package handler

import (
	"fmt"
	"net/http"
	"testing"
	"time"

	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"

	"github.com/wangjia/jiu/backend/internal/model"
	"github.com/wangjia/jiu/backend/testutil"
)

// 调货核心场景：0 价入库 → 审核 → 部分出库 → 确认进价（前向补偿）。
func TestConfirmCost_BackfillsCostAndAdjustsPayable(t *testing.T) {
	db := testutil.SetupTestDB()
	shop := testutil.CreateTestShop(db, "CC_MAIN")
	admin := testutil.CreateTestUser(db, shop.ID, "admin", "pass", "admin")
	wh := testutil.CreateTestWarehouse(db, shop.ID, "仓")
	prod := testutil.CreateTestProduct(db, shop.ID, "茅台")
	adminToken := getAuthToken(admin.ID, shop.ID, "admin")
	r := setupProtectedRouter(db)

	// 0 价入库 10 → 审核
	w := makeRequest(r, "POST", "/api/v1/stock-in/orders", adminToken, map[string]interface{}{
		"warehouse_id": wh.ID, "order_date": time.Now().Format(time.RFC3339),
		"items": []map[string]interface{}{{"product_id": prod.ID, "quantity": 10.0, "unit_price": 0.0}},
	})
	require.Equal(t, http.StatusCreated, w.Code)
	inID := extractID(w)
	makeRequest(r, "PUT", fmt.Sprintf("/api/v1/stock-in/orders/%d/submit", inID), adminToken, nil)
	makeRequest(r, "PUT", fmt.Sprintf("/api/v1/stock-in/orders/%d/approve", inID), adminToken, nil)

	var inItem model.StockInItem
	require.NoError(t, db.Where("order_id = ?", inID).First(&inItem).Error)
	pid := inItem.ProductID // 序列号模型：入库为该行新建独立 product

	// 库存批次成本待定（CostPrice 为 NULL）
	var inv model.Inventory
	require.NoError(t, db.Where("shop_id = ? AND stock_in_item_id = ?", shop.ID, inItem.ID).First(&inv).Error)
	assert.Nil(t, inv.UnitPrice, "0 价入库时库存成本应为待定(NULL)")

	// 出库 4（售价 80，成本暂为 0）→ 审核
	w = makeRequest(r, "POST", "/api/v1/stock-out/orders", adminToken, map[string]interface{}{
		"warehouse_id": wh.ID, "order_date": time.Now().Format(time.RFC3339),
		"items": []map[string]interface{}{{"product_id": pid, "quantity": 4.0, "unit_price": 0.0, "sale_price": 80.0}},
	})
	outID := extractID(w)
	makeRequest(r, "PUT", fmt.Sprintf("/api/v1/stock-out/orders/%d/submit", outID), adminToken, nil)
	makeRequest(r, "PUT", fmt.Sprintf("/api/v1/stock-out/orders/%d/approve", outID), adminToken, nil)

	// 确认进价 50
	w = makeRequest(r, "POST", fmt.Sprintf("/api/v1/stock-in/orders/%d/confirm-cost", inID), adminToken,
		map[string]interface{}{"items": []map[string]interface{}{{"item_id": inItem.ID, "unit_price": 50.0}}})
	require.Equal(t, http.StatusOK, w.Code)

	// 1. 入库明细成本回填
	db.First(&inItem, inItem.ID)
	assert.Equal(t, 50.0, inItem.CostPrice)
	assert.Equal(t, 500.0, inItem.CostAmount)

	// 2. 剩余库存批次成本回填（6 件）
	db.First(&inv, inv.ID)
	require.NotNil(t, inv.UnitPrice)
	assert.Equal(t, 50.0, *inv.UnitPrice)

	// 3. 已出库行成本快照回填，售价/应收不变
	var outItem model.StockOutItem
	require.NoError(t, db.Where("order_id = ?", outID).First(&outItem).Error)
	assert.Equal(t, 50.0, outItem.CostPrice, "已出库成本应回填")
	assert.Equal(t, 200.0, outItem.CostAmount, "成本小计 = 50×4")
	assert.Equal(t, 80.0, outItem.SalePrice, "售价不应被改动")

	var outOrder model.StockOutOrder
	db.First(&outOrder, outID)
	assert.Equal(t, 320.0, outOrder.SaleTotal, "应收按售价 4×80，确认进价不影响")

	// 4. 入库单总额按差额重算：0 → 500
	var inOrder model.StockInOrder
	db.First(&inOrder, inID)
	assert.Equal(t, 500.0, inOrder.CostTotal)

	// 5. 应付差额调整流水：+500（balance 是应收应付混合滚动总账：0 入 + 320 应收 + 500 = 820）
	var adj model.FinanceRecord
	require.NoError(t, db.Where("shop_id = ? AND type = 'payable' AND ref_type = 'stock_in_cost_adjust'", shop.ID).
		First(&adj).Error)
	assert.Equal(t, 500.0, adj.Amount)
	assert.Equal(t, 820.0, adj.Balance)

	// 6. product 参考进价同步（pid 是入库新建的独立 product）
	var p2 model.Product
	require.NoError(t, db.First(&p2, pid).Error)
	assert.Equal(t, 50.0, p2.PurchasePrice)
}

// 非管理员无权确认进价。
func TestConfirmCost_Forbidden(t *testing.T) {
	db := testutil.SetupTestDB()
	shop := testutil.CreateTestShop(db, "CC_FORBID")
	admin := testutil.CreateTestUser(db, shop.ID, "admin", "pass", "admin")
	op := testutil.CreateTestUser(db, shop.ID, "op", "pass", "operator")
	wh := testutil.CreateTestWarehouse(db, shop.ID, "仓")
	prod := testutil.CreateTestProduct(db, shop.ID, "五粮液")
	adminToken := getAuthToken(admin.ID, shop.ID, "admin")
	opToken := getAuthToken(op.ID, shop.ID, "operator")
	r := setupProtectedRouter(db)

	w := makeRequest(r, "POST", "/api/v1/stock-in/orders", adminToken, map[string]interface{}{
		"warehouse_id": wh.ID, "order_date": time.Now().Format(time.RFC3339),
		"items": []map[string]interface{}{{"product_id": prod.ID, "quantity": 5.0, "unit_price": 0.0}},
	})
	inID := extractID(w)
	makeRequest(r, "PUT", fmt.Sprintf("/api/v1/stock-in/orders/%d/submit", inID), adminToken, nil)
	makeRequest(r, "PUT", fmt.Sprintf("/api/v1/stock-in/orders/%d/approve", inID), adminToken, nil)
	var inItem model.StockInItem
	db.Where("order_id = ?", inID).First(&inItem)

	w = makeRequest(r, "POST", fmt.Sprintf("/api/v1/stock-in/orders/%d/confirm-cost", inID), opToken,
		map[string]interface{}{"items": []map[string]interface{}{{"item_id": inItem.ID, "unit_price": 30.0}}})
	assert.Equal(t, http.StatusForbidden, w.Code)
}

// 仅 approved 单可确认；草稿/待审核拒绝。
func TestConfirmCost_RejectsNonApproved(t *testing.T) {
	db := testutil.SetupTestDB()
	shop := testutil.CreateTestShop(db, "CC_DRAFT")
	admin := testutil.CreateTestUser(db, shop.ID, "admin", "pass", "admin")
	wh := testutil.CreateTestWarehouse(db, shop.ID, "仓")
	prod := testutil.CreateTestProduct(db, shop.ID, "汾酒")
	adminToken := getAuthToken(admin.ID, shop.ID, "admin")
	r := setupProtectedRouter(db)

	w := makeRequest(r, "POST", "/api/v1/stock-in/orders", adminToken, map[string]interface{}{
		"warehouse_id": wh.ID, "order_date": time.Now().Format(time.RFC3339),
		"items": []map[string]interface{}{{"product_id": prod.ID, "quantity": 5.0, "unit_price": 0.0}},
	})
	inID := extractID(w)
	var inItem model.StockInItem
	db.Where("order_id = ?", inID).First(&inItem)

	// 仍是 draft → 400
	w = makeRequest(r, "POST", fmt.Sprintf("/api/v1/stock-in/orders/%d/confirm-cost", inID), adminToken,
		map[string]interface{}{"items": []map[string]interface{}{{"item_id": inItem.ID, "unit_price": 30.0}}})
	assert.Equal(t, http.StatusBadRequest, w.Code)
}

// 重复确认：按新旧差额增量补偿，不重复全量。
func TestConfirmCost_RepeatableByDiff(t *testing.T) {
	db := testutil.SetupTestDB()
	shop := testutil.CreateTestShop(db, "CC_REPEAT")
	admin := testutil.CreateTestUser(db, shop.ID, "admin", "pass", "admin")
	wh := testutil.CreateTestWarehouse(db, shop.ID, "仓")
	prod := testutil.CreateTestProduct(db, shop.ID, "剑南春")
	adminToken := getAuthToken(admin.ID, shop.ID, "admin")
	r := setupProtectedRouter(db)

	w := makeRequest(r, "POST", "/api/v1/stock-in/orders", adminToken, map[string]interface{}{
		"warehouse_id": wh.ID, "order_date": time.Now().Format(time.RFC3339),
		"items": []map[string]interface{}{{"product_id": prod.ID, "quantity": 10.0, "unit_price": 0.0}},
	})
	inID := extractID(w)
	makeRequest(r, "PUT", fmt.Sprintf("/api/v1/stock-in/orders/%d/submit", inID), adminToken, nil)
	makeRequest(r, "PUT", fmt.Sprintf("/api/v1/stock-in/orders/%d/approve", inID), adminToken, nil)
	var inItem model.StockInItem
	db.Where("order_id = ?", inID).First(&inItem)

	// 第一次确认 50（diff 500）
	makeRequest(r, "POST", fmt.Sprintf("/api/v1/stock-in/orders/%d/confirm-cost", inID), adminToken,
		map[string]interface{}{"items": []map[string]interface{}{{"item_id": inItem.ID, "unit_price": 50.0}}})
	// 第二次修正为 60（diff 100）
	w = makeRequest(r, "POST", fmt.Sprintf("/api/v1/stock-in/orders/%d/confirm-cost", inID), adminToken,
		map[string]interface{}{"items": []map[string]interface{}{{"item_id": inItem.ID, "unit_price": 60.0}}})
	require.Equal(t, http.StatusOK, w.Code)

	db.First(&inItem, inItem.ID)
	assert.Equal(t, 60.0, inItem.CostPrice)

	var inOrder model.StockInOrder
	db.First(&inOrder, inID)
	assert.Equal(t, 600.0, inOrder.CostTotal, "总额 = 60×10")

	// 两条调整流水：+500 与 +100，余额滚动到 600
	var adjs []model.FinanceRecord
	db.Where("shop_id = ? AND ref_type = 'stock_in_cost_adjust'", shop.ID).Order("id ASC").Find(&adjs)
	require.Len(t, adjs, 2)
	assert.Equal(t, 500.0, adjs[0].Amount)
	assert.Equal(t, 100.0, adjs[1].Amount)
	assert.Equal(t, 600.0, adjs[1].Balance)
}