PHP多活动事件中参数差异化处理的上下文对象设计模式

class FirstCampaign {
    public function onFirstPurchase($arg1, $arg2, User $user) {
        // ...
    }
    public function onFirstTrade($price, $something, User $user, Model $model) {
        // ...
    }
}

class SecondCampaign {
    public function onFirstPurchase(User $user) {
        // ...
    }
    public function onFirstTrade(Model $model) {
        // ...
    }
}

class ThirdCampaign {
    public function onFirstPurchase(User $user, Model $model, int $abc) {
        // ...
    }
    public function onFirstTrade() {
        // ...
    }
}

<?php

interface CampaignInterface {
    public function onFirstPurchase(User $user, PurchaseContextInterface $context);
    public function onFirstTrade(TradeContextInterface $context);
}

<?php

// 用户类，假设已存在
class User {}
// 模型类，假设已存在
class Model {}

interface PurchaseContextInterface {
    // 可以定义通用方法，或保持为空作为标记接口
}

interface TradeContextInterface {
    // 可以定义通用方法，或保持为空作为标记接口
}

<?php

// 具体的活动类实现
class FirstCampaign implements CampaignInterface {
    public function onFirstPurchase(User $user, PurchaseContextInterface $context) {
        // 确保传入的是FirstCampaignPurchaseContext
        if ($context instanceof FirstCampaignPurchaseContext) {
            echo "FirstCampaign: onFirstPurchase for User ID: " . $user->getId() . "\n";
            echo "Arg1: " . $context->getArg1() . ", Arg2: " . $context->getArg2() . "\n";
        } else {
            throw new InvalidArgumentException("Invalid context for FirstCampaign::onFirstPurchase");
        }
        // ... 具体的业务逻辑
    }

    public function onFirstTrade(TradeContextInterface $context) {
        if ($context instanceof FirstCampaignTradeContext) {
            echo "FirstCampaign: onFirstTrade\n";
            echo "Price: " . $context->getPrice() . ", Something: " . $context->getSomething() . "\n";
            // ... 具体的业务逻辑
        } else {
            throw new InvalidArgumentException("Invalid context for FirstCampaign::onFirstTrade");
        }
    }
}

<?php

// FirstCampaign 专属的购买事件上下文
class FirstCampaignPurchaseContext implements PurchaseContextInterface {
    private $arg1;
    private $arg2;

    public function __construct($arg1, $arg2) {
        $this->arg1 = $arg1;
        $this->arg2 = $arg2;
    }

    public function getArg1() {
        return $this->arg1;
    }

    public function getArg2() {
        return $this->arg2;
    }
}

// FirstCampaign 专属的交易事件上下文
class FirstCampaignTradeContext implements TradeContextInterface {
    private $price;
    private $something;
    private $model; // 假设Model是通用类型

    public function __construct($price, $something, Model $model) {
        $this->price = $price;
        $this->something = $something;
        $this->model = $model;
    }

    public function getPrice() {
        return $this->price;
    }

    public function getSomething() {
        return $this->something;
    }

    public function getModel(): Model {
        return $this->model;
    }
}

// 示例：SecondCampaign 的上下文
class SecondCampaignPurchaseContext implements PurchaseContextInterface {
    // SecondCampaign::onFirstPurchase 只需要User，所以这个上下文可以为空或者只包含特定于SecondCampaign的额外信息
    public function __construct() {}
}

class SecondCampaignTradeContext implements TradeContextInterface {
    private $model;

    public function __construct(Model $model) {
        $this->model = $model;
    }

    public function getModel(): Model {
        return $this->model;
    }
}

<?php

// 假设我们有一个用户对象和一个模型对象
$currentUser = new User();
$currentModel = new Model();

// 实例化 FirstCampaign
$firstCampaign = new FirstCampaign();

// 触发 FirstCampaign 的 onFirstPurchase 事件
$purchaseContextForFirstCampaign = new FirstCampaignPurchaseContext('valueA', 'valueB');
$firstCampaign->onFirstPurchase($currentUser, $purchaseContextForFirstCampaign);

// 触发 FirstCampaign 的 onFirstTrade 事件
$tradeContextForFirstCampaign = new FirstCampaignTradeContext(100.50, 'product_id_xyz', $currentModel);
$firstCampaign->onFirstTrade($tradeContextForFirstCampaign);

// 实例化 SecondCampaign
$secondCampaign = new SecondCampaign();

// 触发 SecondCampaign 的 onFirstPurchase 事件
$purchaseContextForSecondCampaign = new SecondCampaignPurchaseContext(); // 此时上下文可能为空或包含少量信息
$secondCampaign->onFirstPurchase($currentUser, $purchaseContextForSecondCampaign);

// 触发 SecondCampaign 的 onFirstTrade 事件
$tradeContextForSecondCampaign = new SecondCampaignTradeContext($currentModel);
$secondCampaign->onFirstTrade($tradeContextForSecondCampaign);