package wallet

import (
	"context"
	"testing"

	"hfb_sys/backend/internal/model"

	"gorm.io/driver/sqlite"
	"gorm.io/gorm"
	"gorm.io/gorm/logger"
)

// setupTestDB 创建测试数据库连接（使用内存 SQLite）
func setupTestDB(t *testing.T) *gorm.DB {
	db, err := gorm.Open(sqlite.Open(":memory:"), &gorm.Config{
		Logger: logger.Default.LogMode(logger.Silent),
	})
	if err != nil {
		t.Fatalf("无法创建测试数据库连接: %v", err)
	}

	// 迁移必要的表
	if err := db.AutoMigrate(
		&model.WalletAccount{},
		&model.WalletLedger{},
	); err != nil {
		t.Fatalf("数据库迁移失败: %v", err)
	}

	return db
}

// cleanupTestDB 清理测试数据（内存数据库无需清理）
func cleanupTestDB(t *testing.T, db *gorm.DB) {
	// 内存数据库，测试结束后自动清理
}

// TestRepositoryAccountCreatesAccountIfNotExists 测试账户自动创建
func TestRepositoryAccountCreatesAccountIfNotExists(t *testing.T) {
	db := setupTestDB(t)
	defer cleanupTestDB(t, db)

	repo := NewRepository(db)
	ctx := context.Background()
	userID := uint64(1001)

	account, err := repo.Account(ctx, userID)
	if err != nil {
		t.Fatalf("Account() error = %v", err)
	}

	if account.UserID != userID {
		t.Fatalf("UserID = %d, want %d", account.UserID, userID)
	}
	if account.AvailableBalanceCent != 0 {
		t.Fatalf("AvailableBalanceCent = %d, want 0", account.AvailableBalanceCent)
	}
	if account.FrozenBalanceCent != 0 {
		t.Fatalf("FrozenBalanceCent = %d, want 0", account.FrozenBalanceCent)
	}
	if account.Status != "active" {
		t.Fatalf("Status = %s, want active", account.Status)
	}
}

// TestAppendEntriesUpdatesBalanceCorrectly 测试 AppendEntries 余额计算
func TestAppendEntriesUpdatesBalanceCorrectly(t *testing.T) {
	db := setupTestDB(t)
	defer cleanupTestDB(t, db)

	userID := uint64(1005)

	testCases := []struct {
		name          string
		entries       []Entry
		wantAvailable int64
		wantFrozen    int64
	}{
		{
			name: "可用余额入账",
			entries: []Entry{
				{UserID: userID, Direction: "in", AmountCent: 10000, BalanceType: "available", BizType: "test", BizNo: "T1"},
			},
			wantAvailable: 10000,
			wantFrozen:    0,
		},
		{
			name: "冻结余额入账",
			entries: []Entry{
				{UserID: userID, Direction: "in", AmountCent: 5000, BalanceType: "frozen", BizType: "test", BizNo: "T2"},
			},
			wantAvailable: 10000,
			wantFrozen:    5000,
		},
		{
			name: "可用余额出账",
			entries: []Entry{
				{UserID: userID, Direction: "out", AmountCent: 3000, BalanceType: "available", BizType: "test", BizNo: "T3"},
			},
			wantAvailable: 7000,
			wantFrozen:    5000,
		},
		{
			name: "冻结余额出账",
			entries: []Entry{
				{UserID: userID, Direction: "out", AmountCent: 2000, BalanceType: "frozen", BizType: "test", BizNo: "T4"},
			},
			wantAvailable: 7000,
			wantFrozen:    3000,
		},
	}

	for _, tc := range testCases {
		t.Run(tc.name, func(t *testing.T) {
			err := db.Transaction(func(tx *gorm.DB) error {
				return AppendEntries(tx, tc.entries...)
			})
			if err != nil {
				t.Fatalf("AppendEntries() error = %v", err)
			}

			var account model.WalletAccount
			db.Where("user_id = ?", userID).First(&account)

			if account.AvailableBalanceCent != tc.wantAvailable {
				t.Fatalf("AvailableBalanceCent = %d, want %d", account.AvailableBalanceCent, tc.wantAvailable)
			}
			if account.FrozenBalanceCent != tc.wantFrozen {
				t.Fatalf("FrozenBalanceCent = %d, want %d", account.FrozenBalanceCent, tc.wantFrozen)
			}
		})
	}
}

// TestAppendEntriesRejectsInsufficientBalance 测试余额不足时拒绝扣款
func TestAppendEntriesRejectsInsufficientBalance(t *testing.T) {
	db := setupTestDB(t)
	defer cleanupTestDB(t, db)

	userID := uint64(1006)

	// 先入账 1000
	db.Transaction(func(tx *gorm.DB) error {
		return AppendEntries(tx, Entry{
			UserID:      userID,
			Direction:   "in",
			AmountCent:  1000,
			BalanceType: "available",
			BizType:     "test",
			BizNo:       "INIT",
		})
	})

	// 尝试扣款 2000（余额不足）
	err := db.Transaction(func(tx *gorm.DB) error {
		return AppendEntries(tx, Entry{
			UserID:      userID,
			Direction:   "out",
			AmountCent:  2000,
			BalanceType: "available",
			BizType:     "test",
			BizNo:       "FAIL",
		})
	})

	if err != ErrInsufficientBalance {
		t.Fatalf("error = %v, want ErrInsufficientBalance", err)
	}

	// 验证余额未变化
	var account model.WalletAccount
	db.Where("user_id = ?", userID).First(&account)
	if account.AvailableBalanceCent != 1000 {
		t.Fatalf("余额 = %d, want 1000（回滚后应保持不变）", account.AvailableBalanceCent)
	}
}

// TestAppendEntriesSkipsZeroAmount 测试跳过零金额条目
func TestAppendEntriesSkipsZeroAmount(t *testing.T) {
	db := setupTestDB(t)
	defer cleanupTestDB(t, db)

	userID := uint64(1007)

	err := db.Transaction(func(tx *gorm.DB) error {
		return AppendEntries(tx,
			Entry{UserID: userID, Direction: "in", AmountCent: 0, BalanceType: "available", BizType: "test", BizNo: "ZERO"},
			Entry{UserID: userID, Direction: "in", AmountCent: 1000, BalanceType: "available", BizType: "test", BizNo: "VALID"},
		)
	})

	if err != nil {
		t.Fatalf("AppendEntries() error = %v", err)
	}

	// 验证只有 1 条账本记录（零金额被跳过）
	var count int64
	db.Model(&model.WalletLedger{}).Where("user_id = ?", userID).Count(&count)
	if count != 1 {
		t.Fatalf("账本记录数 = %d, want 1（零金额应被跳过）", count)
	}
}

// TestRepositoryLedgerPagination 测试账本分页
func TestRepositoryLedgerPagination(t *testing.T) {
	db := setupTestDB(t)
	defer cleanupTestDB(t, db)

	repo := NewRepository(db)
	ctx := context.Background()
	userID := uint64(1008)

	// 创建 25 条记录
	entries := make([]Entry, 25)
	for i := 0; i < 25; i++ {
		entries[i] = Entry{
			UserID:      userID,
			Direction:   "in",
			AmountCent:  100,
			BalanceType: "available",
			BizType:     "test",
			BizNo:       "PAGE" + string(rune(i)),
		}
	}
	db.Transaction(func(tx *gorm.DB) error {
		return AppendEntries(tx, entries...)
	})

	// 测试第一页
	page1, err := repo.Ledger(ctx, userID, 1, 10)
	if err != nil {
		t.Fatalf("Ledger() page 1 error = %v", err)
	}
	if page1.Total != 25 {
		t.Fatalf("Total = %d, want 25", page1.Total)
	}

	// 断言 Items 类型并检查长度
	items1, ok := page1.Items.([]LedgerDTO)
	if !ok {
		t.Fatalf("Items type = %T, want []LedgerDTO", page1.Items)
	}
	if len(items1) != 10 {
		t.Fatalf("Page 1 items = %d, want 10", len(items1))
	}

	// 测试第三页
	page3, err := repo.Ledger(ctx, userID, 3, 10)
	if err != nil {
		t.Fatalf("Ledger() page 3 error = %v", err)
	}

	items3, ok := page3.Items.([]LedgerDTO)
	if !ok {
		t.Fatalf("Items type = %T, want []LedgerDTO", page3.Items)
	}
	if len(items3) != 5 {
		t.Fatalf("Page 3 items = %d, want 5", len(items3))
	}
}
