless d.in_out
      end
      days.sort
    end

    def create_date in_out:, date:
      self.dates.create in_out: in_out, date: date
    end

    def saved_dates
      Hash[self.dates.collect{ |d| [d.id, d.date]}]
    end

    def all_dates
      dates
    end

    # produce a copy of periods without anyone overlapping or including another
    def optimize_overlapping_periods
      periods = self.clone_periods
      optimized = []
      i=0
      while i < periods.length
        p1 = periods[i]
        optimized << p1
        j= i+1
        while j < periods.length
          p2 = periods[j]
          if p1.contains? p2
            periods.delete p2
          elsif p1.overlap? p2
            p1.period_start = [p1.period_start,p2.period_start].min
            p1.period_end = [p1.period_end,p2.period_end].max
            periods.delete p2
          else
            j += 1
          end
        end
        i+= 1
      end
      optimized.sort { |a,b| a.period_start <=> b.period_start}
    end

    # add a peculiar day or switch it from excluded to included
    def add_included_day(d)
      if self.excluded_date?(d)
        self.dates.each do |date|
          if date.date === d
            date.in_out = true
          end
        end
      elsif !self.include_in_dates?(d)
        self.dates << Chouette::TimeTableDate.new(:date => d, :in_out => true)
      end
    end

    # merge effective days from another timetable
    def merge!(another_tt)
      transaction do
        days = [].tap do |array|
          array.push(*self.effective_days, *another_tt.effective_days)
          array.uniq!
        end

        self.dates.clear
        self.periods.clear

        days.each do |day|
          self.dates << Chouette::TimeTableDate.new(date: day, in_out: true)
        end
        self.save!
      end
      self.convert_continuous_dates_to_periods
    end

    def included_days_in_dates_and_periods
      in_day  = self.dates.select {|d| d.in_out }.map(&:date)
      out_day = self.dates.select {|d| !d.in_out }.map(&:date)

      in_periods = self.periods.map{|p| (p.period_start..p.period_end).to_a }.flatten
      days = in_periods + in_day
      days -= out_day
      days
    end

    # keep common dates with another_tt
    def intersect!(another_tt)
      transaction do
        days = [].tap do |array|
          array.push(*self.effective_days)
          array.delete_if {|day| !another_tt.effective_days.include?(day) }
          array.uniq!
        end

        self.dates.clear
        self.periods.clear

        days.sort.each do |d|
          self.dates << Chouette::TimeTableDate.new(:date => d, :in_out => true)
        end
        self.save!
      end
      self.convert_continuous_dates_to_periods
    end

    # remove common dates with another_tt
    def disjoin!(another_tt)
      transaction do
        days = [].tap do |array|
          array.push(*self.effective_days)
          array.delete_if {|day| another_tt.effective_days.include?(day) }
          array.uniq!
        end

        self.dates.clear
        self.periods.clear

        days.sort.each do |d|
          self.dates << Chouette::TimeTableDate.new(:date => d, :in_out => true)
        end
        self.save!
      end
      self.convert_continuous_dates_to_periods
    end

    def duplicate
      tt = self.deep_clone :include => [:periods, :dates], :except => [:object_version, :objectid]
      tt.tag_list.add(*self.tag_list) unless self.tag_list.empty?
      tt.created_from = self
      tt.comment      = I18n.t("activerecord.copy", :name => self.comment)
      tt
    end

    def intersect_periods!(mask_periods)
      dates.each do |date|
        unless mask_periods.any? { |p| p.include? date.date }
          dates.delete date
        end
      end

      periods.each do |period|
        mask_periods_with_common_part = mask_periods.select { |p| p.intersect? period.range }

        if mask_periods_with_common_part.empty?
          self.periods.delete period
        else
          mask_periods_with_common_part.each do |mask_period|
            intersection = (mask_period & period.range)
            period.period_start, period.period_end = intersection.begin, intersection.end
          end
        end
      end
    end

    def remove_periods!(removed_periods)
      dates.each do |date|
        if removed_periods.any? { |p| p.include? date.date }
          dates.delete date
        end
      end

      periods.each do |period|
        modified_ranges = removed_periods.inject([period.range]) do |period_ranges, removed_period|
          period_ranges.map { |p| p.remove removed_period }.flatten
        end

        unless modified_ranges.empty?
          modified_ranges.each_with_index do |modified_range, index|
            new_period = index == 0 ? period : periods.build

            new_period.period_start, new_period.period_end =
                                     modified_range.min, modified_range.max
          end
        else
          periods.delete period
        end
      end
    end

    def empty?
      dates.empty? && periods.empty?
    end

  end
end