mcp in cart

2026-06-17 21:43:38 +02:00
parent ad410d217c
commit 74dc252279
9 changed files with 1054 additions and 13 deletions
@@ -0,0 +1,130 @@
+package mcp
+
+import (
+	"bytes"
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"path/filepath"
+	"testing"
+
+	"git.k6n.net/mats/go-cart-actor/pkg/promotions"
+)
+
+// call issues a tools/call against the handler and returns the decoded text
+// payload (the JSON the tool returned), failing on a tool/transport error.
+func call(t *testing.T, h http.Handler, name string, args map[string]any) map[string]any {
+	t.Helper()
+	body, _ := json.Marshal(map[string]any{
+		"jsonrpc": "2.0",
+		"id":      1,
+		"method":  "tools/call",
+		"params":  map[string]any{"name": name, "arguments": args},
+	})
+	rec := httptest.NewRecorder()
+	req := httptest.NewRequest(http.MethodPost, "/mcp", bytes.NewReader(body))
+	h.ServeHTTP(rec, req)
+	if rec.Code != http.StatusOK {
+		t.Fatalf("%s: status %d", name, rec.Code)
+	}
+	var resp struct {
+		Result struct {
+			IsError bool `json:"isError"`
+			Content []struct {
+				Text string `json:"text"`
+			} `json:"content"`
+		} `json:"result"`
+		Error *struct {
+			Message string `json:"message"`
+		} `json:"error"`
+	}
+	if err := json.Unmarshal(rec.Body.Bytes(), &resp); err != nil {
+		t.Fatalf("%s: decode response: %v (%s)", name, err, rec.Body.String())
+	}
+	if resp.Error != nil {
+		t.Fatalf("%s: rpc error: %s", name, resp.Error.Message)
+	}
+	if resp.Result.IsError {
+		t.Fatalf("%s: tool error: %s", name, resp.Result.Content[0].Text)
+	}
+	var out map[string]any
+	if len(resp.Result.Content) > 0 {
+		_ = json.Unmarshal([]byte(resp.Result.Content[0].Text), &out)
+	}
+	return out
+}
+
+func TestPromotionMCPRoundTrip(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "promotions.json")
+	store, err := promotions.NewStore(path)
+	if err != nil {
+		t.Fatal(err)
+	}
+	h := New(store, nil).Handler()
+
+	rule := map[string]any{
+		"id":       "volymrabatt",
+		"name":     "Volymrabatt",
+		"status":   "active",
+		"priority": 100,
+		"conditions": []any{
+			map[string]any{"id": "min", "type": "cart_total", "operator": ">=", "value": 2000000},
+		},
+		"actions": []any{
+			map[string]any{
+				"id": "tiers", "type": "tiered_discount", "value": 0,
+				"config": map[string]any{
+					"tiers": []any{
+						map[string]any{"minTotal": 2000000, "maxTotal": 4000000, "percent": 5},
+						map[string]any{"minTotal": 4000000, "maxTotal": 6000000, "percent": 9},
+						map[string]any{"minTotal": 6000000, "maxTotal": 9000000, "percent": 14},
+					},
+				},
+			},
+		},
+	}
+
+	// Upsert (create).
+	got := call(t, h, "upsert_promotion", map[string]any{"promotion": rule})
+	if got["replaced"] != false {
+		t.Errorf("first upsert should create, got replaced=%v", got["replaced"])
+	}
+
+	// It persisted to disk and a fresh store sees it.
+	reloaded, err := promotions.NewStore(path)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(reloaded.List()) != 1 {
+		t.Fatalf("expected 1 persisted promotion, got %d", len(reloaded.List()))
+	}
+
+	// List.
+	listed := call(t, h, "list_promotions", map[string]any{"status": "active"})
+	if c, _ := listed["count"].(float64); c != 1 {
+		t.Errorf("list count = %v, want 1", listed["count"])
+	}
+
+	// Preview the 9% mid tier at 50 000 kr.
+	preview := call(t, h, "preview_cart_discount", map[string]any{"cartTotalIncVat": 5000000})
+	if d, _ := preview["discountIncVat"].(float64); int64(d) != 450000 {
+		t.Errorf("discount = %v, want 450000", preview["discountIncVat"])
+	}
+	if n, _ := preview["netIncVat"].(float64); int64(n) != 4550000 {
+		t.Errorf("net = %v, want 4550000", preview["netIncVat"])
+	}
+
+	// Toggle off → preview yields no discount.
+	call(t, h, "set_promotion_status", map[string]any{"id": "volymrabatt", "status": "inactive"})
+	off := call(t, h, "preview_cart_discount", map[string]any{"cartTotalIncVat": 5000000})
+	if d, _ := off["discountIncVat"].(float64); d != 0 {
+		t.Errorf("inactive promo should give 0 discount, got %v", off["discountIncVat"])
+	}
+
+	// Delete.
+	call(t, h, "delete_promotion", map[string]any{"id": "volymrabatt"})
+	final := call(t, h, "list_promotions", nil)
+	if c, _ := final["count"].(float64); c != 0 {
+		t.Errorf("after delete count = %v, want 0", final["count"])
+	}
+}