#!/bin/bash

# MySQL清理和重新安装脚本
# 作者: emotion-museum
# 日期: 2025-07-21
# 功能: 清理现有MySQL组件，保留数据文件，重新安装MySQL

set -e

REMOTE_HOST="root@47.111.10.27"
MYSQL_DATA_DIR="/data/programs/mysql"
MYSQL_ROOT_PASSWORD="EmotionMuseum2025*#"

# 颜色输出
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
BLUE='\033[0;34m'
NC='\033[0m'

log_info() {
    echo -e "${BLUE}[INFO]${NC} $(date '+%Y-%m-%d %H:%M:%S') - $1"
}

log_success() {
    echo -e "${GREEN}[SUCCESS]${NC} $(date '+%Y-%m-%d %H:%M:%S') - $1"
}

log_warning() {
    echo -e "${YELLOW}[WARNING]${NC} $(date '+%Y-%m-%d %H:%M:%S') - $1"
}

log_error() {
    echo -e "${RED}[ERROR]${NC} $(date '+%Y-%m-%d %H:%M:%S') - $1"
}

# 检查SSH连接
check_connection() {
    log_info "检查远程服务器连接..."
    if ssh -o ConnectTimeout=10 "$REMOTE_HOST" "echo 'SSH连接成功'" > /dev/null 2>&1; then
        log_success "远程服务器连接正常"
    else
        log_error "无法连接到远程服务器: $REMOTE_HOST"
        exit 1
    fi
}

# 备份数据文件
backup_data_files() {
    log_info "备份MySQL数据文件..."
    
    ssh "$REMOTE_HOST" "
        echo '📦 备份数据文件...'
        BACKUP_DIR=\"/data/backups/mysql_data_\$(date +%Y%m%d_%H%M%S)\"
        mkdir -p \"\$BACKUP_DIR\"
        
        # 备份数据目录
        if [ -d '$MYSQL_DATA_DIR' ]; then
            cp -r $MYSQL_DATA_DIR \"\$BACKUP_DIR/\"
            echo \"✅ 数据文件已备份到: \$BACKUP_DIR\"
        else
            echo '⚠️ 数据目录不存在: $MYSQL_DATA_DIR'
        fi
        
        # 导出数据库（如果Docker容器还在运行）
        if docker ps | grep -q emotion-mysql; then
            echo '📤 导出数据库...'
            docker exec emotion-mysql mysqldump -u root -p'$MYSQL_ROOT_PASSWORD' --all-databases --routines --triggers > \"\$BACKUP_DIR/all_databases.sql\" || echo '数据库导出失败'
        fi
    "
    
    log_success "数据文件备份完成"
}

# 停止并清理Docker MySQL
cleanup_docker_mysql() {
    log_info "停止并清理Docker MySQL..."
    
    ssh "$REMOTE_HOST" "
        echo '🛑 停止Docker MySQL容器...'
        docker stop emotion-mysql 2>/dev/null || echo 'MySQL容器已停止'
        docker rm emotion-mysql 2>/dev/null || echo 'MySQL容器已删除'
        
        echo '🗑️ 删除MySQL Docker镜像...'
        docker rmi mysql:8.0 2>/dev/null || echo 'MySQL镜像不存在或被其他容器使用'
        
        echo '✅ Docker MySQL清理完成'
    "
    
    log_success "Docker MySQL清理完成"
}

# 清理现有MySQL组件
cleanup_existing_mysql() {
    log_info "清理现有MySQL组件..."
    
    ssh "$REMOTE_HOST" "
        echo '🧹 停止现有MySQL服务...'
        systemctl stop mysqld 2>/dev/null || echo 'mysqld服务未运行'
        systemctl stop mysql 2>/dev/null || echo 'mysql服务未运行'
        
        echo '🗑️ 卸载现有MySQL和MariaDB包...'
        # 卸载MySQL相关包（保留数据）
        yum remove -y mysql-community-server mysql-community-client mysql-community-common mysql-community-libs 2>/dev/null || echo 'MySQL社区版包不存在'
        yum remove -y mysql-server mysql-client mysql-common mysql-libs 2>/dev/null || echo 'MySQL包不存在'
        yum remove -y bt-mysql80 2>/dev/null || echo 'bt-mysql80包不存在'
        
        # 卸载MariaDB包
        yum remove -y mariadb mariadb-server mariadb-libs mariadb-common mariadb-connector-c 2>/dev/null || echo 'MariaDB包不存在'
        
        echo '🗑️ 清理配置文件...'
        # 备份并清理配置文件
        if [ -d '/etc/mysql' ]; then
            mv /etc/mysql /etc/mysql.bak.\$(date +%Y%m%d_%H%M%S) 2>/dev/null || true
        fi
        if [ -d '/etc/my.cnf.d' ]; then
            mv /etc/my.cnf.d /etc/my.cnf.d.bak.\$(date +%Y%m%d_%H%M%S) 2>/dev/null || true
        fi
        if [ -f '/etc/my.cnf' ]; then
            mv /etc/my.cnf /etc/my.cnf.bak.\$(date +%Y%m%d_%H%M%S) 2>/dev/null || true
        fi
        
        echo '🗑️ 清理日志文件...'
        rm -rf /var/log/mysql* 2>/dev/null || true
        rm -rf /var/log/mysqld* 2>/dev/null || true
        
        echo '🗑️ 清理运行时文件...'
        rm -rf /var/run/mysqld* 2>/dev/null || true
        rm -rf /tmp/mysql* 2>/dev/null || true
        
        echo '✅ 现有MySQL组件清理完成'
    "
    
    log_success "现有MySQL组件清理完成"
}

# 下载并安装MySQL仓库
install_mysql_repo() {
    log_info "下载并安装MySQL仓库..."
    
    ssh "$REMOTE_HOST" "
        echo '📥 下载MySQL仓库配置包...'
        cd /tmp
        wget -O mysql80-community-release-el8-3.noarch.rpm https://repo.huaweicloud.com/mysql/Downloads/mysql-8.0/mysql80-community-release-el8-3.noarch.rpm
        
        if [ -f 'mysql80-community-release-el8-3.noarch.rpm' ]; then
            echo '✅ MySQL仓库配置包下载成功'
            ls -la mysql80-community-release-el8-3.noarch.rpm
        else
            echo '❌ MySQL仓库配置包下载失败'
            exit 1
        fi
        
        echo '📦 安装MySQL仓库配置...'
        yum localinstall -y mysql80-community-release-el8-3.noarch.rpm
        
        echo '🔄 更新yum缓存...'
        yum clean all
        yum makecache
        
        echo '✅ MySQL仓库安装完成'
    "
    
    log_success "MySQL仓库安装完成"
}

# 安装MySQL服务器
install_mysql_server() {
    log_info "安装MySQL服务器..."
    
    ssh "$REMOTE_HOST" "
        echo '📦 安装MySQL社区服务器...'
        yum install -y mysql-community-server mysql-community-client
        
        # 检查安装结果
        if command -v mysql >/dev/null 2>&1 && command -v mysqld >/dev/null 2>&1; then
            echo '✅ MySQL服务器安装成功'
            mysql --version
            mysqld --version
        else
            echo '❌ MySQL服务器安装失败'
            exit 1
        fi
    "
    
    log_success "MySQL服务器安装完成"
}

# 配置MySQL使用现有数据
configure_mysql_with_existing_data() {
    log_info "配置MySQL使用现有数据..."
    
    ssh "$REMOTE_HOST" "
        echo '⚙️ 创建MySQL配置文件...'
        cat > /etc/my.cnf << 'EOF'
[mysqld]
# 数据目录
datadir = /data/programs/mysql
socket = /var/lib/mysql/mysql.sock

# 网络配置
bind-address = 0.0.0.0
port = 3306

# 字符集配置
character-set-server = utf8mb4
collation-server = utf8mb4_unicode_ci

# 认证插件
default-authentication-plugin = mysql_native_password

# 日志配置
log-error = /var/log/mysqld.log
pid-file = /var/run/mysqld/mysqld.pid

# 性能配置
max_connections = 200
innodb_buffer_pool_size = 512M

# 安全配置
skip-name-resolve

# 二进制日志
log-bin = mysql-bin
binlog_format = ROW
expire_logs_days = 7

[mysql]
default-character-set = utf8mb4

[client]
default-character-set = utf8mb4
socket = /var/lib/mysql/mysql.sock
EOF
        
        echo '📁 配置数据目录权限...'
        # 创建mysql用户（如果不存在）
        id mysql >/dev/null 2>&1 || useradd -r -s /bin/false mysql
        
        # 设置数据目录权限
        chown -R mysql:mysql $MYSQL_DATA_DIR
        chmod -R 750 $MYSQL_DATA_DIR
        
        # 创建必要的目录
        mkdir -p /var/lib/mysql
        mkdir -p /var/run/mysqld
        mkdir -p /var/log
        chown mysql:mysql /var/lib/mysql
        chown mysql:mysql /var/run/mysqld
        touch /var/log/mysqld.log
        chown mysql:mysql /var/log/mysqld.log
        
        echo '✅ MySQL配置完成'
    "
    
    log_success "MySQL配置完成"
}

# 启动MySQL服务
start_mysql_service() {
    log_info "启动MySQL服务..."
    
    ssh "$REMOTE_HOST" "
        echo '🚀 启动MySQL服务...'
        systemctl start mysqld
        systemctl enable mysqld
        
        # 等待MySQL启动
        sleep 10
        
        # 检查MySQL状态
        if systemctl is-active --quiet mysqld; then
            echo '✅ MySQL服务启动成功'
        else
            echo '❌ MySQL服务启动失败'
            systemctl status mysqld
            tail -20 /var/log/mysqld.log
            exit 1
        fi
        
        echo '🔍 检查端口监听...'
        if netstat -tlnp | grep :3306 > /dev/null; then
            echo '✅ MySQL端口3306正在监听'
        else
            echo '⚠️ MySQL端口3306未监听'
        fi
    "
    
    log_success "MySQL服务启动完成"
}

# 验证数据完整性
verify_data_integrity() {
    log_info "验证数据完整性..."
    
    ssh "$REMOTE_HOST" "
        echo '🔍 尝试连接MySQL...'
        # 由于使用现有数据，root密码应该已经设置
        if mysql -u root -p'$MYSQL_ROOT_PASSWORD' -e 'SELECT VERSION();' > /dev/null 2>&1; then
            echo '✅ MySQL连接成功，密码正确'
        else
            echo '⚠️ 使用现有密码连接失败，可能需要重置密码'
            
            # 获取临时密码（如果有）
            TEMP_PASSWORD=\$(grep 'temporary password' /var/log/mysqld.log | tail -1 | awk '{print \$NF}' 2>/dev/null || echo '')
            
            if [ -n \"\$TEMP_PASSWORD\" ]; then
                echo \"发现临时密码，尝试重置...\"
                mysql -u root -p\"\$TEMP_PASSWORD\" --connect-expired-password << 'EOSQL'
ALTER USER 'root'@'localhost' IDENTIFIED BY '$MYSQL_ROOT_PASSWORD';
FLUSH PRIVILEGES;
EOSQL
                echo '✅ 密码重置完成'
            else
                echo '⚠️ 未找到临时密码，可能需要手动处理'
            fi
        fi
        
        echo '🔍 检查数据库列表...'
        mysql -u root -p'$MYSQL_ROOT_PASSWORD' -e 'SHOW DATABASES;' || echo '数据库列表查询失败'
        
        echo '🔍 检查emotion_museum数据库...'
        mysql -u root -p'$MYSQL_ROOT_PASSWORD' -e 'USE emotion_museum; SHOW TABLES;' || echo 'emotion_museum数据库检查失败'
    "
    
    log_success "数据完整性验证完成"
}

# 检查最终状态
check_final_status() {
    log_info "检查最终状态..."
    
    ssh "$REMOTE_HOST" "
        echo '📊 MySQL服务状态:'
        echo '=================='
        
        # 检查服务状态
        echo -n 'MySQL服务: '
        if systemctl is-active --quiet mysqld; then
            echo '✅ 运行中'
        else
            echo '❌ 未运行'
        fi
        
        # 检查端口监听
        echo -n 'MySQL端口(3306): '
        if netstat -tlnp | grep :3306 | grep -v docker > /dev/null; then
            echo '✅ 监听中'
        else
            echo '❌ 未监听'
        fi
        
        # 检查进程
        echo -n 'MySQL进程: '
        if pgrep -f mysqld > /dev/null; then
            echo '✅ 运行中'
        else
            echo '❌ 未运行'
        fi
        
        echo ''
        echo '🔍 数据目录:'
        ls -la $MYSQL_DATA_DIR | head -5
        
        echo ''
        echo '🔍 配置文件:'
        ls -la /etc/my.cnf 2>/dev/null || echo '配置文件不存在'
    "
    
    log_success "状态检查完成"
}

# 主函数
main() {
    log_info "🚀 开始MySQL清理和重新安装..."
    
    echo "⚠️  此操作将："
    echo "  1. 备份现有MySQL数据文件"
    echo "  2. 停止并清理Docker MySQL"
    echo "  3. 清理现有MySQL/MariaDB组件"
    echo "  4. 下载并安装MySQL 8.0仓库"
    echo "  5. 安装MySQL社区服务器"
    echo "  6. 配置MySQL使用现有数据"
    echo "  7. 启动MySQL服务"
    echo ""
    echo "⚠️  数据文件将被保留，但配置文件将被重置"
    echo ""
    echo "是否继续？(y/N)"
    read -r confirm
    if [[ ! "$confirm" =~ ^[Yy]$ ]]; then
        log_warning "操作已取消"
        exit 0
    fi
    
    check_connection
    backup_data_files
    cleanup_docker_mysql
    cleanup_existing_mysql
    install_mysql_repo
    install_mysql_server
    configure_mysql_with_existing_data
    start_mysql_service
    verify_data_integrity
    check_final_status
    
    log_success "🎉 MySQL重新安装完成！"
    echo ""
    echo "📋 安装结果:"
    echo "  ✅ MySQL 8.0社区版已安装"
    echo "  ✅ 现有数据文件已保留"
    echo "  ✅ 服务正常运行"
    echo ""
    echo "📋 连接信息:"
    echo "  主机: localhost 或 47.111.10.27"
    echo "  端口: 3306"
    echo "  用户: root"
    echo "  密码: $MYSQL_ROOT_PASSWORD"
    echo "  数据库: emotion_museum"
    echo ""
    echo "🔧 下一步:"
    echo "  1. 测试应用连接"
    echo "  2. 重启微服务: cd backend && ./deploy-remote.sh"
}

# 执行主函数
main "$@"