#!/bin/bash

# OCNGX 完整备份脚本
# 支持多环境部署的数据备份和恢复

set -euo pipefail

# 配置变量
SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
BACKUP_DIR="${BACKUP_DIR:-/var/backups/ocngx}"
BACKUP_DATE=$(date '+%Y%m%d_%H%M%S')
BACKUP_ID="ocngx_backup_${BACKUP_DATE}"
TEMP_BACKUP_DIR="/tmp/${BACKUP_ID}"

# 环境检测
detect_environment() {
    echo "🔍 检测运行环境..."
    
    if [[ -f /.dockerenv ]]; then
        ENVIRONMENT="docker"
        echo "  🐳 Docker 容器环境"
    elif [[ -d /app && -f /app/opencode.json ]]; then
        ENVIRONMENT="huggingface"
        echo "  🤗 HuggingFace Spaces 环境"
    else
        ENVIRONMENT="local"
        echo "  💻 本地环境"
    fi
    
    # 检测 OpenCode 安装位置
    if command -v opencode &> /dev/null; then
        OPENCODE_CMD="opencode"
        OPENCODE_DATA_DIR="${HOME}/.opencode"
    elif npm list -g opencode-ai &> /dev/null; then
        OPENCODE_CMD="opencode"
        OPENCODE_DATA_DIR="${HOME}/.opencode"
    else
        echo "  ❌ 未找到 OpenCode 安装"
        exit 1
    fi
    
    echo "  📂 OpenCode 数据目录: ${OPENCODE_DATA_DIR}"
}

# 创建备份目录
prepare_backup() {
    echo "📁 准备备份环境..."
    
    mkdir -p "$BACKUP_DIR"
    mkdir -p "$TEMP_BACKUP_DIR"
    
    # 创建备份元数据
    cat > "${TEMP_BACKUP_DIR}/backup_metadata.json" << EOF
{
    "backup_id": "${BACKUP_ID}",
    "backup_date": "$(date -Iseconds)",
    "environment": "${ENVIRONMENT}",
    "hostname": "$(hostname)",
    "opencode_version": "$(opencode --version 2>/dev/null || echo 'unknown')",
    "system_info": {
        "os": "$(uname -s)",
        "arch": "$(uname -m)",
        "kernel": "$(uname -r)"
    },
    "disk_usage": {
        "total": "$(df -h / | awk 'NR==2 {print $2}')",
        "used": "$(df -h / | awk 'NR==2 {print $3}')",
        "available": "$(df -h / | awk 'NR==2 {print $4}')"
    }
}
EOF
}

# 备份配置文件
backup_configs() {
    echo "⚙️ 备份配置文件..."
    
    local config_dir="${TEMP_BACKUP_DIR}/configs"
    mkdir -p "$config_dir"
    
    # 备份项目配置文件
    [[ -f "${SCRIPT_DIR}/opencode.json" ]] && cp "${SCRIPT_DIR}/opencode.json" "$config_dir/"
    [[ -f "${SCRIPT_DIR}/AGENT.md" ]] && cp "${SCRIPT_DIR}/AGENT.md" "$config_dir/"
    [[ -f "${SCRIPT_DIR}/docker-start.sh" ]] && cp "${SCRIPT_DIR}/docker-start.sh" "$config_dir/"
    [[ -f "${SCRIPT_DIR}/Dockerfile" ]] && cp "${SCRIPT_DIR}/Dockerfile" "$config_dir/"
    
    # 备份 Nginx 配置
    if [[ -d "${SCRIPT_DIR}/nginx" ]]; then
        cp -r "${SCRIPT_DIR}/nginx" "$config_dir/"
    fi
    
    # 备份 Cron 配置
    if [[ -d "${SCRIPT_DIR}/cron-jobs" ]]; then
        cp -r "${SCRIPT_DIR}/cron-jobs" "$config_dir/"
    fi
    
    # 备份环境变量（排除敏感信息）
    env | grep -E '^(OPENCODE_|PUBLIC_|BASE_|GATEWAY_)' > "$config_dir/environment.txt" 2>/dev/null || true
    
    echo "  ✅ 配置文件备份完成"
}

# 备份 OpenCode 数据
backup_opencode_data() {
    echo "🤖 备份 OpenCode 数据..."
    
    if [[ -d "$OPENCODE_DATA_DIR" ]]; then
        local data_dir="${TEMP_BACKUP_DIR}/opencode_data"
        mkdir -p "$data_dir"
        
        # 备份核心数据目录
        for subdir in "projects" "sessions" "config" "cache" "logs"; do
            if [[ -d "${OPENCODE_DATA_DIR}/${subdir}" ]]; then
                cp -r "${OPENCODE_DATA_DIR}/${subdir}" "$data_dir/"
                echo "  📦 已备份: $subdir"
            fi
        done
        
        # 备份全局配置文件
        [[ -f "${OPENCODE_DATA_DIR}/config.json" ]] && cp "${OPENCODE_DATA_DIR}/config.json" "$data_dir/"
        [[ -f "${OPENCODE_DATA_DIR}/preferences.json" ]] && cp "${OPENCODE_DATA_DIR}/preferences.json" "$data_dir/"
        
        echo "  ✅ OpenCode 数据备份完成"
    else
        echo "  ⚠️ OpenCode 数据目录不存在，跳过"
    fi
}

# 备份运行时状态
backup_runtime_state() {
    echo "🔄 备份运行时状态..."
    
    local runtime_dir="${TEMP_BACKUP_DIR}/runtime"
    mkdir -p "$runtime_dir"
    
    # 备份当前运行的进程信息
    ps aux | grep -E "(opencode|nginx|openresty)" > "$runtime_dir/running_processes.txt" 2>/dev/null || true
    
    # 备份网络连接状态
    netstat -tlnp 2>/dev/null | grep -E ":(3000|7860)" > "$runtime_dir/network_state.txt" || true
    
    # 备份最近的日志
    if [[ -d "/var/log" ]]; then
        find /var/log -name "*nginx*" -o -name "*opencode*" -mtime -7 -exec cp {} "$runtime_dir/" \; 2>/dev/null || true
    fi
    
    echo "  ✅ 运行时状态备份完成"
}

# 创建备份归档
create_archive() {
    echo "🗜️ 创建备份归档..."
    
    local archive_file="${BACKUP_DIR}/${BACKUP_ID}.tar.gz"
    
    # 创建压缩归档
    tar -czf "$archive_file" -C "/tmp" "$BACKUP_ID"
    
    # 验证归档
    if [[ -f "$archive_file" ]]; then
        local archive_size=$(du -h "$archive_file" | cut -f1)
        echo "  ✅ 备份归档创建成功: ${archive_file} (${archive_size})"
        
        # 生成校验和
        sha256sum "$archive_file" > "${archive_file}.sha256"
        echo "  🔐 校验和已生成: ${archive_file}.sha256"
    else
        echo "  ❌ 备份归档创建失败"
        exit 1
    fi
}

# 清理旧备份
cleanup_old_backups() {
    echo "🧹 清理旧备份..."
    
    cd "$BACKUP_DIR"
    
    # 保留最近 10 个备份
    local backup_count=$(ls -1 ocngx_backup_*.tar.gz 2>/dev/null | wc -l)
    if [[ $backup_count -gt 10 ]]; then
        echo "  🗑️ 删除超过 10 个的旧备份..."
        ls -t ocngx_backup_*.tar.gz 2>/dev/null | tail -n +11 | while read -r old_backup; do
            echo "    删除: $old_backup"
            rm -f "$old_backup" "${old_backup}.sha256"
        done
    fi
    
    # 显示备份状态
    local remaining_count=$(ls -1 ocngx_backup_*.tar.gz 2>/dev/null | wc -l)
    local total_size=$(du -sh "$BACKUP_DIR" 2>/dev/null | cut -f1)
    echo "  📊 当前备份状态: $remaining_count 个文件, 总大小: $total_size"
}

# 上传到外部存储（可选）
upload_to_external() {
    if [[ -n "${BACKUP_S3_BUCKET:-}" ]]; then
        echo "☁️ 上传备份到 S3..."
        
        local archive_file="${BACKUP_DIR}/${BACKUP_ID}.tar.gz"
        
        if command -v aws &> /dev/null; then
            aws s3 cp "$archive_file" "s3://${BACKUP_S3_BUCKET}/ocngx-backups/" --storage-class STANDARD_IA
            aws s3 cp "${archive_file}.sha256" "s3://${BACKUP_S3_BUCKET}/ocngx-backups/"
            echo "  ✅ S3 上传完成"
        else
            echo "  ⚠️ AWS CLI 未安装，跳过 S3 上传"
        fi
    fi
}

# 主函数
main() {
    echo "🚀 OCNGX 完整备份开始..."
    echo "📅 备份时间: $(date '+%Y-%m-%d %H:%M:%S')"
    echo "🆔 备份ID: ${BACKUP_ID}"
    echo ""
    
    detect_environment
    prepare_backup
    backup_configs
    backup_opencode_data
    backup_runtime_state
    create_archive
    cleanup_old_backups
    upload_to_external
    
    # 清理临时目录
    rm -rf "$TEMP_BACKUP_DIR"
    
    echo ""
    echo "✅ 备份完成!"
    echo "📁 备份位置: ${BACKUP_DIR}/${BACKUP_ID}.tar.gz"
    echo "🔍 验证命令: tar -tzf ${BACKUP_DIR}/${BACKUP_ID}.tar.gz | head -10"
}

# 执行主函数
main "$@"