package main

import (
	"encoding/json"
	"net/http"
	"strconv"

	messages "git.tornberg.me/go-cart-actor/proto"
)

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 {
			w.WriteHeader(http.StatusInternalServerError)
			w.Write([]byte(err.Error()))
		}
	}
}

func (s *PoolServer) WriteResult(w http.ResponseWriter, data []byte) error {
	w.Header().Set("Content-Type", "application/json")
	w.Header().Set("X-Pod-Name", s.pod_name)
	w.WriteHeader(http.StatusOK)
	_, err := w.Write(data)
	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) Serve() *http.ServeMux {
	mux := http.NewServeMux()
	mux.HandleFunc("GET /{id}", ErrorHandler(s.HandleGet))
	mux.HandleFunc("GET /{id}/add/{sku}", ErrorHandler(s.HandleAddSku))
	mux.HandleFunc("DELETE /{id}/{itemId}", ErrorHandler(s.HandleDeleteItem))
	mux.HandleFunc("POST /{id}/delivery", ErrorHandler(s.HandleSetDelivery))
	return mux
}