pricing: enrich pricelist items with stock and tighten CORS

internal/middleware/cors.go

@@ -1,22 +1,55 @@
 package middleware
 
 import (
+	"net"
+	"net/http"
+	"net/url"
+	"strings"
+
 	"github.com/gin-gonic/gin"
 )
 
 func CORS() gin.HandlerFunc {
 	return func(c *gin.Context) {
-		c.Header("Access-Control-Allow-Origin", "*")
+		origin := strings.TrimSpace(c.GetHeader("Origin"))
+		if origin != "" {
+			if isLoopbackOrigin(origin) {
+				c.Header("Access-Control-Allow-Origin", origin)
+				c.Header("Vary", "Origin")
 				c.Header("Access-Control-Allow-Methods", "GET, POST, PUT, PATCH, DELETE, OPTIONS")
 				c.Header("Access-Control-Allow-Headers", "Origin, Content-Type, Accept, Authorization")
 				c.Header("Access-Control-Expose-Headers", "Content-Length, Content-Disposition")
 				c.Header("Access-Control-Max-Age", "86400")
+			} else if c.Request.Method == http.MethodOptions {
+				c.AbortWithStatus(http.StatusForbidden)
+				return
+			}
+		}
 
-		if c.Request.Method == "OPTIONS" {
+		if c.Request.Method == http.MethodOptions {
-			c.AbortWithStatus(204)
+			c.AbortWithStatus(http.StatusNoContent)
 			return
 		}
 
 		c.Next()
 	}
 }
+
+func isLoopbackOrigin(origin string) bool {
+	u, err := url.Parse(origin)
+	if err != nil {
+		return false
+	}
+	if u.Scheme != "http" && u.Scheme != "https" {
+		return false
+	}
+	host := strings.TrimSpace(u.Hostname())
+	if host == "" {
+		return false
+	}
+	if strings.EqualFold(host, "localhost") {
+		return true
+	}
+	ip := net.ParseIP(host)
+	return ip != nil && ip.IsLoopback()
+}

internal/repository/pricelist.go

@@ -3,10 +3,12 @@ package repository
 import (
 	"errors"
 	"fmt"
+	"sort"
 	"strconv"
 	"strings"
 	"time"
 
+	"git.mchus.pro/mchus/quoteforge/internal/lotmatch"
 	"git.mchus.pro/mchus/quoteforge/internal/models"
 	"gorm.io/gorm"
 )
@@ -243,9 +245,91 @@ func (r *PricelistRepository) GetItems(pricelistID uint, offset, limit int, sear
 		}
 	}
 
+	if err := r.enrichItemsWithStock(items); err != nil {
+		return nil, 0, fmt.Errorf("enriching pricelist items with stock: %w", err)
+	}
+
 	return items, total, nil
 }
 
+func (r *PricelistRepository) enrichItemsWithStock(items []models.PricelistItem) error {
+	if len(items) == 0 {
+		return nil
+	}
+
+	resolver, err := lotmatch.NewLotResolverFromDB(r.db)
+	if err != nil {
+		return err
+	}
+
+	type stockRow struct {
+		Partnumber string   `gorm:"column:partnumber"`
+		Qty        *float64 `gorm:"column:qty"`
+	}
+	rows := make([]stockRow, 0)
+	if err := r.db.Raw(`
+		SELECT s.partnumber, s.qty
+		FROM stock_log s
+		INNER JOIN (
+			SELECT partnumber, MAX(date) AS max_date
+			FROM stock_log
+			GROUP BY partnumber
+		) latest ON latest.partnumber = s.partnumber AND latest.max_date = s.date
+		WHERE s.qty IS NOT NULL
+	`).Scan(&rows).Error; err != nil {
+		return err
+	}
+
+	lotTotals := make(map[string]float64, len(items))
+	lotPartnumbers := make(map[string][]string, len(items))
+	seenPartnumbers := make(map[string]map[string]struct{}, len(items))
+
+	for i := range rows {
+		row := rows[i]
+		if strings.TrimSpace(row.Partnumber) == "" {
+			continue
+		}
+		lotName, _, resolveErr := resolver.Resolve(row.Partnumber)
+		if resolveErr != nil || strings.TrimSpace(lotName) == "" {
+			continue
+		}
+
+		if row.Qty != nil {
+			lotTotals[lotName] += *row.Qty
+		}
+
+		pn := strings.TrimSpace(row.Partnumber)
+		if pn == "" {
+			continue
+		}
+		if _, ok := seenPartnumbers[lotName]; !ok {
+			seenPartnumbers[lotName] = make(map[string]struct{}, 4)
+		}
+		key := strings.ToLower(pn)
+		if _, exists := seenPartnumbers[lotName][key]; exists {
+			continue
+		}
+		seenPartnumbers[lotName][key] = struct{}{}
+		lotPartnumbers[lotName] = append(lotPartnumbers[lotName], pn)
+	}
+
+	for i := range items {
+		lotName := items[i].LotName
+		if qty, ok := lotTotals[lotName]; ok {
+			qtyCopy := qty
+			items[i].AvailableQty = &qtyCopy
+		}
+		if partnumbers := lotPartnumbers[lotName]; len(partnumbers) > 0 {
+			sort.Slice(partnumbers, func(a, b int) bool {
+				return strings.ToLower(partnumbers[a]) < strings.ToLower(partnumbers[b])
+			})
+			items[i].Partnumbers = partnumbers
+		}
+	}
+
+	return nil
+}
+
 // GetLotNames returns distinct lot names from pricelist items.
 func (r *PricelistRepository) GetLotNames(pricelistID uint) ([]string, error) {
 	var lotNames []string