package catalog

import (
	"encoding/json"
	"errors"
	"strings"
	"testing"
	"time"
)

// json.Number from a json.Decoder running with UseNumber() is the
// canonical path for precision-preserving producer parsing. Without this
// case, BuildFromMap would log+skip every projection that came through
// UseNumber — silently losing items.
func TestBuilderJSONNumber(t *testing.T) {
	// json.Number for SKU
	src := map[string]any{
		"sku":            json.Number("123456789012345"), // float64-unsafe
		"title":          "BigNumber SKU",
		"price_inc_vat":  json.Number("14995"), // already øre
		"currency":       "SEK",
		"tax_class":      "standard",
		"updated_at":     json.Number("1700000000000"),
	}
	p, err := Apply(DefaultSchema(), src)
	if err != nil {
		t.Fatalf("json.Number source rejected: %v", err)
	}
	if p.SKU != "123456789012345" {
		t.Errorf("SKU: got %q want %q", p.SKU, "123456789012345")
	}
	if p.PriceIncVat != 14995 {
		t.Errorf("PriceIncVat: got %d want %d", p.PriceIncVat, 14995)
	}
	if p.UpdatedAt != 1700000000000 {
		t.Errorf("UpdatedAt: got %d want %d", p.UpdatedAt, int64(1700000000000))
	}
}

func TestBuilderAttributes(t *testing.T) {
	s := DefaultSchema()
	s.AttributesFields = []string{"cart", "color"}
	src := map[string]any{
		"sku":           "X-1",
		"price_inc_vat": int64(100),
		"updated_at":    int64(1700000000000),
		"cart":          map[string]any{"data": "some-cart-data"},
		"color":         "red",
		"ignored":       "should-not-be-in-attrs",
	}
	p, err := Apply(s, src)
	if err != nil {
		t.Fatalf("Apply: %v", err)
	}
	var m map[string]any
	if err := json.Unmarshal(p.Attributes, &m); err != nil {
		t.Fatalf("unmarshal Attributes: %v", err)
	}
	if len(m) != 2 {
		t.Errorf("expected 2 attributes, got %d", len(m))
	}
	if cartVal, ok := m["cart"].(map[string]any); !ok || cartVal["data"] != "some-cart-data" {
		t.Errorf("cart attribute: got %v", m["cart"])
	}
	if m["color"] != "red" {
		t.Errorf("color attribute: got %v", m["color"])
	}
	if _, ok := m["ignored"]; ok {
		t.Errorf("ignored attribute was extracted: %v", m)
	}
}

// Updated=UseSourceField: missing source updated_at MUST be a loud error,
// not a stamp-now fallback. (Foot-gun 3 resolution: silence here invalidates
// every consumer's cache on rebuild.)
func TestBuilderRequiresUpdatedAt(t *testing.T) {
	src := map[string]any{
		"sku":           "X-1",
		"price_inc_vat": int64(100),
		// no "updated_at" key intentionally
	}
	_, err := Apply(DefaultSchema(), src)
	if err == nil {
		t.Fatal("UseSourceField + missing updated_at should error, not stamp-now")
	}
	if !errors.Is(err, ErrProjectionBuild) {
		t.Errorf("got %v want ErrProjectionBuild", err)
	}
	if !strings.Contains(err.Error(), "updated_at") {
		t.Errorf("error should mention updated_at: %v", err)
	}
}

// Same projection under StampAtPublish succeeds even without updated_at —
// that's the deliberate-fallback path. Used by sources with no other stamp.
// Bind the stamp to real wall-clock time (before ≤ actual ≤ after+slack)
// so the test distinguishes "stamp-now was called" from any other non-zero
// path.
func TestBuilderStampAtPublishFallback(t *testing.T) {
	s := DefaultSchema()
	s.UpdatedAtSource = StampAtPublish
	s.UpdatedAtField = "" // ignored when source is StampAtPublish
	before := time.Now().UnixMilli()
	src := map[string]any{
		"sku":           "X-2",
		"price_inc_vat": int64(100),
	}
	p, err := Apply(s, src)
	if err != nil {
		t.Fatalf("StampAtPublish should accept missing updated_at: %v", err)
	}
	after := time.Now().UnixMilli() + 1000 // generous slack for slow CI
	if p.UpdatedAt < before || p.UpdatedAt > after {
		t.Errorf("UpdatedAt should be stamp-now Unix-ms in [%d,%d], got %d", before, after, p.UpdatedAt)
	}
}

// Fractional float price with scale=1 must be loud-fail — the float arm of
// coercePrice has the same foot-gun 4 risk as the string arm (silent 100x
// bias if a tenant forgets PriceScale=100 and ships a float literal).
func TestBuilderFractionalFloatLowScaleRejected(t *testing.T) {
	src := map[string]any{
		"sku":           "F-1",
		"price_inc_vat": 99.95, // float major-units at scale=1
		"updated_at":    int64(1700000000000),
	}
	_, err := Apply(DefaultSchema(), src)
	if err == nil {
		t.Fatal("fractional float price at scale=1 should error, not silently produce 100 øre")
	}
	if !errors.Is(err, ErrProjectionBuild) {
		t.Errorf("got %v want ErrProjectionBuild", err)
	}
	if !strings.Contains(err.Error(), "PriceScale=100") {
		t.Errorf("error message should mention PriceScale=100 hint: %v", err)
	}
}

// json.Number("149.95") at scale=1 must reach the fractional guard via
// the json.Number branch — the precision-safe producer route.
func TestBuilderFractionalJSONNumberLowScaleRejected(t *testing.T) {
	src := map[string]any{
		"sku":           "JN-1",
		"price_inc_vat": json.Number("149.95"),
		"updated_at":    int64(1700000000000),
	}
	_, err := Apply(DefaultSchema(), src)
	if err == nil {
		t.Fatal("fractional json.Number at scale=1 should error, not silently produce 150 øre")
	}
	if !errors.Is(err, ErrProjectionBuild) {
		t.Errorf("got %v want ErrProjectionBuild", err)
	}
	if !strings.Contains(err.Error(), "PriceScale=100") {
		t.Errorf("error message should mention PriceScale=100 hint: %v", err)
	}
}

// Fractional string price with scale=1 must be loud-fail (a misconfigured
// tenant shipping major units without PriceScale=100 — silent 100x bias).
func TestBuilderFractionalStringPriceLowScaleRejected(t *testing.T) {
	src := map[string]any{
		"sku":           "X-1",
		"price_inc_vat": "149.95", // major units FRACTION at scale=1
		"updated_at":    int64(1700000000000),
	}
	_, err := Apply(DefaultSchema(), src)
	if err == nil {
		t.Fatal("fractional string at scale=1 should error, not silently produce 150 øre")
	}
	if !errors.Is(err, ErrProjectionBuild) {
		t.Errorf("got %v want ErrProjectionBuild", err)
	}
	if !strings.Contains(err.Error(), "PriceScale=100") {
		t.Errorf("error message should mention PriceScale=100 hint: %v", err)
	}
}

// Same string with scale=100 (correct major-unit config) succeeds.
func TestBuilderFractionalStringPriceCorrectScale(t *testing.T) {
	s := DefaultSchema()
	s.PriceScale = 100
	src := map[string]any{
		"sku":           "X-2",
		"price_inc_vat": "149.95",
		"updated_at":    int64(1700000000000),
	}
	p, err := Apply(s, src)
	if err != nil {
		t.Fatalf("scale=100 string price rejected: %v", err)
	}
	if p.PriceIncVat != 14995 {
		t.Errorf("PriceIncVat: got %d want %d", p.PriceIncVat, 14995)
	}
}