# -*- coding: utf-8 -*-
"""
删除 users.referred_by 冗余字段
优化绑定关系存储，只使用 referral_bindings 表
"""

import pymysql
import sys

# 数据库配置（从 lib/db.ts 获取）
DB_CONFIG = {
    'host': 'gz-cynosdbmysql-grp-kfcvxbby.sql.tencentcdb.com',
    'port': 27815,
    'user': 'root',
    'password': 'Aa112211',
    'database': 'soul_miniprogram',
    'charset': 'utf8mb4'
}

def print_step(step, msg):
    """打印步骤信息"""
    print('\n' + '=' * 70)
    print('步骤 {}: {}'.format(step, msg))
    print('=' * 70)

def execute_sql(cursor, sql, params=None):
    """执行SQL并返回影响行数"""
    try:
        if params:
            cursor.execute(sql, params)
        else:
            cursor.execute(sql)
        return cursor.rowcount
    except Exception as e:
        print('执行失败: {}'.format(str(e)))
        raise

def main():
    connection = None
    
    try:
        print_step(1, '连接数据库')
        connection = pymysql.connect(**DB_CONFIG)
        cursor = connection.cursor()
        print('已连接到数据库: {}'.format(DB_CONFIG['database']))
        
        # ========================================
        # 步骤2: 备份当前 referred_by 数据
        # ========================================
        print_step(2, '备份 referred_by 数据（用于验证）')
        
        cursor.execute('''
            SELECT 
                COUNT(*) as total,
                COUNT(referred_by) as has_referrer,
                COUNT(DISTINCT referred_by) as unique_referrers
            FROM users
        ''')
        stats = cursor.fetchone()
        print('当前用户表统计:')
        print('  总用户数: {}'.format(stats[0]))
        print('  有推荐人的用户: {}'.format(stats[1]))
        print('  唯一推荐人数: {}'.format(stats[2]))
        
        # 导出 referred_by 数据到临时表（备份）
        cursor.execute('DROP TABLE IF EXISTS users_referred_by_backup')
        cursor.execute('''
            CREATE TABLE users_referred_by_backup AS
            SELECT id, referred_by, created_at
            FROM users
            WHERE referred_by IS NOT NULL
        ''')
        backup_count = cursor.rowcount
        print('已备份 {} 条记录到 users_referred_by_backup 表'.format(backup_count))
        
        # ========================================
        # 步骤3: 验证 referral_bindings 数据完整性
        # ========================================
        print_step(3, '验证 referral_bindings 数据完整性')
        
        cursor.execute('''
            SELECT 
                COUNT(*) as total_bindings,
                COUNT(DISTINCT referee_id) as unique_referees,
                SUM(CASE WHEN status = 'active' THEN 1 ELSE 0 END) as active_bindings
            FROM referral_bindings
        ''')
        binding_stats = cursor.fetchone()
        print('推荐绑定表统计:')
        print('  总绑定记录: {}'.format(binding_stats[0]))
        print('  唯一被推荐人: {}'.format(binding_stats[1]))
        print('  当前活跃绑定: {}'.format(binding_stats[2]))
        
        # 检查数据一致性
        cursor.execute('''
            SELECT COUNT(*) FROM users u
            WHERE u.referred_by IS NOT NULL
              AND NOT EXISTS (
                SELECT 1 FROM referral_bindings rb
                WHERE rb.referee_id = u.id
              )
        ''')
        inconsistent = cursor.fetchone()[0]
        if inconsistent > 0:
            print('警告: 发现 {} 个用户在 users.referred_by 有值但 referral_bindings 中无记录'.format(inconsistent))
            print('这些记录可能是旧数据，删除字段后将丢失')
        else:
            print('数据一致性检查通过！')
        
        # ========================================
        # 步骤4: 删除 referred_by 相关索引
        # ========================================
        print_step(4, '删除 referred_by 索引')
        
        # 检查索引是否存在
        cursor.execute('''
            SELECT COUNT(*) FROM information_schema.statistics
            WHERE table_schema = %s
              AND table_name = 'users'
              AND index_name = 'idx_referred_by'
        ''', (DB_CONFIG['database'],))
        
        index_exists = cursor.fetchone()[0] > 0
        
        if index_exists:
            cursor.execute('ALTER TABLE users DROP INDEX idx_referred_by')
            print('已删除索引: idx_referred_by')
        else:
            print('索引 idx_referred_by 不存在，跳过')
        
        # ========================================
        # 步骤5: 删除 referred_by 字段
        # ========================================
        print_step(5, '删除 users.referred_by 字段')
        
        # 检查字段是否存在
        cursor.execute('''
            SELECT COUNT(*) FROM information_schema.columns
            WHERE table_schema = %s
              AND table_name = 'users'
              AND column_name = 'referred_by'
        ''', (DB_CONFIG['database'],))
        
        field_exists = cursor.fetchone()[0] > 0
        
        if field_exists:
            cursor.execute('ALTER TABLE users DROP COLUMN referred_by')
            print('已删除字段: users.referred_by')
        else:
            print('字段 referred_by 不存在，跳过')
        
        # ========================================
        # 步骤6: 提交更改
        # ========================================
        print_step(6, '提交数据库更改')
        connection.commit()
        print('所有更改已提交！')
        
        # ========================================
        # 步骤7: 验证删除结果
        # ========================================
        print_step(7, '验证删除结果')
        
        cursor.execute('''
            SELECT COUNT(*) FROM information_schema.columns
            WHERE table_schema = %s
              AND table_name = 'users'
              AND column_name = 'referred_by'
        ''', (DB_CONFIG['database'],))
        
        still_exists = cursor.fetchone()[0] > 0
        
        if still_exists:
            print('警告: 字段仍然存在！')
        else:
            print('验证通过: referred_by 字段已成功删除')
        
        # 检查备份表
        cursor.execute('SELECT COUNT(*) FROM users_referred_by_backup')
        backup_rows = cursor.fetchone()[0]
        print('备份表保留了 {} 条记录（可选择稍后删除）'.format(backup_rows))
        
        # ========================================
        # 完成
        # ========================================
        print('\n' + '=' * 70)
        print('优化完成！')
        print('=' * 70)
        print('\n后续步骤:')
        print('1. 修改代码中所有使用 referred_by 的地方')
        print('2. 部署新代码到服务器')
        print('3. 测试绑定和佣金功能')
        print('4. 确认无误后，可删除备份表: DROP TABLE users_referred_by_backup')
        print('\n备份表可保留一段时间，确保数据安全。')
        
    except Exception as e:
        print('\n错误: {}'.format(str(e)))
        if connection:
            connection.rollback()
            print('已回滚所有更改')
        sys.exit(1)
        
    finally:
        if connection:
            cursor.close()
            connection.close()
            print('\n数据库连接已关闭')

if __name__ == '__main__':
    print('\n' + '=' * 70)
    print('删除 users.referred_by 冗余字段')
    print('=' * 70)
    print('\n此脚本将执行以下操作:')
    print('1. 备份 referred_by 数据到 users_referred_by_backup 表')
    print('2. 删除 idx_referred_by 索引')
    print('3. 删除 users.referred_by 字段')
    print('\n警告: 此操作会修改数据库结构！')
    print('建议先在测试环境执行。')
    
    try:
        raw_input_func = raw_input  # Python 2
    except NameError:
        raw_input_func = input  # Python 3
    
    confirm = raw_input_func('\n确认执行？(输入 yes 继续): ')
    
    if confirm.lower() != 'yes':
        print('已取消操作')
        sys.exit(0)
    
    main()