#!/bin/bash
# verify_backup.sh - 验证备份完整性

set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
CONFIG_FILE="${SCRIPT_DIR}/backup_config.json"

log() { echo "[$(date '+%Y-%m-%d %H:%M:%S')] $1"; }

verify_backup_integrity() {
    local backup_file="$1"
    
    log "验证备份完整性: $backup_file"
    
    # 检查文件是否存在
    if [[ ! -f "$backup_file" ]]; then
        echo "❌ 备份文件不存在"
        return 1
    fi
    
    # 检查文件大小
    local file_size=$(stat -c%s "$backup_file")
    if [[ $file_size -eq 0 ]]; then
        echo "❌ 备份文件为空"
        return 1
    fi
    
    echo "✅ 文件大小: $(numfmt --to=iec-i --suffix=B $file_size)"
    
    # 检查tar归档完整性
    if tar -tzf "$backup_file" > /dev/null 2>&1; then
        echo "✅ 归档完整性验证通过"
        
        # 统计文件数量
        local file_count=$(tar -tzf "$backup_file" | wc -l)
        echo "✅ 包含文件数: $file_count"
        
        # 检查长路径文件
        local long_path_files=$(tar -tzf "$backup_file" | grep -c '/.\{100,\}')
        if [[ $long_path_files -gt 0 ]]; then
            echo "📁 长路径文件数: $long_path_files"
        fi
        
        return 0
    else
        echo "❌ 归档损坏或格式错误"
        return 1
    fi
}

# 主函数
main() {
    local backup_file="${1:-}"
    
    if [[ -z "$backup_file" ]]; then
        # 使用最新备份
        local backup_dir=$(jq -r '.storage.local_path // "/backups"' "$CONFIG_FILE")
        backup_file=$(find "$backup_dir" -name "backup_*.tar.gz" -o -name "backup_*.tar.gz.gpg" | sort | tail -1)
        
        if [[ -z "$backup_file" ]]; then
            echo "❌ 未找到备份文件"
            exit 1
        fi
    fi
    
    echo "🔍 备份验证报告"
    echo "========================================"
    echo "备份文件: $backup_file"
    echo "验证时间: $(date)"
    echo "----------------------------------------"
    
    if verify_backup_integrity "$backup_file"; then
        echo "✅ 备份验证通过"
        exit 0
    else
        echo "❌ 备份验证失败"
        exit 1
    fi
}

main "$@"