#!/bin/bash

################################################################################
# FLNXI素材库共享平台 - 数据库自动备份脚本
# 功能：自动备份PostgreSQL数据库（不包含源素材文件）
# 使用：./backup-database.sh
################################################################################

# 配置
BACKUP_DIR="/mnt/PoolOne/backups/youyidian-3d"
DB_HOST="192.168.58.20"
DB_PORT="5432"
DB_NAME="lobechat"
DB_USER="gongxiangpan"
DB_PASS="gongxiangpan123"
KEEP_DAYS=30  # 保留最近30天的备份

# 颜色输出
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
NC='\033[0m' # No Color

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

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

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

# 创建备份目录
create_backup_dirs() {
    log_info "创建备份目录..."
    mkdir -p "$BACKUP_DIR/database"
    mkdir -p "$BACKUP_DIR/logs"
}

# 备份数据库
backup_database() {
    local timestamp=$(date +%Y%m%d_%H%M%S)
    local backup_file="$BACKUP_DIR/database/db_backup_${timestamp}.sql.gz"
    
    log_info "开始备份数据库..."
    
    # 使用Docker运行pg_dump
    docker run --rm \
        -e PGPASSWORD="$DB_PASS" \
        postgres:15-alpine \
        pg_dump \
        -h "$DB_HOST" \
        -p "$DB_PORT" \
        -U "$DB_USER" \
        -d "$DB_NAME" \
        --no-owner \
        --no-acl \
        2>/dev/null | gzip > "$backup_file"
    
    if [ $? -eq 0 ] && [ -f "$backup_file" ]; then
        local size=$(du -h "$backup_file" | cut -f1)
        log_info "数据库备份成功: $backup_file (大小: $size)"
        return 0
    else
        log_error "数据库备份失败"
        rm -f "$backup_file"
        return 1
    fi
}

# 清理旧备份
cleanup_old_backups() {
    log_info "清理超过 ${KEEP_DAYS} 天的旧备份..."
    
    # 清理数据库备份
    local db_deleted=$(find "$BACKUP_DIR/database" -name "db_backup_*.sql.gz" -mtime +$KEEP_DAYS -delete -print | wc -l)
    if [ $db_deleted -gt 0 ]; then
        log_info "删除了 $db_deleted 个旧数据库备份"
    fi
    
    # 清理旧日志
    find "$BACKUP_DIR/logs" -name "backup_*.log" -mtime +$KEEP_DAYS -delete
}

# 生成备份报告
generate_report() {
    local report_file="$BACKUP_DIR/logs/backup_$(date +%Y%m%d_%H%M%S).log"
    
    cat > "$report_file" << EOF
================================================================================
数据库备份报告
================================================================================
备份时间: $(date '+%Y-%m-%d %H:%M:%S')
数据库: $DB_NAME@$DB_HOST:$DB_PORT

--- 备份统计 ---
数据库备份数量: $(ls -1 "$BACKUP_DIR/database" 2>/dev/null | wc -l)
最旧备份: $(ls -t "$BACKUP_DIR/database" 2>/dev/null | tail -n 1 | xargs stat -c %y 2>/dev/null | cut -d' ' -f1)
最新备份: $(ls -t "$BACKUP_DIR/database" 2>/dev/null | head -n 1 | xargs stat -c %y 2>/dev/null | cut -d' ' -f1)

--- 磁盘使用 ---
数据库备份占用: $(du -sh "$BACKUP_DIR/database" 2>/dev/null | cut -f1)
总计占用: $(du -sh "$BACKUP_DIR" 2>/dev/null | cut -f1)

--- 最新5个备份 ---
$(ls -lht "$BACKUP_DIR/database" 2>/dev/null | head -n 6 | tail -n 5)

================================================================================
EOF

    log_info "备份报告已生成: $report_file"
}

# 测试数据库连接
test_connection() {
    log_info "测试数据库连接..."
    
    docker run --rm \
        -e PGPASSWORD="$DB_PASS" \
        postgres:15-alpine \
        psql \
        -h "$DB_HOST" \
        -p "$DB_PORT" \
        -U "$DB_USER" \
        -d "$DB_NAME" \
        -c "SELECT 1;" >/dev/null 2>&1
    
    if [ $? -eq 0 ]; then
        log_info "数据库连接成功"
        return 0
    else
        log_error "数据库连接失败"
        return 1
    fi
}

# 主函数
main() {
    echo ""
    echo "========================================"
    echo "  FLNXI素材库 - 数据库备份"
    echo "========================================"
    echo ""
    
    # 测试连接
    if ! test_connection; then
        log_error "备份终止：无法连接到数据库"
        exit 1
    fi
    
    # 创建目录
    create_backup_dirs
    
    # 执行备份
    local db_status=0
    
    backup_database || db_status=1
    
    # 清理旧备份
    cleanup_old_backups
    
    # 生成报告
    generate_report
    
    # 汇总结果
    echo ""
    echo "========================================"
    echo "  备份完成"
    echo "========================================"
    
    if [ $db_status -eq 0 ]; then
        log_info "数据库备份任务成功完成"
        exit 0
    else
        log_error "数据库备份任务失败"
        exit 1
    fi
}

# 执行主函数
main "$@"