#!/bin/bash

# ===========================================
# 学生状态变更处理脚本控制程序 - 生产环境版本
# 用于启动、停止、重启处理脚本 (Ubuntu兼容性修复版本)
# ===========================================
#
# 生产环境部署指南:
# 1. 确保所有修复版本脚本存在:
#    - process_student_changes_fixed.sh (状态变更处理)
#    - process_student_resume_fixed.sh  (复学处理)
#
# 2. 确保配置文件存在:
#    - data.conf (数据库配置和脚本参数)
#
# 3. 启动所有服务:
#    ./control_scripts.sh startall
#
# 4. 监控运行状态:
#    ./control_scripts.sh statusall
#
# 5. 健康检查:
#    ./control_scripts.sh health all
#
# 6. 查看系统资源:
#    ./control_scripts.sh info
#
# 日志文件位置:
# - 控制脚本日志: logs/control_scripts_YYYYMMDD.log
# - 处理脚本日志: student_status_change/process_student_*_YYYYMMDD_HHMMSS.log

# Disable strict error checking for better production resilience
# set -euo pipefail  # Temporarily disabled for production robustness

# Force C locale for consistent behavior across systems
export LANG=C
export LC_ALL=C

# Load configuration
SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
CONFIG_FILE="${SCRIPT_DIR}/data.conf"

if [[ ! -f "$CONFIG_FILE" ]]; then
    echo "错误：配置文件 $CONFIG_FILE 未找到！"
    echo "请确保 data.conf 文件存在于脚本目录中"
    exit 1
fi

source "$CONFIG_FILE"

# Production environment setup
PRODUCTION_LOG_DIR="${SCRIPT_DIR}/logs"
mkdir -p "$PRODUCTION_LOG_DIR"
PRODUCTION_LOG_FILE="${PRODUCTION_LOG_DIR}/control_scripts_$(date +%Y%m%d).log"

# Script definitions - Production versions with Ubuntu compatibility fixes
# Using indexed arrays for better bash compatibility
SCRIPT_NAMES=("changes" "resume")
SCRIPT_FILES=("process_student_changes_fixed.sh" "process_student_resume_fixed.sh")

# Function to get script file by name
get_script_file() {
    local script_name="$1"
    for i in "${!SCRIPT_NAMES[@]}"; do
        if [[ "${SCRIPT_NAMES[$i]}" == "$script_name" ]]; then
            echo "${SCRIPT_FILES[$i]}"
            return 0
        fi
    done
    return 1
}

# PID files
PID_DIR="${SCRIPT_DIR}/pids"
mkdir -p "$PID_DIR"

# Functions
log() {
    local level="$1"
    local message="$2"
    local timestamp=$(date '+%Y-%m-%d %H:%M:%S')
    local log_message="[$timestamp] [$level] $message"

    # Output to console
    echo "$log_message"

    # Output to production log file
    echo "$log_message" >> "$PRODUCTION_LOG_FILE"
}

get_pid_file() {
    local script_name="$1"
    echo "${PID_DIR}/${script_name}.pid"
}

get_lock_file() {
    local script_name="$1"
    echo "${SCRIPT_DIR}/${script_name}.lock"
}

is_running() {
    local script_name="$1"
    local pid_file=$(get_pid_file "$script_name")
    local lock_file=$(get_lock_file "$script_name")

    # Check PID file
    if [[ -f "$pid_file" ]]; then
        local pid=$(cat "$pid_file")
        if kill -0 "$pid" 2>/dev/null; then
            return 0  # Running
        else
            log "WARN" "删除脚本 $script_name 的过期PID文件"
            rm -f "$pid_file"
        fi
    fi

    # Check lock file
    if [[ -f "$lock_file" ]]; then
        local lock_pid=$(cat "$lock_file")
        if kill -0 "$lock_pid" 2>/dev/null; then
            return 0  # Running
        else
            log "WARN" "删除脚本 $script_name 的过期锁定文件"
            rm -f "$lock_file"
        fi
    fi

    return 1  # Not running
}

# Health check function for production monitoring
health_check() {
    local script_name="$1"
    local script_file="${SCRIPT_DIR}/$(get_script_file "$script_name")"

    log "INFO" "执行 $script_name 的健康检查..."

    # Check if script file exists and is executable
    if [[ ! -f "$script_file" ]]; then
        log "ERROR" "$script_name 脚本文件不存在: $script_file"
        return 1
    fi

    if [[ ! -x "$script_file" ]]; then
        log "WARN" "$script_name 脚本文件没有执行权限，正在修复..."
        chmod +x "$script_file"
    fi

    # Check database connectivity
    if ! mysql -h"$DB_HOST" -P"$DB_PORT" -u"$DB_USER" -p"$DB_PASS" "$DB_NAME" -e "SELECT 1;" >/dev/null 2>&1; then
        log "ERROR" "$script_name 数据库连接失败"
        return 1
    fi

    # Check if script is running
    if ! is_running "$script_name"; then
        log "WARN" "$script_name 脚本未运行"
        return 1
    fi

    log "INFO" "$script_name 健康检查通过"
    return 0
}

# Get system resource usage
get_system_info() {
    log "INFO" "=== 系统资源信息 ==="

    # CPU usage
    local cpu_usage=$(top -bn1 | grep "Cpu(s)" | sed "s/.*, *\([0-9.]*\)%* id.*/\1/" | awk '{print 100 - $1}')
    log "INFO" "CPU使用率: ${cpu_usage}%"

    # Memory usage
    local mem_info=$(free -h | grep "^Mem:")
    log "INFO" "内存信息: $mem_info"

    # Disk usage
    local disk_info=$(df -h "$SCRIPT_DIR" | tail -1 | awk '{print $1 ": " $5 " used (" $4 " free)"}')
    log "INFO" "磁盘使用: $disk_info"

    # Process count
    local process_count=$(pgrep -f "process_student.*\.sh" | wc -l)
    log "INFO" "运行中的学生处理进程数: $process_count"
}

start_script() {
    local script_name="$1"
    local script_file="${SCRIPT_DIR}/$(get_script_file "$script_name")"
    local pid_file=$(get_pid_file "$script_name")

    if [[ ! -f "$script_file" ]]; then
        log "ERROR" "脚本文件未找到: $script_file"
        return 1
    fi

    if is_running "$script_name"; then
        log "INFO" "$script_name 已在运行"
        return 0
    fi

    log "INFO" "正在启动 $script_name..."
    chmod +x "$script_file"

    # Start script in background
    nohup "$script_file" > /dev/null 2>&1 &
    local pid=$!

    # Wait a moment for script to start
    sleep 2

    if kill -0 "$pid" 2>/dev/null; then
        echo $pid > "$pid_file"
        log "INFO" "$script_name 启动成功 (PID: $pid)"
        return 0
    else
        log "ERROR" "$script_name 启动失败"
        return 1
    fi
}

stop_script() {
    local script_name="$1"
    local pid_file=$(get_pid_file "$script_name")
    local lock_file=$(get_lock_file "$script_name")
    local stopped=false

    log "INFO" "正在停止 $script_name..."

    # 尝试通过PID文件停止
    if [[ -f "$pid_file" ]]; then
        local pid=$(cat "$pid_file")
        if kill -0 "$pid" 2>/dev/null; then
            kill "$pid"
            sleep 2
            if ! kill -0 "$pid" 2>/dev/null; then
                log "INFO" "$script_name 停止成功 (PID: $pid)"
                stopped=true
            fi
        fi
        rm -f "$pid_file"
    fi

    # 尝试通过锁定文件停止
    if [[ -f "$lock_file" ]]; then
        local lock_pid=$(cat "$lock_file")
        if kill -0 "$lock_pid" 2>/dev/null; then
            kill "$lock_pid"
            sleep 2
            if ! kill -0 "$lock_pid" 2>/dev/null; then
                log "INFO" "$script_name 停止成功 (PID: $lock_pid)"
                stopped=true
            fi
        fi
        rm -f "$lock_file"
    fi

    if [[ "$stopped" == false ]]; then
        log "WARN" "$script_name 可能未运行或优雅停止失败"
    fi
}

restart_script() {
    local script_name="$1"
    log "INFO" "正在重启 $script_name..."
    stop_script "$script_name"
    sleep 3
    start_script "$script_name"
}

status_script() {
    local script_name="$1"
    if is_running "$script_name"; then
        local pid_file=$(get_pid_file "$script_name")
        local lock_file=$(get_lock_file "$script_name")

        if [[ -f "$pid_file" ]]; then
            local pid=$(cat "$pid_file")
            log "INFO" "$script_name 正在运行 (PID: $pid)"
        elif [[ -f "$lock_file" ]]; then
            local lock_pid=$(cat "$lock_file")
            log "INFO" "$script_name 正在运行 (PID: $lock_pid)"
        else
            log "INFO" "$script_name 状态未知"
        fi
    else
        log "INFO" "$script_name 未运行"
    fi
}

show_usage() {
    cat << EOF
用法: $0 <命令> <脚本名称>

命令:
    start    启动指定的脚本
    stop     停止指定的脚本
    restart  重启指定的脚本
    status   显示指定脚本的状态
    health   执行脚本健康检查
    startall 启动所有脚本
    stopall  停止所有脚本
    statusall 显示所有脚本的状态
    info     显示系统资源信息

脚本名称:
    changes  学生状态变更脚本 (休学/退学/毕业) - Ubuntu兼容修复版本
    resume   学生复学脚本 (复学) - Ubuntu兼容修复版本
    all      所有脚本

生产环境示例:
    $0 startall           # 启动所有学生处理脚本
    $0 statusall          # 检查所有脚本运行状态
    $0 health all         # 执行所有脚本的健康检查
    $0 info               # 查看系统资源使用情况
    $0 restart changes    # 重启状态变更处理脚本
    $0 stopall            # 停止所有处理脚本

传统示例:
    $0 start changes      # 启动状态变更处理脚本
    $0 stop resume        # 停止复学处理脚本
    $0 status changes     # 显示状态变更脚本状态

注意:
    本脚本使用修复版本，已适配Ubuntu环境，解决了循环处理和数据库查询的兼容性问题

EOF
}

# Production environment initialization
init_production_env() {
    log "INFO" "初始化生产环境..."

    # Check script files exist
    for script_name in "${!SCRIPTS[@]}"; do
        local script_file="${SCRIPT_DIR}/${SCRIPTS[$script_name]}"
        if [[ ! -f "$script_file" ]]; then
            log "ERROR" "脚本文件不存在: $script_file"
            log "ERROR" "请确保已部署修复版本的脚本文件"
            exit 1
        fi
    done

    # Test database connectivity
    if ! mysql -h"$DB_HOST" -P"$DB_PORT" -u"$DB_USER" -p"$DB_PASS" "$DB_NAME" -e "SELECT 1;" >/dev/null 2>&1; then
        log "ERROR" "数据库连接失败，请检查配置"
        exit 1
    fi

    log "INFO" "生产环境初始化完成"
}

# Main function
main() {
    # Initialize production environment
    init_production_env

    local command="${1:-}"
    local script_name="${2:-}"

    case "$command" in
        start)
            if [[ "$script_name" == "all" ]]; then
                for script in "${SCRIPT_NAMES[@]}"; do
                    start_script "$script"
                done
            elif get_script_file "$script_name" >/dev/null 2>&1; then
                start_script "$script_name"
            else
                log "ERROR" "未知的脚本名称: $script_name"
                show_usage
                exit 1
            fi
            ;;

        stop)
            if [[ "$script_name" == "all" ]]; then
                for script in "${SCRIPT_NAMES[@]}"; do
                    stop_script "$script"
                done
            elif get_script_file "$script_name" >/dev/null 2>&1; then
                stop_script "$script_name"
            else
                log "ERROR" "未知的脚本名称: $script_name"
                show_usage
                exit 1
            fi
            ;;

        restart)
            if [[ "$script_name" == "all" ]]; then
                for script in "${SCRIPT_NAMES[@]}"; do
                    restart_script "$script"
                done
            elif get_script_file "$script_name" >/dev/null 2>&1; then
                restart_script "$script_name"
            else
                log "ERROR" "未知的脚本名称: $script_name"
                show_usage
                exit 1
            fi
            ;;

        status)
            if [[ "$script_name" == "all" ]]; then
                for script in "${SCRIPT_NAMES[@]}"; do
                    status_script "$script"
                done
            elif get_script_file "$script_name" >/dev/null 2>&1; then
                status_script "$script_name"
            else
                log "ERROR" "未知的脚本名称: $script_name"
                show_usage
                exit 1
            fi
            ;;

        startall)
            log "INFO" "正在启动所有脚本..."
            for script in "${SCRIPT_NAMES[@]}"; do
                start_script "$script"
            done
            ;;

        stopall)
            log "INFO" "正在停止所有脚本..."
            for script in "${SCRIPT_NAMES[@]}"; do
                stop_script "$script"
            done
            ;;

        statusall)
            log "INFO" "正在检查所有脚本的状态..."
            for script in "${SCRIPT_NAMES[@]}"; do
                status_script "$script"
            done
            ;;

        health)
            if [[ "$script_name" == "all" ]]; then
                local all_healthy=true
                for script in "${SCRIPT_NAMES[@]}"; do
                    if ! health_check "$script"; then
                        all_healthy=false
                    fi
                done
                if [[ "$all_healthy" == true ]]; then
                    log "INFO" "所有脚本健康检查通过"
                    exit 0
                else
                    log "ERROR" "部分脚本健康检查失败"
                    exit 1
                fi
            elif get_script_file "$script_name" >/dev/null 2>&1; then
                if health_check "$script_name"; then
                    log "INFO" "$script_name 健康检查通过"
                    exit 0
                else
                    log "ERROR" "$script_name 健康检查失败"
                    exit 1
                fi
            else
                log "ERROR" "未知的脚本名称: $script_name"
                show_usage
                exit 1
            fi
            ;;

        info)
            get_system_info
            ;;

        *)
            log "ERROR" "未知命令: $command"
            show_usage
            exit 1
            ;;
    esac
}

# Run main function
main "$@"