offers.go

// Copyright 2021-present Airheart, Inc. All rights reserved.
// This source code is licensed under the Apache 2.0 license found
// in the LICENSE file in the root directory of this source tree.

package duffel

import (
	"context"
	"fmt"
	"net/url"
	"strings"
	"time"

	"github.com/bojanz/currency"
)

const offerIDPrefix = "off_"
const offerRequestIDPrefix = "orq_"

type (
	OfferClient interface {
		UpdateOfferPassenger(ctx context.Context, offerRequestID, passengerID string, input PassengerUpdateInput) (*OfferRequestPassenger, error)
		ListOffers(ctx context.Context, reqId string, options ...ListOffersParams) *Iter[Offer]
		GetOffer(ctx context.Context, id string, params ...GetOfferParams) (*Offer, error)
	}

	Offer struct {
		ID                                    string                  `json:"id"`
		LiveMode                              bool                    `json:"live_mode"`
		CreatedAt                             time.Time               `json:"created_at"`
		UpdatedAt                             time.Time               `json:"updated_at"`
		ExpiresAt                             time.Time               `json:"expires_at"`
		TotalEmissionsKg                      string                  `json:"total_emissions_kg"`
		RawTotalCurrency                      string                  `json:"total_currency"`
		RawTotalAmount                        string                  `json:"total_amount"`
		RawTaxAmount                          string                  `json:"tax_amount"`
		RawTaxCurrency                        string                  `json:"tax_currency"`
		RawBaseAmount                         string                  `json:"base_amount"`
		RawBaseCurrency                       string                  `json:"base_currency"`
		Owner                                 Airline                 `json:"owner"`
		Slices                                []Slice                 `json:"slices"`
		Passengers                            []OfferRequestPassenger `json:"passengers"`
		Partial                               bool                    `json:"partial"`
		PassengerIdentityDocumentsRequired    bool                    `json:"passenger_identity_documents_required"`
		AllowedPassengerIdentityDocumentTypes []string                `json:"allowed_passenger_identity_document_types"`
		PaymentRequirements                   OfferPaymentRequirement `json:"payment_requirements"`
		AvailableServices                     []AvailableService      `json:"available_services"`
		Conditions                            Conditions              `json:"conditions"`
	}

	AvailableService struct {
		// Duffel's unique identifier for service
		ID               string                   `json:"id"`
		MaximumQuantity  int                      `json:"maximum_quantity"`
		Metadata         AvailableServiceMetadata `json:"metadata"`
		PassengerIDs     []string                 `json:"passenger_ids"`
		SegmentIDs       []string                 `json:"segment_ids"`
		RawTotalAmount   string                   `json:"total_amount"`
		RawTotalCurrency string                   `json:"total_currency"`

		// Possible values: "baggage"
		Type string `json:"type"`
	}

	AvailableServiceMetadata struct {
		MaximumDepthCM  int `json:"maximum_depth_cm,omitempty"`
		MaximumHeightCM int `json:"maximum_height_cm,omitempty"`
		MaximumLengthCM int `json:"maximum_length_cm,omitempty"`
		MaximumWeightKg int `json:"maximum_weight_kg,omitempty"`
		// Possible values: "checked", "carry_on"
		Type string `json:"type"`
	}

	OfferPaymentRequirement struct {
		RequiresInstantPayment  bool      `json:"requires_instant_payment"`
		PriceGuaranteeExpiresAt *DateTime `json:"price_guarantee_expires_at"`
		PaymentRequiredBy       *DateTime `json:"payment_required_by"`
	}

	ListOffersSortParam string

	ListOffersParams struct {
		Sort           ListOffersSortParam `url:"sort,omitempty"`
		MaxConnections int                 `url:"max_connections,omitempty"`
	}

	GetOfferParams struct {
		ReturnAvailableServices bool
	}
)

const (
	ListOffersSortTotalAmount   ListOffersSortParam = "total_amount"
	ListOffersSortTotalDuration ListOffersSortParam = "total_duration"
)

// UpdateOfferPassenger updates a single offer passenger.
func (a *API) UpdateOfferPassenger(ctx context.Context, offerRequestID, passengerID string, input PassengerUpdateInput) (*OfferRequestPassenger, error) {
	url := fmt.Sprintf("/air/offers/%s/passengers/%s", offerRequestID, passengerID)
	return newRequestWithAPI[PassengerUpdateInput, OfferRequestPassenger](a).Patch(url, &input).Single(ctx)
}

// ListOffers lists all the offers for an offer request. Returns an iterator.
func (a *API) ListOffers(ctx context.Context, offerRequestID string, options ...ListOffersParams) *Iter[Offer] {
	if offerRequestID == "" {
		return ErrIter[Offer](fmt.Errorf("offerRequestId param is required"))
	} else if !strings.HasPrefix(offerRequestID, offerRequestIDPrefix) {
		return ErrIter[Offer](fmt.Errorf("offerRequestId should begin with %s", offerRequestIDPrefix))
	}

	return newRequestWithAPI[ListOffersParams, Offer](a).Get("/air/offers").
		WithParam("offer_request_id", offerRequestID).
		WithParams(normalizeParams(options)...).
		Iter(ctx)
}

// GetOffer gets a single offer by ID.
func (a *API) GetOffer(ctx context.Context, offerID string, params ...GetOfferParams) (*Offer, error) {
	if !strings.HasPrefix(offerID, offerIDPrefix) {
		return nil, fmt.Errorf("offerID should begin with %s", offerIDPrefix)
	}

	return newRequestWithAPI[GetOfferParams, Offer](a).
		Getf("/air/offers/%s", offerID).
		WithParams(normalizeParams(params)...).
		Single(ctx)
}

func (o ListOffersParams) Encode(q url.Values) error {
	if o.Sort != "" {
		q.Set("sort", string(o.Sort))
	}

	if o.MaxConnections != 0 {
		q.Set("max_connections", fmt.Sprintf("%d", o.MaxConnections))
	}

	return nil
}

func (o GetOfferParams) Encode(q url.Values) error {
	if o.ReturnAvailableServices {
		q.Set("return_available_services", "true")
	}
	return nil
}

func (o *Offer) BaseAmount() currency.Amount {
	amount, err := currency.NewAmount(o.RawBaseAmount, o.RawBaseCurrency)
	if err != nil {
		return currency.Amount{}
	}
	return amount
}
func (o *Offer) TotalAmount() currency.Amount {
	amount, err := currency.NewAmount(o.RawTotalAmount, o.RawTotalCurrency)
	if err != nil {
		return currency.Amount{}
	}
	return amount
}

func (o *Offer) TaxAmount() currency.Amount {
	amount, err := currency.NewAmount(o.RawTaxAmount, o.RawTaxCurrency)
	if err != nil {
		return currency.Amount{}
	}
	return amount
}

// Less will sort ascending by total amount
func (o Offers) Less(i, j int) bool {
	cmp, err := o[i].TotalAmount().Cmp(o[j].TotalAmount())
	if err != nil {
		return false
	}
	return cmp < 0
}

func (o Offers) Swap(i, j int) {
	o[i], o[j] = o[j], o[i]
}

func (o Offers) Len() int {
	return len(o)
}

var _ OfferClient = (*API)(nil)