#!/bin/bash
# ==============================================================================
# Guest Agent VM Image Injection Tool
# ==============================================================================
# 功能：将 guest_agent 组件注入到虚拟机镜像中，并配置开机自启
#
# 环境要求：
#   - libguestfs-tools / guestfs-tools 已安装
#
# 注入内容：
#   1. virtcca_deploy 完整代码 -> /opt/virtcca/
#   2. Python 虚拟环境 + 依赖安装
#   3. .env 配置文件
#   4. systemd service 文件 -> /etc/systemd/system/
#   5. SSL 证书（可选）-> /etc/virtcca_deploy/cert/
#   6. ifcfg 模板文件 -> /etc/sysconfig/network-scripts/
#
# 使用示例：
#   # 不启用 SSL
#   ./inject_guest_agent.sh -i /var/lib/libvirt/images/vm.qcow2
#
#   # 启用 SSL
#   ./inject_guest_agent.sh -i /var/lib/libvirt/images/vm.qcow2 \
#       --ssl \
#       --ssl-cert /etc/virtcca_deploy/cert/agent.crt \
#       --ssl-key /etc/virtcca_deploy/cert/agent.key
# ==============================================================================

set -euo pipefail

# ==============================================================================
# 全局变量
# ==============================================================================
VIRTCCA_DEPLOY_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")/../src/virtcca_deploy/" && pwd)"
GUEST_AGENT_DIR="$VIRTCCA_DEPLOY_DIR/guest_agent"
SCRIPTS_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
SCRIPT_NAME="$(basename "$0")"
SCRIPT_PID=$$
START_TIME=$(date +%s)
START_TIME_HUMAN=$(date '+%Y-%m-%d %H:%M:%S')
LOG_FILE="/tmp/inject_guest_agent_${SCRIPT_PID}.log"
TEMP_DIR=""
STEP_COUNT=0
TOTAL_STEPS=5
ERROR_COUNT=0
WARN_COUNT=0

# 颜色输出
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
BLUE='\033[0;34m'
CYAN='\033[0;36m'
NC='\033[0m'

# 默认参数
IMAGE_PATH="/etc/virtcca_deploy/base.qcow2"
INSTALL_DIR="/opt/virtcca"
SSL_ENABLED="true"
SSL_CERT_SRC=""
SSL_KEY_SRC=""
SSL_CA_CERT_SRC=""
SSL_CERT_PATH=""
SSL_KEY_PATH=""
SSL_CA_CERT_PATH=""
SSL_CERT_VM_DIR="/etc/virtcca_deploy/cert"
DRY_RUN="false"
KEEP_TEMP="false"

# ==============================================================================
# 结构化日志函数
# ==============================================================================
# 日志格式: [TIMESTAMP] [LEVEL] [MODULE] [PID] message
log_msg() {
    local level="$1"
    local module="$2"
    local message="$3"
    local timestamp
    timestamp=$(date '+%Y-%m-%d %H:%M:%S')
    local log_line="[${timestamp}] [${level}] [${module}] [PID:${SCRIPT_PID}] ${message}"
    
    case "$level" in
        INFO)  echo -e "${GREEN}${log_line}${NC}" ;;
        WARN)  echo -e "${YELLOW}${log_line}${NC}"; ((WARN_COUNT++)) ;;
        ERROR) echo -e "${RED}${log_line}${NC}"; ((ERROR_COUNT++)) ;;
        DEBUG) echo -e "${CYAN}${log_line}${NC}" ;;
        STEP)  echo -e "${BLUE}--- ${log_line} ---${NC}" ;;
    esac
    
    echo "$log_line" >> "$LOG_FILE"
}

log_info()  { log_msg "INFO"  "$1" "$2"; }
log_warn()  { log_msg "WARN"  "$1" "$2"; }
log_error() { log_msg "ERROR" "$1" "$2"; }
log_debug() { log_msg "DEBUG" "$1" "$2"; }
log_step()  { log_msg "STEP"  "$1" "$2"; }

# 记录错误并退出
die() {
    log_error "${1:-"Unknown error"}" "${2:-""}"
    exit 1
}

# 计时器
declare -A STEP_TIMES
start_timer() {
    STEP_TIMES["$1"]=$(date +%s)
}

stop_timer() {
    local step="$1"
    local end_time
    end_time=$(date +%s)
    local start=${STEP_TIMES["$step"]:-$end_time}
    echo $((end_time - start))
}

# ==============================================================================
# 显示帮助信息
# ==============================================================================
show_usage() {
    echo -e "${BLUE}Guest Agent VM Image Injection Tool${NC}"
    echo ""
    echo "Usage: $0 -i <image_path> [options]"
    echo ""
    echo "Options:"
    echo "  -i <path>       虚拟机镜像路径 (qcow2 格式)"
    echo "  -d <dir>        虚机内安装目录 (默认: /opt/virtcca/guest_agent)"
    echo "  --ssl           启用 SSL 加密通信"
    echo "  --ssl-cert-src <p>  宿主机 SSL 证书文件路径 (将被复制到虚机)"
    echo "  --ssl-key-src <p>   宿主机 SSL 私钥文件路径 (将被复制到虚机)"
    echo "  --ssl-ca-src <p>    宿主机 SSL CA 证书文件路径 (可选, 将被复制到虚机)"
    echo "  --ssl-cert-vm-dir <d> 虚机内证书存放目录 (默认: /etc/virtcca_deploy/cert)"
    echo "  --ssl-cert <p>  SSL 证书路径 (虚机内路径, 如不指定则使用 --ssl-cert-src)"
    echo "  --ssl-key <p>   SSL 私钥路径 (虚机内路径, 如不指定则使用 --ssl-key-src)"
    echo "  --ssl-ca <p>    SSL CA 证书路径 (虚机内路径, 可选)"
    echo "  --dry-run       仅检查环境并准备文件，不执行注入"
    echo "  -h              显示帮助信息"
    echo ""
    echo "Example:"
    echo "  $0 -i /etc/virtcca_deploy/base.qcow2"
    echo "  $0 -i /etc/virtcca_deploy/base.qcow2 --ssl --ssl-cert-src /path/to/agent.crt --ssl-key-src /path/to/agent.key"
    echo "  $0 -i /etc/virtcca_deploy/base.qcow2 --ssl --ssl-cert-src /path/to/agent.crt --ssl-key-src /path/to/agent.key --ssl-ca-src /path/to/ca.crt"
}

# ==============================================================================
# 解析命令行参数
# ==============================================================================
parse_args() {
    log_step "PARAM" "Parsing command line arguments"
    
    while [[ $# -gt 0 ]]; do
        case $1 in
            -i) IMAGE_PATH="$2"; shift 2 ;;
            -d) INSTALL_DIR="$2"; shift 2 ;;
            --ssl) SSL_ENABLED="true"; shift ;;
            --ssl-cert-src) SSL_CERT_SRC="$2"; shift 2 ;;
            --ssl-key-src) SSL_KEY_SRC="$2"; shift 2 ;;
            --ssl-ca-src) SSL_CA_CERT_SRC="$2"; shift 2 ;;
            --ssl-cert-vm-dir) SSL_CERT_VM_DIR="$2"; shift 2 ;;
            --ssl-cert) SSL_CERT_PATH="$2"; shift 2 ;;
            --ssl-key) SSL_KEY_PATH="$2"; shift 2 ;;
            --ssl-ca) SSL_CA_CERT_PATH="$2"; shift 2 ;;
            --dry-run) DRY_RUN="true"; shift ;;
            -h) show_usage; exit 0 ;;
            *) log_error "PARAM" "Unknown option: $1"; show_usage; exit 1 ;;
        esac
    done

    if [ -z "$IMAGE_PATH" ]; then
        log_error "PARAM" "Image path is required (-i)"
        show_usage
        exit 1
    fi

    if [ ! -f "$IMAGE_PATH" ]; then
        log_error "PARAM" "Image file not found: $IMAGE_PATH"
        exit 1
    fi

    # 如果指定了宿主机证书源路径，自动解析虚机内路径
    if [ -n "$SSL_CERT_SRC" ]; then
        SSL_CERT_PATH="$SSL_CERT_VM_DIR/$(basename "$SSL_CERT_SRC")"
    fi
    if [ -n "$SSL_KEY_SRC" ]; then
        SSL_KEY_PATH="$SSL_CERT_VM_DIR/$(basename "$SSL_KEY_SRC")"
    fi
    if [ -n "$SSL_CA_CERT_SRC" ]; then
        SSL_CA_CERT_PATH="$SSL_CERT_VM_DIR/$(basename "$SSL_CA_CERT_SRC")"
    fi

    # 验证宿主机证书文件存在
    if [ -n "$SSL_CERT_SRC" ] && [ ! -f "$SSL_CERT_SRC" ]; then
        log_error "PARAM" "SSL cert source file not found: $SSL_CERT_SRC"
        exit 1
    fi
    if [ -n "$SSL_KEY_SRC" ] && [ ! -f "$SSL_KEY_SRC" ]; then
        log_error "PARAM" "SSL key source file not found: $SSL_KEY_SRC"
        exit 1
    fi
    if [ -n "$SSL_CA_CERT_SRC" ] && [ ! -f "$SSL_CA_CERT_SRC" ]; then
        log_error "PARAM" "SSL CA cert source file not found: $SSL_CA_CERT_SRC"
        exit 1
    fi

    log_info "PARAM" "IMAGE_PATH=$IMAGE_PATH"
    log_info "PARAM" "INSTALL_DIR=$INSTALL_DIR"
    log_info "PARAM" "SSL_ENABLED=$SSL_ENABLED"
    if [ "$SSL_ENABLED" = "true" ]; then
        if [ -n "$SSL_CERT_SRC" ]; then
            log_info "PARAM" "SSL_CERT_SRC=$SSL_CERT_SRC -> VM:$SSL_CERT_PATH"
            log_info "PARAM" "SSL_KEY_SRC=$SSL_KEY_SRC -> VM:$SSL_KEY_PATH"
            log_info "PARAM" "SSL_CA_CERT_SRC=${SSL_CA_CERT_SRC:-<not set>} -> VM:${SSL_CA_CERT_PATH:-<not set>}"
            log_info "PARAM" "SSL_CERT_VM_DIR=$SSL_CERT_VM_DIR"
        else
            log_info "PARAM" "SSL_CERT_PATH=$SSL_CERT_PATH"
            log_info "PARAM" "SSL_KEY_PATH=$SSL_KEY_PATH"
            log_info "PARAM" "SSL_CA_CERT_PATH=${SSL_CA_CERT_PATH:-<not set>}"
        fi
    fi
    log_info "PARAM" "DRY_RUN=$DRY_RUN"
}

# ==============================================================================
# 步骤 1: 环境预检查
# ==============================================================================
step1_check_environment() {
    log_step "CHECK" "Step 1/5: Checking environment"
    start_timer "check"
    
    local check_pass=true
    
    # 检查 virt-customize
    if command -v virt-customize &>/dev/null; then
        local version
        version=$(virt-customize --version 2>/dev/null || echo "unknown")
        log_info "CHECK" "virt-customize found: $version [OK]"
    else
        log_error "CHECK" "virt-customize not found. Install: yum install libguestfs-tools"
        check_pass=false
    fi
    
    # 检查 qemu-img
    if command -v qemu-img &>/dev/null; then
        log_info "CHECK" "qemu-img found [OK]"
    else
        log_warn "CHECK" "qemu-img not found, image validation skipped"
    fi
    
    # 检查镜像文件格式
    if command -v qemu-img &>/dev/null; then
        local fmt
        fmt=$(qemu-img info --output=json "$IMAGE_PATH" | jq -r '.format')
        log_info "CHECK" "Image format: $fmt"
        if [[ "$fmt" != "qcow2" && "$fmt" != "raw" ]]; then
            log_warn "CHECK" "Image format '$fmt' may not be fully supported"
        fi
    fi
    
    # 检查镜像文件权限
    if [ -r "$IMAGE_PATH" ] && [ -w "$IMAGE_PATH" ]; then
        local size
        size=$(du -h "$IMAGE_PATH" | cut -f1)
        log_info "CHECK" "Image permissions: readable+writable [OK]"
        log_info "CHECK" "Image size: $size"
    else
        log_error "CHECK" "Image file not readable/writable: $IMAGE_PATH"
        check_pass=false
    fi
    
    # 检查 virtcca_deploy 源码目录
    if [ -d "$VIRTCCA_DEPLOY_DIR" ] && [ -d "$GUEST_AGENT_DIR" ]; then
        log_info "CHECK" "virtcca_deploy dir: $VIRTCCA_DEPLOY_DIR [OK]"
    else
        log_error "CHECK" "virtcca_deploy not found"
        check_pass=false
    fi
    
    # 检查 requirements.txt
    if [ -f "$GUEST_AGENT_DIR/requirements.txt" ]; then
        local dep_count
        dep_count=$(wc -l < "$GUEST_AGENT_DIR/requirements.txt")
        log_info "CHECK" "requirements.txt found: $dep_count dependencies [OK]"
    else
        log_warn "CHECK" "requirements.txt not found"
    fi
    
    # 检查 service 文件
    if [ -f "$GUEST_AGENT_DIR/virtcca-guest-agent.service" ]; then
        log_info "CHECK" "systemd service file found [OK]"
    else
        log_warn "CHECK" "virtcca-guest-agent.service not found, auto-start may not work"
    fi
    
    local elapsed
    elapsed=$(stop_timer "check")
    log_info "CHECK" "Environment check completed in ${elapsed}s"
    
    if [ "$check_pass" = false ]; then
        die "Environment check failed, aborting" "CHECK"
    fi
}

# ==============================================================================
# 步骤 2: 准备临时目录
# ==============================================================================
step2_prepare_temp() {
    log_step "TEMP" "Step 2/5: Preparing temporary directory"
    start_timer "temp"
    
    TEMP_DIR=$(mktemp -d /tmp/ga_inject_XXXXXX)
    log_info "TEMP" "Created temp directory: $TEMP_DIR"
    
    # 复制整个 virtcca_deploy 目录
    cp -r "$VIRTCCA_DEPLOY_DIR" "$TEMP_DIR/virtcca_deploy"
    local file_count
    file_count=$(find "$TEMP_DIR/virtcca_deploy" -type f | wc -l)
    log_info "TEMP" "Copied $file_count files from virtcca_deploy to temp directory"
    
    local elapsed
    elapsed=$(stop_timer "temp")
    log_info "TEMP" "Temp directory prepared in ${elapsed}s"
}

# ==============================================================================
# 步骤 3: 复制独立安装脚本
# ==============================================================================
step3_copy_setup_script() {
    log_step "COPY" "Step 3/5: Copying standalone setup script"
    start_timer "copy"

    local setup_src="$SCRIPTS_DIR/setup_vm.sh"

    if [ ! -f "$setup_src" ]; then
        log_error "COPY" "setup_vm.sh not found at: $setup_src"
        die "setup_vm.sh not found in guest_agent source directory" "COPY"
    fi

    cp "$setup_src" "$TEMP_DIR/setup_vm.sh"
    chmod +x "$TEMP_DIR/setup_vm.sh"

    log_info "COPY" "setup_vm.sh copied to temp directory"
    log_info "COPY" "Source: $setup_src"
    log_info "COPY" "Dest:   $TEMP_DIR/setup_vm.sh"

    local elapsed
    elapsed=$(stop_timer "copy")
    log_info "COPY" "Setup script copied in ${elapsed}s"
}

# ==============================================================================
# 步骤 4: 执行注入
# ==============================================================================
step4_inject() {
    log_step "INJECT" "Step 4/5: Injecting guest agent into VM image"
    start_timer "inject"
    
    log_info "INJECT" "Target image: $IMAGE_PATH"
    log_info "INJECT" "Install dir (VM): $INSTALL_DIR"
    log_info "INJECT" "Temp directory: $TEMP_DIR"
    
    # 准备 SSL 证书（从宿主机复制到临时目录）
    local has_certs=false
    if [ -n "$SSL_CERT_SRC" ] && [ -n "$SSL_KEY_SRC" ]; then
        mkdir -p "$TEMP_DIR/certs"
        cp "$SSL_CERT_SRC" "$TEMP_DIR/certs/"
        cp "$SSL_KEY_SRC" "$TEMP_DIR/certs/"
        if [ -n "$SSL_CA_CERT_SRC" ]; then
            cp "$SSL_CA_CERT_SRC" "$TEMP_DIR/certs/"
        fi
        has_certs=true
        log_info "INJECT" "SSL certs copied to temp directory: $TEMP_DIR/certs"
    fi

    # 准备 ifcfg-template 网络配置模板
    local conf_dir="$(cd "$(dirname "${BASH_SOURCE[0]}")/../conf" && pwd)"
    local has_ifcfg_template=false
    if [ -f "$conf_dir/ifcfg-template" ]; then
        mkdir -p "$TEMP_DIR/conf"
        cp "$conf_dir/ifcfg-template" "$TEMP_DIR/conf/"
        has_ifcfg_template=true
        log_info "INJECT" "ifcfg-template copied to temp directory: $TEMP_DIR/conf/"
    else
        log_warn "INJECT" "ifcfg-template not found in $conf_dir"
    fi

    # 打印手动执行的 virt-customize 命令
    echo ""
    echo -e "${CYAN}============================================================${NC}"
    echo -e "${CYAN}Manual virt-customize command (for verification):${NC}"
    echo -e "${CYAN}============================================================${NC}"
    echo ""
    echo "virt-customize -a \"$IMAGE_PATH\" \\"
    echo "  --run-command \"mkdir -p /tmp/ga_inject\" \\"
    echo "  --copy-in $TEMP_DIR/virtcca_deploy:/tmp/ga_inject/ \\"
    echo "  --copy-in $TEMP_DIR/setup_vm.sh:/tmp/ga_inject/"
    if [ "$has_certs" = true ]; then
        echo "  --copy-in $TEMP_DIR/certs/agent.crt:$SSL_CERT_VM_DIR/ \\"
        echo "  --copy-in $TEMP_DIR/certs/agent.key:$SSL_CERT_VM_DIR/ \\"
        echo "  --copy-in $TEMP_DIR/certs/ca.crt:$SSL_CERT_VM_DIR/ \\"
    fi
    if [ "$has_ifcfg_template" = true ]; then
        echo "  --copy-in $TEMP_DIR/conf/ifcfg-template:/etc/virtcca_deploy/ \\"
    fi
    echo "  --run-command \"chmod +x /tmp/ga_inject/setup_vm.sh\" \\"
    echo "  --run-command \"/tmp/ga_inject/setup_vm.sh \\\"$INSTALL_DIR\\\" \\\"$SSL_ENABLED\\\" \\\"$SSL_CERT_PATH\\\" \\\"$SSL_KEY_PATH\\\" \\\"$SSL_CA_CERT_PATH\\\"\" \\"
    echo "  --run-command \"rm -rf /tmp/ga_inject\""
    echo ""
    echo -e "${CYAN}============================================================${NC}"
    echo ""
    log_info "INJECT" "You can run the above command manually to verify the injection"
    
    if [ "$DRY_RUN" = "true" ]; then
        log_info "INJECT" "DRY RUN mode - skipping automatic injection"
        log_info "INJECT" "Temp files preserved at: $TEMP_DIR"
        log_info "INJECT" "Please run the virt-customize command above manually"
        return 0
    fi
    
    # 备份镜像修改时间
    local mtime_before
    mtime_before=$(stat -c %Y "$IMAGE_PATH" 2>/dev/null || echo "unknown")
    log_info "INJECT" "Image mtime before: $mtime_before"
    
    # 构建 virt-customize 命令
    local vc_cmd="virt-customize -a \"$IMAGE_PATH\""
    vc_cmd+=" --run-command \"mkdir -p /tmp/ga_inject\""
    vc_cmd+=" --copy-in \"$TEMP_DIR/virtcca_deploy:/tmp/ga_inject/\""
    vc_cmd+=" --copy-in \"$TEMP_DIR/setup_vm.sh:/tmp/ga_inject/\""
    if [ "$has_certs" = true ]; then
        vc_cmd+=" --run-command \"mkdir -p $SSL_CERT_VM_DIR\""
        vc_cmd+=" --copy-in \"$TEMP_DIR/certs/agent.crt:$SSL_CERT_VM_DIR/\""
        vc_cmd+=" --copy-in \"$TEMP_DIR/certs/agent.key:$SSL_CERT_VM_DIR/\""
        vc_cmd+=" --copy-in \"$TEMP_DIR/certs/ca.crt:$SSL_CERT_VM_DIR/\""
        log_info "INJECT" "SSL certs will be copied to VM: $SSL_CERT_VM_DIR"
    fi
    if [ "$has_ifcfg_template" = true ]; then
        vc_cmd+=" --run-command \"mkdir -p /etc/virtcca_deploy\""
        vc_cmd+=" --copy-in \"$TEMP_DIR/conf/ifcfg-template:/etc/virtcca_deploy/\""
        log_info "INJECT" "ifcfg-template will be copied to VM: /etc/virtcca_deploy/"
    fi
    vc_cmd+=" --run-command \"chmod +x /tmp/ga_inject/setup_vm.sh\""
    vc_cmd+=" --run-command \"/tmp/ga_inject/setup_vm.sh \\\"$INSTALL_DIR\\\" \\\"$SSL_ENABLED\\\" \\\"$SSL_CERT_PATH\\\" \\\"$SSL_KEY_PATH\\\" \\\"$SSL_CA_CERT_PATH\\\"\""
    vc_cmd+=" --run-command \"sed -i 's/^#*PermitRootLogin.*/PermitRootLogin no/' /etc/ssh/sshd_config\""
    vc_cmd+=" --run-command \"rm -rf /tmp/ga_inject\""
    
    # 执行注入
    log_info "INJECT" "Running virt-customize..."
    eval $vc_cmd 2>&1 | tee -a "$LOG_FILE"

    local inject_rc=${PIPESTATUS[0]}
    
    if [ $inject_rc -eq 0 ]; then
        log_info "INJECT" "virt-customize completed successfully"
    else
        log_error "INJECT" "virt-customize failed with exit code: $inject_rc"
        log_info "INJECT" "Temp files preserved at: $TEMP_DIR"
        log_info "INJECT" "You can retry with the manual command above"
        die "virt-customize injection failed" "INJECT"
    fi
    
    # 检查镜像是否被修改
    local mtime_after
    mtime_after=$(stat -c %Y "$IMAGE_PATH" 2>/dev/null || echo "unknown")
    log_info "INJECT" "Image mtime after: $mtime_after"
    
    if [ "$mtime_before" != "$mtime_after" ] && [ "$mtime_before" != "unknown" ]; then
        log_info "INJECT" "Image file was modified (confirmed)"
    else
        log_warn "INJECT" "Image file timestamp unchanged - verify injection result"
    fi
    
    local elapsed
    elapsed=$(stop_timer "inject")
    log_info "INJECT" "Injection completed in ${elapsed}s"
}

# ==============================================================================
# 步骤 5: 清理临时目录
# ==============================================================================
step5_cleanup() {
    log_step "CLEANUP" "Step 5/5: Cleanup"
    start_timer "cleanup"
    
    local end_time
    end_time=$(date +%s)
    local total_time=$((end_time - START_TIME))
    local end_time_human
    end_time_human=$(date '+%Y-%m-%d %H:%M:%S')
    
    # 清理临时目录
    if [ -n "$TEMP_DIR" ] && [ "$KEEP_TEMP" = "false" ]; then
        if [ -d "$TEMP_DIR" ]; then
            rm -rf "$TEMP_DIR"
            log_info "CLEANUP" "Temp directory removed: $TEMP_DIR"
        fi
    elif [ "$KEEP_TEMP" = "true" ] && [ -n "$TEMP_DIR" ]; then
        log_info "CLEANUP" "Temp directory preserved: $TEMP_DIR"
        log_info "CLEANUP" "Contents:"
        find "$TEMP_DIR" -type f | while read -r f; do
            log_info "CLEANUP" "  $f"
        done
    fi

    log_info "CLEANUP" "Full log saved to: $LOG_FILE"
    
    local elapsed
    elapsed=$(stop_timer "cleanup")
    log_info "CLEANUP" "Cleanup completed in ${elapsed}s"
    
    # 打印报告摘要
    echo ""
    echo -e "${BLUE}================================================================================${NC}"
    echo -e "${GREEN}  Guest Agent Injection Completed Successfully${NC}"
    echo -e "${BLUE}================================================================================${NC}"
    echo -e "  Duration:    ${total_time}s"
    echo -e "  Warnings:    $WARN_COUNT"
    echo -e "  Errors:      $ERROR_COUNT"
    echo -e "  Log File:    $LOG_FILE"
    echo -e "${BLUE}================================================================================${NC}"
}


# ==============================================================================
# 错误处理
# ==============================================================================
error_handler() {
    local line_no="$1"
    local error_code="$2"
    log_error "FATAL" "Error on line $line_no: exit code $error_code"
    log_error "FATAL" "Temp directory: ${TEMP_DIR:-<not created>}"
    log_error "FATAL" "Log file: $LOG_FILE"
    exit "$error_code"
}

trap 'error_handler ${LINENO} $?' ERR

# ==============================================================================
# 主函数
# ==============================================================================
main() {
    # 初始化日志
    echo "" > "$LOG_FILE"
    log_info "MAIN" "=========================================="
    log_info "MAIN" "Guest Agent Injection Tool Starting"
    log_info "MAIN" "=========================================="
    log_info "MAIN" "Start time: $START_TIME_HUMAN"
    log_info "MAIN" "Process ID: $SCRIPT_PID"
    log_info "MAIN" "Log file: $LOG_FILE"
    
    parse_args "$@"
    
    if [ "$DRY_RUN" = "true" ]; then
        log_info "MAIN" "DRY RUN mode enabled - no changes will be made"
    fi
    
    step1_check_environment
    step2_prepare_temp
    step3_copy_setup_script
    step4_inject
    step5_cleanup
    
    log_info "MAIN" "All steps completed successfully"
}

main "$@"