# Handle order management and checkout process
#
# This controller manages the order lifecycle from checkout to payment completion
# Orders group multiple tickets together for better transaction management
class OrdersController < ApplicationController
  before_action :authenticate_user!
  before_action :set_order, only: [:show, :checkout, :retry_payment, :increment_payment_attempt]
  before_action :set_event, only: [:new, :create]

  # Display new order form with name collection
  #
  # On this page user can see order summary and complete the tickets details 
  # (first name and last name) for each ticket ordered
  def new
    @cart_data = session[:pending_cart] || {}

    if @cart_data.empty?
      redirect_to event_path(@event.slug, @event), alert: "Veuillez d'abord sélectionner vos billets sur la page de l'événement"
      return
    end

    # Build list of tickets requiring names
    @tickets_needing_names = []
    @cart_data.each do |ticket_type_id, item|
      ticket_type = @event.ticket_types.find_by(id: ticket_type_id)
      next unless ticket_type

      quantity = item["quantity"].to_i
      next if quantity <= 0

      quantity.times do |i|
        @tickets_needing_names << {
          ticket_type_id: ticket_type.id,
          ticket_type_name: ticket_type.name,
          ticket_type_price: ticket_type.price_cents,
          index: i
        }
      end
    end
  end

  # Create a new order with tickets
  #
  # Here a new order is created with associated tickets in draft state.
  # When user is ready they can proceed to payment via the order checkout
  def create
    @cart_data = session[:pending_cart] || {}

    if @cart_data.empty?
      redirect_to event_path(@event.slug, @event), alert: "Aucun billet sélectionné"
      return
    end

    success = false
    
    ActiveRecord::Base.transaction do
      @order = current_user.orders.create!(event: @event, status: "draft")

      order_params[:tickets_attributes]&.each do |index, ticket_attrs|
        next if ticket_attrs[:first_name].blank? || ticket_attrs[:last_name].blank?

        ticket_type = @event.ticket_types.find(ticket_attrs[:ticket_type_id])
        
        ticket = @order.tickets.build(
          ticket_type: ticket_type,
          first_name: ticket_attrs[:first_name],
          last_name: ticket_attrs[:last_name],
          status: "draft"
        )

        unless ticket.save
          flash[:alert] = "Erreur lors de la création des billets: #{ticket.errors.full_messages.join(', ')}"
          raise ActiveRecord::Rollback
        end
      end

      if @order.tickets.present?
        @order.calculate_total!
        success = true
      else
        flash[:alert] = "Aucun billet valide créé"
        raise ActiveRecord::Rollback
      end
    end
    
    # Handle redirects outside transaction
    if success
      session[:draft_order_id] = @order.id
      session.delete(:pending_cart)
      redirect_to checkout_order_path(@order)
    else
      redirect_to event_order_new_path(@event.slug, @event.id)
    end
  rescue => e
    error_message = e.message.present? ? e.message : "Erreur inconnue"
    flash[:alert] = "Une erreur est survenue: #{error_message}"
    redirect_to event_order_new_path(@event.slug, @event.id)
  end

  # Display order summary
  #
  #
  def show
    @tickets = @order.tickets.includes(:ticket_type)
  end

  # Display payment page for an order
  #
  # Display a summary of all tickets in the order and permit user
  # to proceed to payment via Stripe
  def checkout
    # Handle expired orders
    if @order.expired?
      @order.expire_if_overdue!
      return redirect_to event_path(@order.event.slug, @order.event),
        alert: "Votre commande a expiré. Veuillez recommencer."
    end

    @tickets = @order.tickets.includes(:ticket_type)
    @total_amount = @order.total_amount_cents
    @expiring_soon = @order.expiring_soon?

    # Create Stripe checkout session if Stripe is configured
    if Rails.application.config.stripe[:secret_key].present?
      begin
        @checkout_session = create_stripe_session
      rescue => e
        error_message = e.message.present? ? e.message : "Erreur Stripe inconnue"
        Rails.logger.error "Stripe checkout session creation failed: #{error_message}"
        flash[:alert] = "Erreur lors de la création de la session de paiement"
      end
    end
  end

  # Increment payment attempt - called via AJAX when user clicks pay button
  def increment_payment_attempt
    @order.increment_payment_attempt!
    render json: { success: true, attempts: @order.payment_attempts }
  end

  # Allow users to retry payment for failed/cancelled payments
  def retry_payment
    unless @order.can_retry_payment?
      redirect_to event_path(@order.event.slug, @order.event),
                 alert: "Cette commande ne peut plus être payée"
      return
    end

    redirect_to order_checkout_path(@order)
  end

  # Handle successful payment
  def payment_success
    session_id = params[:session_id]

    # Check if Stripe is properly configured
    stripe_configured = Rails.application.config.stripe[:secret_key].present?
    Rails.logger.debug "Payment success - Stripe configured: #{stripe_configured}"

    unless stripe_configured
      redirect_to dashboard_path, alert: "Le système de paiement n'est pas correctement configuré. Veuillez contacter l'administrateur."
      return
    end

    begin
      stripe_session = Stripe::Checkout::Session.retrieve(session_id)

      if stripe_session.payment_status == "paid"
        # Get order_id from session metadata
        order_id = stripe_session.metadata["order_id"]

        unless order_id.present?
          redirect_to dashboard_path, alert: "Informations de commande manquantes"
          return
        end

        # Find and update the order
        @order = current_user.orders.includes(tickets: :ticket_type).find(order_id)
        @order.mark_as_paid!

        # Send confirmation emails
        @order.tickets.each do |ticket|
          begin
            TicketMailer.purchase_confirmation(ticket).deliver_now
          rescue => e
            Rails.logger.error "Failed to send confirmation email for ticket #{ticket.id}: #{e.message}"
            # Don't fail the entire payment process due to email/PDF generation issues
          end
        end

        # Clear session data
        session.delete(:pending_cart)
        session.delete(:ticket_names)
        session.delete(:draft_order_id)

        render "payment_success"
      else
        redirect_to dashboard_path, alert: "Le paiement n'a pas été complété avec succès"
      end
    rescue Stripe::StripeError => e
      error_message = e.message.present? ? e.message : "Erreur Stripe inconnue"
      redirect_to dashboard_path, alert: "Erreur lors du traitement de votre confirmation de paiement : #{error_message}"
    rescue => e
      error_message = e.message.present? ? e.message : "Erreur inconnue"
      Rails.logger.error "Payment success error: #{e.class} - #{error_message}"
      redirect_to dashboard_path, alert: "Une erreur inattendue s'est produite : #{error_message}"
    end
  end

  # Handle payment failure/cancellation
  def payment_cancel
    order_id = session[:draft_order_id]

    if order_id.present?
      order = current_user.orders.find_by(id: order_id, status: "draft")

      if order&.can_retry_payment?
        redirect_to order_checkout_path(order),
                   alert: "Le paiement a été annulé. Vous pouvez réessayer."
      else
        session.delete(:draft_order_id)
        redirect_to dashboard_path, alert: "Le paiement a été annulé et votre commande a expiré."
      end
    else
      redirect_to dashboard_path, alert: "Le paiement a été annulé"
    end
  end

  private

  def set_order
    @order = current_user.orders.includes(:tickets, :event).find(params[:id])
  rescue ActiveRecord::RecordNotFound
    redirect_to dashboard_path, alert: "Commande non trouvée"
  end

  def set_event
    @event = Event.includes(:ticket_types).find(params[:id])
  rescue ActiveRecord::RecordNotFound
    redirect_to events_path, alert: "Événement non trouvé"
  end

  def order_params
    params.permit(tickets_attributes: [ :ticket_type_id, :first_name, :last_name ])
  end

  def create_stripe_session
    line_items = @order.tickets.map do |ticket|
      {
        price_data: {
          currency: "eur",
          product_data: {
            name: "#{@order.event.name} - #{ticket.ticket_type.name}",
            description: ticket.ticket_type.description
          },
          unit_amount: ticket.price_cents
        },
        quantity: 1
      }
    end

    Stripe::Checkout::Session.create(
      payment_method_types: ["card"],
      line_items: line_items,
      mode: "payment",
      success_url: order_payment_success_url + "?session_id={CHECKOUT_SESSION_ID}",
      cancel_url: order_payment_cancel_url,
      metadata: {
        order_id: @order.id,
        user_id: current_user.id
      }
    )
  end
end