# app/services/mood_calendar_service.rb
class MoodCalendarService
  def self.generate_calendar(moods, start_date: nil, end_date: Date.current)
    # Preload modes with their image attachments
    mode_ids = moods.joins(:mode).pluck("modes.id").uniq
    modes_by_id = Mode.where(id: mode_ids)
      .with_attached_image
      .index_by(&:id)

    data = moods.joins(:mode)
      .order(:recorded_at)
      .pluck(:recorded_at, "modes.label", "modes.color", "modes.id")
      .map do |recorded_at, label, color, mode_id|
        mode = modes_by_id[mode_id]
        {
          mode: {
            label: label,
            color: color,
            image_url: mode&.image&.attached? ? Rails.application.routes.url_helpers.rails_blob_url(mode.image, only_path: true) : nil
          },
          recorded_at: recorded_at
        }
      end   # Convertir la relation ActiveRecord en tableau de hash

    if data.empty?
      start_date = Date.current
    else
      start_date ||= data.first[:recorded_at].to_date
    end

    if end_date < (start_date + 5.months)
      end_date = start_date + 5.months
    end

    # Convertir en Date si ce sont des DateTime ou Time
    start_date = start_date.to_date
    end_date = end_date&.to_date

    # Grouper par jour et garder le plus récent pour chaque jour
    data_by_date = data.group_by { |d| d[:recorded_at].to_date }
                       .transform_values { |entries| entries.max_by { |e| e[:recorded_at] } }

    # Trouver le dernier mood avant start_date pour initialiser le guess
    last_mode = data.select { |d| d[:recorded_at].to_date < start_date }
                    .max_by { |d| d[:recorded_at] }
                    &.[](:mode)

    # Générer le tableau complet avec tous les jours
    complete_data = (start_date..end_date).map do |date|
      if data_by_date[date]
        last_mode = data_by_date[date][:mode]
        data_by_date[date]
      else
        { mode: nil, recorded_at: date.to_datetime, guess: last_mode }
      end
    end

    # Regrouper par mois avec semaines commençant au premier lundi
    complete_data.group_by { |d| d[:recorded_at].to_date.beginning_of_month }
                 .map do |month_start, month_data|
      first_monday = month_start
      first_monday = first_monday.next_occurring(:monday) unless first_monday.monday?

      next_month_start = month_start.next_month.beginning_of_month
      next_first_monday = next_month_start
      next_first_monday = next_first_monday.next_occurring(:monday) unless next_first_monday.monday?

      month_end = next_first_monday - 1.day

      data_hash = complete_data.index_by { |d| d[:recorded_at].to_date }

      all_days = (first_monday..month_end).map do |date|
        data_hash[date] || { mode: nil, recorded_at: date.to_datetime, guess: nil }
      end

      weeks = all_days.group_by { |d| d[:recorded_at].to_date.beginning_of_week(:monday) }
                      .sort_by { |week_start, _| week_start }
                      .map { |_, week_moods| week_moods }

      {
        month: month_start,
        weeks: weeks
      }
    end
  end
end#