#!/bin/bash

# 考培练系统自动更新脚本
# 作者: AI Assistant  
# 日期: 2025-09-25

set -e

# 配置变量
PROJECT_DIR="/root/aiedu"
LOG_FILE="/var/log/kaopeilian_update.log"
BACKUP_DIR="/root/aiedu/backups/updates"

# 日志函数
log() {
    echo "[$(date '+%Y-%m-%d %H:%M:%S')] $1" | tee -a "$LOG_FILE"
}

# 创建备份目录
mkdir -p "$BACKUP_DIR"

log "=== 开始检查代码更新 ==="

cd "$PROJECT_DIR"

# 获取当前提交哈希
LOCAL_COMMIT=$(git rev-parse HEAD)
log "本地提交: $LOCAL_COMMIT"

# 拉取最新代码
git fetch origin production

# 获取远程提交哈希  
REMOTE_COMMIT=$(git rev-parse origin/production)
log "远程提交: $REMOTE_COMMIT"

# 检查是否有更新
if [ "$LOCAL_COMMIT" = "$REMOTE_COMMIT" ]; then
    log "代码已是最新版本，无需更新"
    exit 0
fi

log "发现代码更新，开始部署流程..."

# 创建备份
BACKUP_NAME="backup_$(date '+%Y%m%d_%H%M%S')"
log "创建备份: $BACKUP_NAME"

# 备份当前代码
git stash push -m "Auto backup before update $BACKUP_NAME"

# 备份数据库（如果MySQL容器在运行）
if docker ps | grep -q kaopeilian-mysql; then
    docker exec kaopeilian-mysql mysqldump -u root -p'Kaopeilian2025!@#' kaopeilian > "$BACKUP_DIR/${BACKUP_NAME}_database.sql"
    log "数据库备份完成"
fi

# 拉取最新代码
log "拉取最新代码..."
git pull origin production

# 检查是否需要重新构建
NEED_REBUILD=false

# 检查Docker文件变化
if git diff --name-only "$LOCAL_COMMIT" "$REMOTE_COMMIT" | grep -E "(Dockerfile|docker-compose\.yml|requirements\.txt|package\.json)"; then
    NEED_REBUILD=true
    log "检测到构建文件变化，需要重新构建镜像"
fi

# 检查前端文件变化并构建
if git diff --name-only "$LOCAL_COMMIT" "$REMOTE_COMMIT" | grep -E "kaopeilian-frontend/(src/|package\.json|vite\.config\.ts)"; then
    log "检测到前端代码变化，开始构建前端..."
    
    cd "$PROJECT_DIR/kaopeilian-frontend"
    
    # 确保依赖已安装
    if [ ! -d "node_modules" ]; then
        log "安装前端依赖..."
        npm install
    fi
    
    # 构建前端
    log "构建前端应用..."
    npm run build
    
    if [ $? -eq 0 ]; then
        log "前端构建成功"
        NEED_REBUILD=true
    else
        log "⚠️  前端构建失败，但继续部署流程"
    fi
    
    cd "$PROJECT_DIR"
fi

# 停止服务
log "停止当前服务..."
docker compose down

# 重新构建（如果需要）
if [ "$NEED_REBUILD" = true ]; then
    log "重新构建Docker镜像..."
    docker compose build --no-cache
else
    log "使用现有镜像启动服务..."
fi

# 启动服务
log "启动更新后的服务..."
docker compose up -d

# 等待服务启动
sleep 60

# 健康检查
log "执行健康检查..."
HEALTH_CHECK_URL="https://aiedu.ireborn.com.cn/health"

# 尝试多次健康检查
RETRY_COUNT=0
MAX_RETRIES=5

while [ $RETRY_COUNT -lt $MAX_RETRIES ]; do
    if curl -f -s -k "$HEALTH_CHECK_URL" > /dev/null; then
        log "✅ 健康检查通过，更新成功完成"
        
        # 清理旧的备份（保留最近5个）
        cd "$BACKUP_DIR"
        ls -t backup_*_database.sql 2>/dev/null | tail -n +6 | xargs rm -f 2>/dev/null || true
        
        log "=== 自动更新完成 ==="
        exit 0
    else
        RETRY_COUNT=$((RETRY_COUNT + 1))
        log "健康检查失败，重试 $RETRY_COUNT/$MAX_RETRIES"
        sleep 10
    fi
done

log "❌ 健康检查失败，开始回滚..."

# 回滚代码
cd "$PROJECT_DIR"
git reset --hard "$LOCAL_COMMIT"

# 重新启动服务
docker compose down
docker compose up -d

log "回滚完成，请检查服务状态"
exit 1