package feeds

import (
	"encoding/json"
	"testing"

	"github.com/google/uuid"
)

func TestDetectMappedChangesPriceStock(t *testing.T) {
	t.Parallel()
	old := []byte(`{"price":"10","stock":"5","title":"A"}`)
	changes := detectMappedChanges(old, map[string]any{"price": "12", "stock": "5", "title": "A"})
	if len(changes) != 1 || changes[0] != "price" {
		t.Fatalf("changes=%v", changes)
	}
	changes = detectMappedChanges(old, map[string]any{"price": "10", "stock": "0", "title": "A"})
	if len(changes) != 1 || changes[0] != "stock" {
		t.Fatalf("stock changes=%v", changes)
	}
	changes = detectMappedChanges(old, map[string]any{"price": "11", "stock": "1", "title": "B", "availability": "out"})
	want := map[string]bool{"price": true, "stock": true, "title": true, "availability": true}
	for _, c := range changes {
		if !want[c] {
			t.Fatalf("unexpected %s in %v", c, changes)
		}
		delete(want, c)
	}
	if len(want) != 0 {
		t.Fatalf("missing %v from %v", want, changes)
	}
}

func TestClassifyUpsertOpsStampsSyncChanges(t *testing.T) {
	t.Parallel()
	idUpdate := uuid.MustParse("22222222-2222-2222-2222-222222222222")
	existing := map[string]existingProduct{
		"update": {ID: idUpdate, MappedData: []byte(`{"price":"10","title":"Old"}`)},
	}
	chunk := []pendingProduct{
		{GTIN: "new", RawData: map[string]string{"EAN": "new"}, MappedData: map[string]any{"title": "N"}},
		{GTIN: "update", RawData: map[string]string{"EAN": "update"}, MappedData: map[string]any{"price": "12", "title": "Old"}},
	}
	ops, skipped := classifyUpsertOps(chunk, existing)
	if skipped != 0 || len(ops) != 2 {
		t.Fatalf("ops=%d skipped=%d", len(ops), skipped)
	}
	if ops[0].kind != upsertOpInsert || len(ops[0].changes) != 1 || ops[0].changes[0] != "new" {
		t.Fatalf("insert op=%+v", ops[0])
	}
	var mapped map[string]any
	if err := json.Unmarshal(ops[0].mappedJSON, &mapped); err != nil {
		t.Fatal(err)
	}
	tags, _ := mapped[syncChangesMappedKey].([]any)
	if len(tags) != 1 || tags[0] != "new" {
		t.Fatalf("insert mapped meta=%v", mapped[syncChangesMappedKey])
	}
	if ops[1].kind != upsertOpUpdate || len(ops[1].changes) != 1 || ops[1].changes[0] != "price" {
		t.Fatalf("update op=%+v", ops[1])
	}
}

func TestSyncDeltaCountsAddChanges(t *testing.T) {
	t.Parallel()
	var d syncDeltaCounts
	d.addChanges([]string{"price", "stock"})
	d.addChanges([]string{"new"})
	d.addChanges(nil)
	if d.PriceChanged != 1 || d.StockChanged != 1 || d.New != 1 || d.OtherChanged != 1 {
		t.Fatalf("%+v", d)
	}
}

func TestPreserveSyncedExtrasKeepsCategory(t *testing.T) {
	t.Parallel()
	existing := []byte(`{"price":"10","category":"46","title":"Roborock"}`)
	mapped := map[string]any{"price": "12", "title": "Roborock"}
	got := preserveSyncedExtras(existing, mapped)
	if got["category"] != "46" {
		t.Fatalf("category=%v want 46", got["category"])
	}
	if got["price"] != "12" {
		t.Fatalf("price=%v want 12", got["price"])
	}
	// Explicit new category wins.
	mapped2 := map[string]any{"price": "12", "category": "120"}
	got2 := preserveSyncedExtras(existing, mapped2)
	if got2["category"] != "120" {
		t.Fatalf("category=%v want 120", got2["category"])
	}
	// Empty / none prior must not invent a category.
	got3 := preserveSyncedExtras([]byte(`{"category":"none"}`), map[string]any{"title": "X"})
	if _, ok := got3["category"]; ok {
		t.Fatalf("unexpected category=%v", got3["category"])
	}
}

func TestClassifyUpsertOpsPreservesCategory(t *testing.T) {
	t.Parallel()
	idUpdate := uuid.MustParse("33333333-3333-3333-3333-333333333333")
	existing := map[string]existingProduct{
		"keep": {ID: idUpdate, MappedData: []byte(`{"price":"10","category":"46","title":"Old"}`)},
	}
	chunk := []pendingProduct{
		{GTIN: "keep", RawData: map[string]string{"EAN": "keep"}, MappedData: map[string]any{"price": "12", "title": "Old"}},
	}
	ops, skipped := classifyUpsertOps(chunk, existing)
	if skipped != 0 || len(ops) != 1 {
		t.Fatalf("ops=%d skipped=%d", len(ops), skipped)
	}
	if ops[0].kind != upsertOpUpdate {
		t.Fatalf("kind=%v want update", ops[0].kind)
	}
	var mapped map[string]any
	if err := json.Unmarshal(ops[0].mappedJSON, &mapped); err != nil {
		t.Fatal(err)
	}
	if mapped["category"] != "46" {
		t.Fatalf("category wiped: %v", mapped["category"])
	}
	if mapped["price"] != "12" {
		t.Fatalf("price=%v", mapped["price"])
	}
}