外卖配送开发系统的订单状态流转与结算逻辑详解

1. CREATED           已创建（待支付）
2. PAID              已支付（待接单）
3. ACCEPTED          商户已接单
4. PREPARING         制作中
5. WAITING_DELIVERY  待骑手接单
6. DELIVERING        配送中
7. COMPLETED         已完成
8. CANCELLED         已取消
9. REFUNDING         退款中
10. REFUNDED         已退款

CREATE TABLE orders (
    id BIGINT PRIMARY KEY AUTO_INCREMENT,
    user_id BIGINT NOT NULL,
    merchant_id BIGINT NOT NULL,
    rider_id BIGINT,
    total_amount DECIMAL(10,2),
    pay_amount DECIMAL(10,2),
    status VARCHAR(32),
    created_at DATETIME,
    updated_at DATETIME,
    version INT DEFAULT 0
);

CREATE TABLE order_status_logs (
    id BIGINT PRIMARY KEY AUTO_INCREMENT,
    order_id BIGINT,
    from_status VARCHAR(32),
    to_status VARCHAR(32),
    operator_type VARCHAR(32),
    created_at DATETIME
);

public enum OrderStatus {
    CREATED,
    PAID,
    ACCEPTED,
    PREPARING,
    WAITING_DELIVERY,
    DELIVERING,
    COMPLETED,
    CANCELLED,
    REFUNDING,
    REFUNDED
}

@Transactional
public void changeStatus(Long orderId, OrderStatus newStatus) {

    Order order = orderRepository.findById(orderId);

    OrderStatus oldStatus = order.getStatus();

    if (!canTransfer(oldStatus, newStatus)) {
        throw new RuntimeException("非法状态流转");
    }

    order.setStatus(newStatus);
    order.setVersion(order.getVersion() + 1);

    orderRepository.update(order);

    orderStatusLogRepository.save(
        new OrderStatusLog(orderId, oldStatus, newStatus)
    );
}

private boolean canTransfer(OrderStatus from, OrderStatus to) {

    Map<OrderStatus, List<OrderStatus>> flowMap = new HashMap<>();

    flowMap.put(OrderStatus.CREATED, Arrays.asList(OrderStatus.PAID, OrderStatus.CANCELLED));
    flowMap.put(OrderStatus.PAID, Arrays.asList(OrderStatus.ACCEPTED, OrderStatus.CANCELLED));
    flowMap.put(OrderStatus.ACCEPTED, Arrays.asList(OrderStatus.PREPARING));
    flowMap.put(OrderStatus.PREPARING, Arrays.asList(OrderStatus.WAITING_DELIVERY));
    flowMap.put(OrderStatus.WAITING_DELIVERY, Arrays.asList(OrderStatus.DELIVERING));
    flowMap.put(OrderStatus.DELIVERING, Arrays.asList(OrderStatus.COMPLETED));
    
    return flowMap.getOrDefault(from, Collections.emptyList()).contains(to);
}

用户支付金额 = 商品金额 + 配送费
平台抽佣 = 商品金额 × 抽佣比例
骑手收入 = 配送费
商户收入 = 商品金额 - 平台抽佣

CREATE TABLE order_settlement (
    id BIGINT PRIMARY KEY AUTO_INCREMENT,
    order_id BIGINT,
    merchant_income DECIMAL(10,2),
    rider_income DECIMAL(10,2),
    platform_income DECIMAL(10,2),
    settlement_status VARCHAR(32),
    created_at DATETIME
);

@EventListener
public void handleOrderCompleted(OrderCompletedEvent event) {
    settle(event.getOrderId());
}

@Transactional
public void settle(Long orderId) {

    Order order = orderRepository.findById(orderId);

    BigDecimal commissionRate = new BigDecimal("0.15");

    BigDecimal platformIncome = 
        order.getTotalAmount().multiply(commissionRate);

    BigDecimal merchantIncome = 
        order.getTotalAmount().subtract(platformIncome);

    BigDecimal riderIncome = 
        order.getDeliveryFee();

    OrderSettlement settlement = new OrderSettlement();
    settlement.setOrderId(orderId);
    settlement.setMerchantIncome(merchantIncome);
    settlement.setPlatformIncome(platformIncome);
    settlement.setRiderIncome(riderIncome);
    settlement.setSettlementStatus("PENDING");

    settlementRepository.save(settlement);
}

UNIQUE KEY uk_order_id (order_id)