module Api
  module V1
    class DashboardController < BaseController
      def show
        current_user.update_required_matrices!
        entries = current_user.entries.where("date <= ?", Date.current)
        progress = User::PRAKTIKUMSTYPEN.flat_map do |typ|
          User.entry_arten_for(typ).map do |art|
            spent = entries.where(praktikums_typ: typ, entry_art: art).sum("COALESCE(hours, 0) * 60 + COALESCE(minutes, 0)").to_i
            target = current_user.required_hours_for(typ, art).to_f * 60
            remaining = [target - spent, 0].max.to_i
            weekly_target = current_user.weekly_target_for(typ, art).to_f
            dates = entries.where(praktikums_typ: typ, entry_art: art).where("COALESCE(hours, 0) > 0 OR COALESCE(minutes, 0) > 0")
            first_date = dates.minimum(:date)
            last_date = dates.maximum(:date)
            period_end = spent >= target && last_date ? last_date : Date.current
            weeks = first_date ? [[(period_end - first_date).to_i + 1, 7].max / 7.0, 1].max : nil
            actual_weekly = weeks ? ((spent / 60.0) / weeks).round(2) : nil
            estimated_end = weekly_target.positive? && remaining.positive? ? Date.current + (remaining / 60.0 / weekly_target).ceil.weeks : nil
            { typ:, art:, spent_minutes: spent, target_minutes: target.to_i, remaining_minutes: remaining,
              percent: target.positive? ? [(spent / target * 100).round(1), 100].min : 0,
              weekly_target:, actual_weekly:, estimated_end: }
          end
        end
        total_spent = progress.sum { |row| row[:spent_minutes] }
        total_target = progress.sum { |row| row[:target_minutes] }
        render json: { total_minutes: total_spent, target_minutes: total_target, remaining_minutes: [total_target - total_spent, 0].max,
          completed_percent: total_target.positive? ? (total_spent.to_f / total_target * 100).round(1) : 0,
          total_distance_km: current_user.entries.sum(:distance_km), costs_by_year: costs_by_year,
          running_entry: current_user.entries.find_by(end_time: nil, beschreibung: "Timer"),
          mediation_presence_days: current_user.mediation_praesenzmodule_completed,
          mediation_presence_days_required: current_user.mediation_praesenzmodule_required,
          last_entry: current_user.entries.where("date <= ?", Date.current).order(date: :desc).first, progress: }
      end

      private

      def costs_by_year
        years = current_user.entries.pluck(Arel.sql("DISTINCT EXTRACT(YEAR FROM date)::int")).compact.sort.reverse
        km = Entry.total_kilometer_cost_by_year(current_user)
        total = Entry.total_gesamtkosten_by_year(current_user)
        training = Entry.total_fortbildungskosten_by_year(current_user)
        experience = Entry.total_selbsterfahrungskosten_by_year(current_user)
        supervision = Entry.total_supervision_by_year(current_user)
        semester = Entry.total_semesterkosten_by_year(current_user)
        years.map { |year| { year:, kilometer: km[year].to_f, fortbildung: training[year].to_f,
          selbsterfahrung: experience[year].to_f, supervision: supervision[year].to_f,
          semester: semester[year].to_f, total: total[year].to_f } }
      end
    end
  end
end