package httpapi

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

	"git.118im.com/im_team/olons_server/internal/mall"
	"git.118im.com/im_team/olons_server/internal/store"
)

func (a *API) manualProducts(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodGet {
		methodNotAllowed(w, r, http.MethodGet)
		return
	}
	if a.mall == nil {
		writeError(w, r, http.StatusServiceUnavailable, 90001, "SERVICE_UNAVAILABLE", "service unavailable", nil)
		return
	}
	principal, ok := a.authenticateMember(w, r)
	if !ok {
		return
	}
	page, ok := optionalPositiveInt(w, r, "page")
	if !ok {
		writeMallError(w, r, mall.ErrPageInvalid)
		return
	}
	pageSize, ok := optionalPositiveInt(w, r, "page_size")
	if !ok {
		writeMallError(w, r, mall.ErrPageSizeInvalid)
		return
	}
	categoryID, ok := optionalNonNegativeInt64(r.URL.Query().Get("category_id"))
	if !ok {
		writeMallError(w, r, mall.ErrCategoryIDInvalid)
		return
	}
	result, err := a.mall.Products(r.Context(), principal.TenantID, categoryID, page, pageSize)
	if err != nil {
		writeMallError(w, r, err)
		return
	}
	writeSuccess(w, r, result)
}

func (a *API) manualProduct(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodGet {
		methodNotAllowed(w, r, http.MethodGet)
		return
	}
	if a.mall == nil {
		writeError(w, r, http.StatusServiceUnavailable, 90001, "SERVICE_UNAVAILABLE", "service unavailable", nil)
		return
	}
	productIDText := strings.Trim(strings.TrimPrefix(r.URL.Path, "/v1/manual-products/"), "/")
	if productIDText == "" || strings.Contains(productIDText, "/") {
		writeMallError(w, r, mall.ErrProductIDInvalid)
		return
	}
	productID, err := strconv.ParseInt(productIDText, 10, 64)
	if err != nil || productID <= 0 {
		writeMallError(w, r, mall.ErrProductIDInvalid)
		return
	}
	principal, ok := a.authenticateMember(w, r)
	if !ok {
		return
	}
	result, err := a.mall.Product(r.Context(), principal.TenantID, productID)
	if err != nil {
		writeMallError(w, r, err)
		return
	}
	writeSuccess(w, r, result)
}

func optionalNonNegativeInt64(value string) (int64, bool) {
	value = strings.TrimSpace(value)
	if value == "" {
		return 0, true
	}
	parsed, err := strconv.ParseInt(value, 10, 64)
	return parsed, err == nil && parsed >= 0
}

func writeMallError(w http.ResponseWriter, r *http.Request, err error) {
	switch {
	case errors.Is(err, mall.ErrCategoryIDInvalid):
		writeError(w, r, http.StatusBadRequest, 30000, "CATEGORY_ID_INVALID", "validation failed", map[string]any{"field": "category_id"})
	case errors.Is(err, mall.ErrProductIDInvalid):
		writeError(w, r, http.StatusBadRequest, 30000, "PRODUCT_ID_INVALID", "validation failed", map[string]any{"field": "product_id"})
	case errors.Is(err, mall.ErrPageInvalid):
		writeError(w, r, http.StatusBadRequest, 30000, "PAGE_INVALID", "validation failed", map[string]any{"field": "page"})
	case errors.Is(err, mall.ErrPageSizeInvalid):
		writeError(w, r, http.StatusBadRequest, 30000, "PAGE_SIZE_INVALID", "validation failed", map[string]any{"field": "page_size"})
	case errors.Is(err, store.ErrResourceNotFound):
		writeError(w, r, http.StatusNotFound, 30044, "PRODUCT_NOT_FOUND", "manual product not found", nil)
	default:
		writeError(w, r, http.StatusInternalServerError, 90000, reasonInternal, "internal error", nil)
	}
}