-- =====================================================
-- 1. 用户表 (Users)
-- 存储用户基本信息
-- 迷惑项：user_id、user_email、user_status 字段名相似
-- =====================================================

CREATE TABLE Users (
    user_id INT AUTO_INCREMENT PRIMARY KEY,
    username VARCHAR(50) NOT NULL UNIQUE,
    user_email VARCHAR(100) NOT NULL UNIQUE,
    password_hash VARCHAR(255) NOT NULL,
    full_name VARCHAR(100),
    phone VARCHAR(20),
    created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
    user_status TINYINT DEFAULT 1 COMMENT '1=活跃, 0=禁用',
    last_login DATETIME,
    INDEX idx_username (username),
    INDEX idx_user_email (user_email),
    INDEX idx_user_status (user_status)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

-- =====================================================
-- 2. 分类表 (Categories)
-- 存储产品分类信息
-- 迷惑项：自关联关系，category_id、category_name、parent_id
-- 特点：树形结构，支持多级分类
-- =====================================================

CREATE TABLE Categories (
    category_id INT AUTO_INCREMENT PRIMARY KEY,
    category_name VARCHAR(50) NOT NULL,
    category_desc VARCHAR(200),
    parent_id INT DEFAULT NULL,
    category_order INT DEFAULT 0,
    is_active TINYINT DEFAULT 1,
    created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
    updated_at DATETIME DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
    FOREIGN KEY (parent_id) REFERENCES Categories(category_id) ON DELETE SET NULL,
    INDEX idx_parent_id (parent_id),
    INDEX idx_category_name (category_name),
    INDEX idx_is_active (is_active)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

-- =====================================================
-- 3. 产品表 (Products)
-- 存储产品信息
-- 迷惑项：product_id、product_name、product_desc、product_status
-- 含义相近字段：price vs cost_price
-- =====================================================

CREATE TABLE Products (
    product_id INT AUTO_INCREMENT PRIMARY KEY,
    product_name VARCHAR(100) NOT NULL,
    product_desc TEXT,
    product_specs VARCHAR(255) COMMENT '产品规格JSON字符串',
    price DECIMAL(10,2) NOT NULL COMMENT '销售价格',
    cost_price DECIMAL(10,2) COMMENT '成本价格',
    stock_quantity INT DEFAULT 0,
    stock_alert_level INT DEFAULT 10,
    category_id INT,
    brand VARCHAR(50),
    product_status TINYINT DEFAULT 1 COMMENT '1=上架, 0=下架, 2=缺货',
    view_count INT DEFAULT 0,
    sales_count INT DEFAULT 0,
    created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
    updated_at DATETIME DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
    FOREIGN KEY (category_id) REFERENCES Categories(category_id) ON DELETE SET NULL,
    INDEX idx_product_name (product_name),
    INDEX idx_price (price),
    INDEX idx_category_id (category_id),
    INDEX idx_product_status (product_status),
    INDEX idx_brand (brand),
    INDEX idx_sales_count (sales_count)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

-- =====================================================
-- 4. 产品-分类关联表 (ProductCategories)
-- 实现产品和分类的多对多关系
-- 迷惑项：表名与Products、Categories相似
-- 特点：支持产品属于多个分类，设置主分类
-- =====================================================

CREATE TABLE ProductCategories (
    product_id INT NOT NULL,
    category_id INT NOT NULL,
    is_primary TINYINT DEFAULT 0 COMMENT '1=主分类, 0=副分类',
    added_at DATETIME DEFAULT CURRENT_TIMESTAMP,
    PRIMARY KEY (product_id, category_id),
    FOREIGN KEY (product_id) REFERENCES Products(product_id) ON DELETE CASCADE,
    FOREIGN KEY (category_id) REFERENCES Categories(category_id) ON DELETE CASCADE,
    INDEX idx_category_id (category_id),
    INDEX idx_is_primary (is_primary)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

-- =====================================================
-- 5. 订单表 (Orders)
-- 存储订单信息
-- 迷惑项：order_id、order_date、order_status
-- 含义相近字段：total_amount
-- =====================================================

CREATE TABLE Orders (
    order_id INT AUTO_INCREMENT PRIMARY KEY,
    order_number VARCHAR(30) NOT NULL UNIQUE COMMENT '订单编号',
    user_id INT NOT NULL,
    order_date DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
    total_amount DECIMAL(10,2) NOT NULL COMMENT '订单总金额',
    discount_amount DECIMAL(10,2) DEFAULT 0 COMMENT '折扣金额',
    shipping_fee DECIMAL(10,2) DEFAULT 0 COMMENT '运费',
    payment_method VARCHAR(30) COMMENT '支付方式',
    payment_status VARCHAR(20) DEFAULT 'pending' COMMENT 'pending/paid/failed/refunded',
    order_status VARCHAR(20) DEFAULT 'pending' COMMENT 'pending/confirmshipped/delivered/cancelled/completed',
    shipping_addr_id INT,
    billing_addr_id INT,
    shipping_addr VARCHAR(500) COMMENT '收货地址快照',
    billing_addr VARCHAR(500) COMMENT '账单地址快照',
    customer_remark VARCHAR(500),
    internal_remark VARCHAR(500),
    created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
    updated_at DATETIME DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
    FOREIGN KEY (user_id) REFERENCES Users(user_id) ON DELETE RESTRICT,
    INDEX idx_order_number (order_number),
    INDEX idx_user_id (user_id),
    INDEX idx_order_date (order_date),
    INDEX idx_order_status (order_status),
    INDEX idx_payment_status (payment_status)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

-- =====================================================
-- 6. 订单详情表 (OrderItems)
-- 存储订单中每个产品的详细信息
-- 迷惑项：order_item_id、order_id
-- 含义相近字段：item_price vs price，item_total vs total_amount
-- =====================================================

CREATE TABLE OrderItems (
    order_item_id INT AUTO_INCREMENT PRIMARY KEY,
    order_id INT NOT NULL,
    product_id INT NOT NULL,
    quantity INT NOT NULL,
    item_price DECIMAL(10,2) NOT NULL COMMENT '下单时的产品单价',
    item_cost DECIMAL(10,2) COMMENT '成本单价',
    item_discount DECIMAL(10,2) DEFAULT 0 COMMENT '该项折扣',
    item_total DECIMAL(10,2) NOT NULL COMMENT '该项总金额',
    item_status VARCHAR(20) DEFAULT 'pending' COMMENT 'pending/shipped/delivered/returned',
    created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
    updated_at DATETIME DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
    FOREIGN KEY (order_id) REFERENCES Orders(order_id) ON DELETE CASCADE,
    FOREIGN KEY (product_id) REFERENCES Products(product_id) ON DELETE RESTRICT,
    INDEX idx_order_id (order_id),
    INDEX idx_product_id (product_id),
    INDEX idx_item_status (item_status)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

-- =====================================================
-- 7. 地址表 (Addresses)
-- 存储用户的多个地址
-- 迷惑项：address_id、address_line1、address_line2
-- 一对多关系：一个用户有多个地址
-- =====================================================

CREATE TABLE Addresses (
    address_id INT AUTO_INCREMENT PRIMARY KEY,
    user_id INT NOT NULL,
    address_label VARCHAR(50) COMMENT '地址标签，如：家、公司',
    recipient_name VARCHAR(100) NOT NULL,
    recipient_phone VARCHAR(20) NOT NULL,
    country VARCHAR(50) DEFAULT '中国',
    province VARCHAR(50),
    city VARCHAR(50) NOT NULL,
    district VARCHAR(50),
    address_line1 VARCHAR(200) NOT NULL,
    address_line2 VARCHAR(200),
    postal_code VARCHAR(20),
    address_type VARCHAR(20) DEFAULT 'shipping' COMMENT 'shipping/billing/both',
    is_default TINYINT DEFAULT 0,
    is_active TINYINT DEFAULT 1,
    created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
    updated_at DATETIME DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
    FOREIGN KEY (user_id) REFERENCES Users(user_id) ON DELETE CASCADE,
    INDEX idx_user_id (user_id),
    INDEX idx_address_type (address_type),
    INDEX idx_is_default (is_default),
    INDEX idx_city (city)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

-- =====================================================
-- 8. 评论表 (Reviews)
-- 存储用户对产品的评论
-- 迷惑项：review_id、review_text、review_date
-- 多对一关系：评论关联用户和产品
-- =====================================================

CREATE TABLE Reviews (
    review_id INT AUTO_INCREMENT PRIMARY KEY,
    user_id INT NOT NULL,
    product_id INT NOT NULL,
    order_id INT COMMENT '订单ID，可选',
    rating TINYINT NOT NULL CHECK (rating >= 1 AND rating <= 5),
    review_title VARCHAR(100),
    review_text TEXT,
    is_anonymous TINYINT DEFAULT 0,
    is_verified TINYINT DEFAULT 0 COMMENT '是否购买后评论',
    helpful_count INT DEFAULT 0,
    reply_count INT DEFAULT 0,
    review_status VARCHAR(20) DEFAULT 'pending' COMMENT 'pending/approved/rejected',
    review_date DATETIME DEFAULT CURRENT_TIMESTAMP,
    created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
    updated_at DATETIME DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
    FOREIGN KEY (user_id) REFERENCES Users(user_id) ON DELETE CASCADE,
    FOREIGN KEY (product_id) REFERENCES Products(product_id) ON DELETE CASCADE,
    FOREIGN KEY (order_id) REFERENCES Orders(order_id) ON DELETE SET NULL,
    INDEX idx_user_id (user_id),
    INDEX idx_product_id (product_id),
    INDEX idx_rating (rating),
    INDEX idx_review_status (review_status),
    INDEX idx_review_date (review_date)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

-- =====================================================
-- 9. 购物车表 (CartItems)
-- 存储用户当前购物车中的商品
-- 迷惑项：cart_id、product_id、quantity
-- =====================================================

CREATE TABLE CartItems (
    cart_item_id INT AUTO_INCREMENT PRIMARY KEY,
    user_id INT NOT NULL,
    product_id INT NOT NULL,
    quantity INT NOT NULL DEFAULT 1,
    added_at DATETIME DEFAULT CURRENT_TIMESTAMP,
    updated_at DATETIME DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
    FOREIGN KEY (user_id) REFERENCES Users(user_id) ON DELETE CASCADE,
    FOREIGN KEY (product_id) REFERENCES Products(product_id) ON DELETE CASCADE,
    UNIQUE KEY uk_user_product (user_id, product_id),
    INDEX idx_user_id (user_id),
    INDEX idx_product_id (product_id)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

-- =====================================================
-- 10. 产品浏览历史表 (ProductViews)
-- 存储用户的浏览历史
-- 迷惑项：view_id、product_id、view_date
-- =====================================================

CREATE TABLE ProductViews (
    view_id BIGINT AUTO_INCREMENT PRIMARY KEY,
    user_id INT,
    product_id INT NOT NULL,
    view_date DATETIME DEFAULT CURRENT_TIMESTAMP,
    session_id VARCHAR(100),
    view_duration INT DEFAULT 0 COMMENT '浏览时长（秒）',
    source_type VARCHAR(30) COMMENT '来源：search/category/recommend/direct',
    FOREIGN KEY (user_id) REFERENCES Users(user_id) ON DELETE SET NULL,
    FOREIGN KEY (product_id) REFERENCES Products(product_id) ON DELETE CASCADE,
    INDEX idx_user_id (user_id),
    INDEX idx_product_id (product_id),
    INDEX idx_view_date (view_date)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

-- =====================================================
-- 11. 优惠券表 (Coupons)
-- 存储优惠券信息
-- 迷惑项：coupon_id、coupon_code、coupon_type
-- =====================================================

CREATE TABLE Coupons (
    coupon_id INT AUTO_INCREMENT PRIMARY KEY,
    coupon_code VARCHAR(30) NOT NULL UNIQUE,
    coupon_name VARCHAR(100) NOT NULL,
    coupon_desc VARCHAR(255),
    coupon_type VARCHAR(20) DEFAULT 'percentage' COMMENT 'percentage/fixed',
    discount_value DECIMAL(10,2) NOT NULL COMMENT '折扣值（百分比或固定金额）',
    min_order_amount DECIMAL(10,2) DEFAULT 0,
    max_discount_amount DECIMAL(10,2) COMMENT '最大折扣金额',
    usage_limit INT COMMENT '总使用次数限制',
    usage_limit_per_user INT DEFAULT 1,
    usage_count INT DEFAULT 0,
    valid_from DATETIME NOT NULL,
    valid_until DATETIME NOT NULL,
    is_active TINYINT DEFAULT 1,
    applicable_product_ids TEXT COMMENT '适用的产品ID列表，JSON格式',
    applicable_category_ids TEXT COMMENT '适用的分类ID列表，JSON格式',
    created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
    updated_at DATETIME DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
    INDEX idx_coupon_code (coupon_code),
    INDEX idx_valid_dates (valid_from, valid_until),
    INDEX idx_is_active (is_active)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

-- =====================================================
-- 12. 用户优惠券关联表 (UserCoupons)
-- 存储用户领取的优惠券
-- 迷惑项：user_coupon_id、user_id、coupon_id
-- =====================================================

CREATE TABLE UserCoupons (
    user_coupon_id INT AUTO_INCREMENT PRIMARY KEY,
    user_id INT NOT NULL,
    coupon_id INT NOT NULL,
    status VARCHAR(20) DEFAULT 'available' COMMENT 'available/used/expired',
    received_at DATETIME DEFAULT CURRENT_TIMESTAMP,
    used_at DATETIME,
    order_id INT,
    FOREIGN KEY (user_id) REFERENCES Users(user_id) ON DELETE CASCADE,
    FOREIGN KEY (coupon_id) REFERENCES Coupons(coupon_id) ON DELETE CASCADE,
    FOREIGN KEY (order_id) REFERENCES Orders(order_id) ON DELETE SET NULL,
    INDEX idx_user_id (user_id),
    INDEX idx_coupon_id (coupon_id),
    INDEX idx_status (status)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

-- =====================================================
-- 13. 产品收藏表 (Wishlists)
-- 存储用户收藏的产品
-- 迷惑项：wishlist_id、product_id、user_id
-- =====================================================

CREATE TABLE Wishlists (
    wishlist_id INT AUTO_INCREMENT PRIMARY KEY,
    user_id INT NOT NULL,
    product_id INT NOT NULL,
    added_at DATETIME DEFAULT CURRENT_TIMESTAMP,
    note VARCHAR(255),
    priority INT DEFAULT 0 COMMENT '优先级排序',
    FOREIGN KEY (user_id) REFERENCES Users(user_id) ON DELETE CASCADE,
    FOREIGN KEY (product_id) REFERENCES Products(product_id) ON DELETE CASCADE,
    UNIQUE KEY uk_user_product (user_id, product_id),
    INDEX idx_user_id (user_id),
    INDEX idx_product_id (product_id),
    INDEX idx_added_at (added_at)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

-- =====================================================
-- 14. 支付记录表 (Payments)
-- 存储订单支付信息
-- 迷惑项：payment_id、order_id、payment_amount
-- =====================================================

CREATE TABLE Payments (
    payment_id INT AUTO_INCREMENT PRIMARY KEY,
    order_id INT NOT NULL,
    payment_method VARCHAR(30) NOT NULL,
    payment_amount DECIMAL(10,2) NOT NULL,
    transaction_id VARCHAR(100) UNIQUE,
    payment_status VARCHAR(20) DEFAULT 'pending' COMMENT 'pending/success/failed/refunded',
    payment_date DATETIME,
    refund_amount DECIMAL(10,2) DEFAULT 0,
    refund_reason VARCHAR(255),
    gateway_response TEXT COMMENT '支付网关响应',
    created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
    updated_at DATETIME DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
    FOREIGN KEY (order_id) REFERENCES Orders(order_id) ON DELETE RESTRICT,
    INDEX idx_order_id (order_id),
    INDEX idx_transaction_id (transaction_id),
    INDEX idx_payment_status (payment_status),
    INDEX idx_payment_date (payment_date)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

-- =====================================================
-- 15. 管理员表 (Admins)
-- 存储管理员信息
-- 迷惑项：admin_id、admin_email、admin_role
-- =====================================================

CREATE TABLE Admins (
    admin_id INT AUTO_INCREMENT PRIMARY KEY,
    admin_email VARCHAR(100) NOT NULL UNIQUE,
    admin_name VARCHAR(50) NOT NULL,
    password_hash VARCHAR(255) NOT NULL,
    admin_role VARCHAR(30) DEFAULT 'staff' COMMENT 'super_admin/admin/staff',
    is_active TINYINT DEFAULT 1,
    last_login DATETIME,
    created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
    updated_at DATETIME DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
    INDEX idx_admin_email (admin_email),
    INDEX idx_admin_role (admin_role)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

-- =====================================================
-- 添加外键约束到Orders表的shipping_addr_id和billing_addr_id
-- =====================================================

ALTER TABLE Orders
ADD CONSTRAINT fk_orders_shipping_addr 
FOREIGN KEY (shipping_addr_id) REFERENCES Addresses(address_id) ON DELETE SET NULL;

ALTER TABLE Orders
ADD CONSTRAINT fk_orders_billing_addr 
FOREIGN KEY (billing_addr_id) REFERENCES Addresses(address_id) ON DELETE SET NULL;