package warehouses

import (
	"errors"
	"net/http"
	"strconv"

	"github.com/TaruLab/keluargamart-backend/pkg/httpresponse"
	"github.com/TaruLab/keluargamart-backend/pkg/logger"
	"github.com/TaruLab/keluargamart-backend/pkg/middleware"
	"github.com/go-chi/chi/v5"
)

// Handler binds the warehouses service to HTTP. Methods are exported so the
// router can attach RequirePermission per route in main.
type Handler struct {
	svc *Service
}

func NewHandler(svc *Service) *Handler {
	return &Handler{svc: svc}
}

func (h *Handler) List(w http.ResponseWriter, r *http.Request) {
	q := r.URL.Query()
	page, per := queryInt(q.Get("page")), queryInt(q.Get("per_page"))
	search := q.Get("search")
	if search == "" {
		search = q.Get("q")
	}
	list, total, err := h.svc.List(r.Context(), page, per, search)
	if err != nil {
		httpresponse.Internal(w, middleware.RequestIDFrom(r.Context()), logger.FromContext(r.Context()), err)
		return
	}
	httpresponse.OKPaginated(w, http.StatusOK, middleware.RequestIDFrom(r.Context()), list, norm(page), norm(per), total)
}

// Options serves the slim warehouse list for checkout pickers. Mounted
// bearer-only (any authenticated user), no inventory.warehouses.view.
func (h *Handler) Options(w http.ResponseWriter, r *http.Request) {
	opts, err := h.svc.Options(r.Context())
	if err != nil {
		httpresponse.Internal(w, middleware.RequestIDFrom(r.Context()), logger.FromContext(r.Context()), err)
		return
	}
	httpresponse.OK(w, http.StatusOK, middleware.RequestIDFrom(r.Context()), opts)
}

func (h *Handler) Create(w http.ResponseWriter, r *http.Request) {
	var in Input
	if !decode(w, r, &in) {
		return
	}
	wh, err := h.svc.Create(r.Context(), in)
	if err != nil {
		respondErr(w, r, err)
		return
	}
	httpresponse.OK(w, http.StatusCreated, middleware.RequestIDFrom(r.Context()), wh)
}

func (h *Handler) Get(w http.ResponseWriter, r *http.Request) {
	wh, err := h.svc.store.ByID(r.Context(), pathID(r))
	if err != nil {
		respondErr(w, r, err)
		return
	}
	httpresponse.OK(w, http.StatusOK, middleware.RequestIDFrom(r.Context()), wh)
}

func (h *Handler) Update(w http.ResponseWriter, r *http.Request) {
	var in Input
	if !decode(w, r, &in) {
		return
	}
	wh, err := h.svc.Update(r.Context(), pathID(r), in)
	if err != nil {
		respondErr(w, r, err)
		return
	}
	httpresponse.OK(w, http.StatusOK, middleware.RequestIDFrom(r.Context()), wh)
}

func (h *Handler) Delete(w http.ResponseWriter, r *http.Request) {
	if err := h.svc.Delete(r.Context(), pathID(r)); err != nil {
		respondErr(w, r, err)
		return
	}
	w.WriteHeader(http.StatusNoContent)
}

func pathID(r *http.Request) int64 {
	id, _ := strconv.ParseInt(chi.URLParam(r, "id"), 10, 64)
	return id
}

func decode(w http.ResponseWriter, r *http.Request, dst any) bool {
	return httpresponse.DecodeJSON(w, r, middleware.RequestIDFrom(r.Context()), dst)
}

func respondErr(w http.ResponseWriter, r *http.Request, err error) {
	rid := middleware.RequestIDFrom(r.Context())
	switch {
	case errors.Is(err, ErrNotFound):
		httpresponse.Error(w, http.StatusNotFound, rid, httpresponse.CodeNotFound, "Not found", nil)
	case err != nil:
		httpresponse.SafeError(w, rid, logger.FromContext(r.Context()), http.StatusBadRequest, httpresponse.CodeValidation, err)
	}
}

func queryInt(s string) int {
	n, _ := strconv.Atoi(s)
	return n
}

func norm(n int) int {
	if n < 1 {
		return 1
	}
	return n
}