package channel

import (
	"context"
	"errors"
	"fmt"
	"sync"
)

// MockChannel 联调用模拟渠道：订单创建即返回二维码内容，
// 通过 MarkMockPaid 模拟"车主已付款"，QueryOrder 才会返回已支付。
type MockChannel struct {
	mu   sync.Mutex
	paid map[string]string // orderNo -> mock transaction id
}

func NewMockChannel() *MockChannel {
	return &MockChannel{paid: map[string]string{}}
}

func (m *MockChannel) Code() string { return ChannelMock }

func (m *MockChannel) CreateOrder(ctx context.Context, req CreateOrderRequest) (CreateOrderResult, error) {
	// 二维码内容对 mock 无真实意义，保证同一订单稳定即可。
	return CreateOrderResult{CodeURL: fmt.Sprintf("mockpay:order:%s:%.2f", req.OrderNo, req.Amount)}, nil
}

func (m *MockChannel) QueryOrder(ctx context.Context, orderNo string) (QueryOrderResult, error) {
	m.mu.Lock()
	defer m.mu.Unlock()
	if txn, ok := m.paid[orderNo]; ok {
		return QueryOrderResult{Status: QueryPaid, TransactionID: txn}, nil
	}
	return QueryOrderResult{Status: QueryPending}, nil
}

// MarkMockPaid 模拟渠道侧支付成功（调试端点调用）。
func (m *MockChannel) MarkMockPaid(orderNo string) {
	m.mu.Lock()
	defer m.mu.Unlock()
	m.paid[orderNo] = "MOCK" + orderNo
}

// MarkMockPaid 从注册表取 mock 渠道并模拟支付成功。
func MarkMockPaid(orderNo string) error {
	ch, err := Get(ChannelMock)
	if err != nil {
		return err
	}
	mock, ok := ch.(*MockChannel)
	if !ok {
		return errors.New("mock 渠道不可用")
	}
	mock.MarkMockPaid(orderNo)
	return nil
}