package main

import (
	"bytes"
	"encoding/json"
	"fmt"
	"log"
	"net/http"
	"os"
	"strconv"
	"strings"
	"time"

	messages "git.tornberg.me/go-cart-actor/proto"
	"golang.org/x/exp/rand"
)

type PoolServer struct {
	pod_name string
	pool     GrainPool
}

func NewPoolServer(pool GrainPool, pod_name string) *PoolServer {
	return &PoolServer{
		pod_name: pod_name,
		pool:     pool,
	}
}

func (s *PoolServer) HandleGet(w http.ResponseWriter, r *http.Request) error {
	id := r.PathValue("id")

	data, err := s.pool.Get(ToCartId(id))
	if err != nil {
		return err
	}
	return s.WriteResult(w, data)
}

func (s *PoolServer) HandleAddSku(w http.ResponseWriter, r *http.Request) error {
	id := r.PathValue("id")
	sku := r.PathValue("sku")
	data, err := s.pool.Process(ToCartId(id), Message{
		Type:    AddRequestType,
		Content: &messages.AddRequest{Sku: sku, Quantity: 1},
	})
	if err != nil {
		return err
	}
	return s.WriteResult(w, data)
}

func ErrorHandler(fn func(w http.ResponseWriter, r *http.Request) error) func(w http.ResponseWriter, r *http.Request) {
	return func(w http.ResponseWriter, r *http.Request) {
		err := fn(w, r)
		if err != nil {
			log.Printf("Server error, not remote error: %v\n", err)
			w.WriteHeader(http.StatusInternalServerError)
			w.Write([]byte(err.Error()))
		}
	}
}

func (s *PoolServer) WriteResult(w http.ResponseWriter, result *FrameWithPayload) error {
	w.Header().Set("Content-Type", "application/json")
	w.Header().Set("X-Pod-Name", s.pod_name)
	w.Header().Set("Access-Control-Allow-Origin", "https://tornberg.me")
	if result.StatusCode != 200 {
		log.Printf("Call error: %d\n", result.StatusCode)
		if result.StatusCode >= 200 && result.StatusCode < 600 {
			w.WriteHeader(int(result.StatusCode))
		} else {
			w.WriteHeader(http.StatusInternalServerError)
		}
		w.Write([]byte(result.Payload))
		return nil
	}
	w.WriteHeader(http.StatusOK)
	_, err := w.Write(result.Payload)
	return err
}

func (s *PoolServer) HandleDeleteItem(w http.ResponseWriter, r *http.Request) error {
	id := r.PathValue("id")
	itemIdString := r.PathValue("itemId")
	itemId, err := strconv.Atoi(itemIdString)
	if err != nil {
		return err
	}
	data, err := s.pool.Process(ToCartId(id), Message{
		Type:    RemoveItemType,
		Content: &messages.RemoveItem{Id: int64(itemId)},
	})
	if err != nil {
		return err
	}
	return s.WriteResult(w, data)
}

type SetDelivery struct {
	Provider string  `json:"provider"`
	Items    []int64 `json:"items"`
}

func (s *PoolServer) HandleSetDelivery(w http.ResponseWriter, r *http.Request) error {
	id := r.PathValue("id")
	delivery := SetDelivery{}
	err := json.NewDecoder(r.Body).Decode(&delivery)
	if err != nil {
		return err
	}
	data, err := s.pool.Process(ToCartId(id), Message{
		Type: SetDeliveryType,
		Content: &messages.SetDelivery{
			Provider: delivery.Provider,
			Items:    delivery.Items,
		},
	})
	if err != nil {
		return err
	}
	return s.WriteResult(w, data)
}

func (s *PoolServer) HandleSetPickupPoint(w http.ResponseWriter, r *http.Request) error {
	id := r.PathValue("id")
	deliveryIdString := r.PathValue("deliveryId")
	deliveryId, err := strconv.Atoi(deliveryIdString)
	if err != nil {
		return err
	}
	pickupPoint := messages.PickupPoint{}
	err = json.NewDecoder(r.Body).Decode(&pickupPoint)
	if err != nil {
		return err
	}
	reply, err := s.pool.Process(ToCartId(id), Message{
		Type: SetPickupPointType,
		Content: &messages.SetPickupPoint{
			DeliveryId: int64(deliveryId),
			Id:         pickupPoint.Id,
			Name:       pickupPoint.Name,
			Address:    pickupPoint.Address,
			City:       pickupPoint.City,
			Zip:        pickupPoint.Zip,
			Country:    pickupPoint.Country,
		},
	})
	if err != nil {
		return err
	}
	return s.WriteResult(w, reply)
}

func (s *PoolServer) HandleRemoveDelivery(w http.ResponseWriter, r *http.Request) error {
	id := r.PathValue("id")
	deliveryIdString := r.PathValue("deliveryId")
	deliveryId, err := strconv.Atoi(deliveryIdString)
	if err != nil {
		return err
	}
	reply, err := s.pool.Process(ToCartId(id), Message{
		Type:    RemoveDeliveryType,
		Content: &messages.RemoveDelivery{Id: int64(deliveryId)},
	})
	if err != nil {
		return err
	}
	return s.WriteResult(w, reply)
}

func (s *PoolServer) HandleQuantityChange(w http.ResponseWriter, r *http.Request) error {
	id := r.PathValue("id")

	changeQuantity := messages.ChangeQuantity{}
	err := json.NewDecoder(r.Body).Decode(&changeQuantity)
	if err != nil {
		return err
	}
	reply, err := s.pool.Process(ToCartId(id), Message{
		Type:    ChangeQuantityType,
		Content: &changeQuantity,
	})
	if err != nil {
		return err
	}
	return s.WriteResult(w, reply)
}

func (s *PoolServer) HandleAddRequest(w http.ResponseWriter, r *http.Request) error {
	id := r.PathValue("id")

	addRequest := messages.AddRequest{}
	err := json.NewDecoder(r.Body).Decode(&addRequest)
	if err != nil {
		return err
	}
	reply, err := s.pool.Process(ToCartId(id), Message{
		Type:    AddRequestType,
		Content: &addRequest,
	})
	if err != nil {
		return err
	}
	return s.WriteResult(w, reply)
}

var (
	APIUsername = os.Getenv("KLARNA_API_USERNAME")
	APIPassword = os.Getenv("KLARNA_API_PASSWORD")
)

func (s *PoolServer) HandleCheckout(w http.ResponseWriter, r *http.Request) error {
	id := r.PathValue("id")

	reply, err := s.pool.Process(ToCartId(id), Message{
		Type: CreateCheckoutOrderType,
		Content: &messages.CreateCheckoutOrder{
			Terms:        "https://tornberg.me/terms",
			Checkout:     "https://tornberg.me/checkout",
			Confirmation: "https://tornberg.me/confirmation",
			Push:         "https://cart.tornberg.me/push",
		},
	})
	if err != nil {
		return err
	}
	if reply.StatusCode != 200 {
		return s.WriteResult(w, reply)
	}

	req, err := http.NewRequest("POST", "https://api.playground.klarna.com/checkout/v3/orders", bytes.NewReader(reply.Payload))
	if err != nil {
		return err
	}

	req.Header.Add("Content-Type", "application/json")
	req.SetBasicAuth(APIUsername, APIPassword)

	res, err := http.DefaultClient.Do(req)
	if nil != err {
		return err
	}

	buf := new(bytes.Buffer)
	buf.ReadFrom(res.Body)
	w.Header().Set("Content-Type", "application/json")
	w.Header().Set("X-Pod-Name", s.pod_name)
	w.Header().Set("Access-Control-Allow-Origin", "https://tornberg.me")
	w.WriteHeader(res.StatusCode)

	w.Write(buf.Bytes())
	return nil
}

func NewCartId() CartId {
	id := time.Now().UnixNano() + rand.Int63()

	return ToCartId(fmt.Sprintf("%d", id))
}

func (a *PoolServer) RewritePath(w http.ResponseWriter, r *http.Request) {
	var cartId CartId
	if strings.Contains(r.URL.Path, ".") {
		http.NotFound(w, r)
		return
	}
	cartIdCookie := r.CookiesNamed("cartid")
	if cartIdCookie == nil || len(cartIdCookie) == 0 {
		cartId = NewCartId()
		http.SetCookie(w, &http.Cookie{
			Name:     "cartid",
			Value:    cartId.String(),
			Path:     "/",
			SameSite: http.SameSiteLaxMode,
		})
	} else {
		cartId = ToCartId(cartIdCookie[0].Value)
	}
	adjustedPath := strings.Replace(r.URL.Path, "/cart", "", 1)
	location := fmt.Sprintf("/cart/%s%s", cartId, strings.TrimRight(adjustedPath, "/"))
	w.Header().Set("Location", location)
	w.WriteHeader(http.StatusMovedPermanently)
}

func (s *PoolServer) Serve() *http.ServeMux {
	mux := http.NewServeMux()
	mux.HandleFunc("/", s.RewritePath)
	mux.HandleFunc("GET /{id}", ErrorHandler(s.HandleGet))
	mux.HandleFunc("GET /{id}/add/{sku}", ErrorHandler(s.HandleAddSku))
	mux.HandleFunc("POST /{id}", ErrorHandler(s.HandleAddRequest))
	mux.HandleFunc("DELETE /{id}/{itemId}", ErrorHandler(s.HandleDeleteItem))
	mux.HandleFunc("PUT /{id}", ErrorHandler(s.HandleQuantityChange))
	mux.HandleFunc("POST /{id}/delivery", ErrorHandler(s.HandleSetDelivery))
	mux.HandleFunc("DELETE /{id}/delivery/{deliveryId}", ErrorHandler(s.HandleRemoveDelivery))
	mux.HandleFunc("PUT /{id}/delivery/{deliveryId}/pickupPoint", ErrorHandler(s.HandleSetPickupPoint))
	mux.HandleFunc("GET /{id}/checkout", ErrorHandler(s.HandleCheckout))

	return mux
}