#!/bin/bash

# ========================================
# Go 服务管理脚本
# 用途：启动、停止、重启、查看状态
# ========================================

set -e

# 颜色定义
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
BLUE='\033[0;34m'
NC='\033[0m' # No Color

# 配置
SERVICE_DIR="/www/wwwroot/api.yunzer.cn"
LOG_FILE="$SERVICE_DIR/go.log"
PID_FILE="$SERVICE_DIR/go.pid"
MAIN_FILE="$SERVICE_DIR/main.go"

# 检查服务目录
if [ ! -d "$SERVICE_DIR" ]; then
    echo -e "${RED}错误：服务目录不存在: $SERVICE_DIR${NC}"
    exit 1
fi

# 检查 main.go
if [ ! -f "$MAIN_FILE" ]; then
    echo -e "${RED}错误：找不到 main.go: $MAIN_FILE${NC}"
    exit 1
fi

# 获取进程 ID
get_pid() {
    if [ -f "$PID_FILE" ]; then
        cat "$PID_FILE"
    else
        # 通过进程名查找
        pgrep -f "go run main.go" | head -n 1
    fi
}

# 检查服务是否运行
is_running() {
    local pid=$(get_pid)
    if [ -n "$pid" ] && kill -0 "$pid" 2>/dev/null; then
        return 0
    else
        return 1
    fi
}

# 启动服务
start() {
    echo -e "${BLUE}========================================${NC}"
    echo -e "${BLUE}启动 Go 服务${NC}"
    echo -e "${BLUE}========================================${NC}"
    echo ""
    
    if is_running; then
        local pid=$(get_pid)
        echo -e "${YELLOW}服务已在运行中 (PID: $pid)${NC}"
        return 0
    fi
    
    echo -e "${YELLOW}切换到服务目录...${NC}"
    cd "$SERVICE_DIR"
    
    echo -e "${YELLOW}启动服务...${NC}"
    nohup go run main.go > "$LOG_FILE" 2>&1 &
    local pid=$!
    echo $pid > "$PID_FILE"
    
    # 等待服务启动
    sleep 2
    
    if is_running; then
        echo -e "${GREEN}✓ 服务启动成功 (PID: $pid)${NC}"
        echo -e "${GREEN}✓ 日志文件: $LOG_FILE${NC}"
        echo ""
        echo -e "${YELLOW}查看日志：${NC}"
        echo -e "  tail -f $LOG_FILE"
        echo ""
        echo -e "${YELLOW}查看最近日志：${NC}"
        tail -n 20 "$LOG_FILE"
    else
        echo -e "${RED}✗ 服务启动失败${NC}"
        if [ -f "$LOG_FILE" ]; then
            echo -e "${YELLOW}最近的错误日志：${NC}"
            tail -n 20 "$LOG_FILE"
        fi
        exit 1
    fi
}

# 停止服务
stop() {
    echo -e "${BLUE}========================================${NC}"
    echo -e "${BLUE}停止 Go 服务${NC}"
    echo -e "${BLUE}========================================${NC}"
    echo ""
    
    if ! is_running; then
        echo -e "${YELLOW}服务未运行${NC}"
        rm -f "$PID_FILE"
        return 0
    fi
    
    local pid=$(get_pid)
    echo -e "${YELLOW}停止服务 (PID: $pid)...${NC}"
    
    # 尝试优雅停止
    kill "$pid" 2>/dev/null || true
    
    # 等待最多 10 秒
    local count=0
    while is_running && [ $count -lt 10 ]; do
        sleep 1
        count=$((count + 1))
        echo -n "."
    done
    echo ""
    
    # 如果还在运行，强制停止
    if is_running; then
        echo -e "${YELLOW}强制停止服务...${NC}"
        kill -9 "$pid" 2>/dev/null || true
        sleep 1
    fi
    
    # 清理所有相关进程
    pkill -f "go run main.go" 2>/dev/null || true
    
    rm -f "$PID_FILE"
    
    if is_running; then
        echo -e "${RED}✗ 服务停止失败${NC}"
        exit 1
    else
        echo -e "${GREEN}✓ 服务已停止${NC}"
    fi
}

# 重启服务
restart() {
    echo -e "${BLUE}========================================${NC}"
    echo -e "${BLUE}重启 Go 服务${NC}"
    echo -e "${BLUE}========================================${NC}"
    echo ""
    
    stop
    echo ""
    sleep 2
    start
}

# 查看状态
status() {
    echo -e "${BLUE}========================================${NC}"
    echo -e "${BLUE}Go 服务状态${NC}"
    echo -e "${BLUE}========================================${NC}"
    echo ""
    
    if is_running; then
        local pid=$(get_pid)
        echo -e "${GREEN}✓ 服务运行中${NC}"
        echo -e "  PID: $pid"
        echo -e "  目录: $SERVICE_DIR"
        echo -e "  日志: $LOG_FILE"
        echo ""
        
        # 显示进程信息
        echo -e "${YELLOW}进程信息：${NC}"
        ps aux | grep "$pid" | grep -v grep
        echo ""
        
        # 显示端口监听
        echo -e "${YELLOW}端口监听：${NC}"
        netstat -tlnp 2>/dev/null | grep "$pid" || lsof -i -P -n | grep "$pid" || echo "  无法获取端口信息"
        echo ""
        
        # 显示最近日志
        if [ -f "$LOG_FILE" ]; then
            echo -e "${YELLOW}最近日志（最后 10 行）：${NC}"
            tail -n 10 "$LOG_FILE"
        fi
    else
        echo -e "${RED}✗ 服务未运行${NC}"
        
        # 检查是否有残留进程
        local pids=$(pgrep -f "go run main.go" || true)
        if [ -n "$pids" ]; then
            echo -e "${YELLOW}发现残留进程：${NC}"
            ps aux | grep "go run main.go" | grep -v grep
            echo ""
            echo -e "${YELLOW}清理残留进程：${NC}"
            echo "  bash $0 stop"
        fi
        
        # 显示最近日志
        if [ -f "$LOG_FILE" ]; then
            echo ""
            echo -e "${YELLOW}最近日志（最后 20 行）：${NC}"
            tail -n 20 "$LOG_FILE"
        fi
    fi
}

# 查看日志
logs() {
    if [ ! -f "$LOG_FILE" ]; then
        echo -e "${RED}日志文件不存在: $LOG_FILE${NC}"
        exit 1
    fi
    
    if [ "$1" = "-f" ] || [ "$1" = "--follow" ]; then
        echo -e "${YELLOW}实时查看日志（Ctrl+C 退出）：${NC}"
        tail -f "$LOG_FILE"
    else
        local lines=${1:-50}
        echo -e "${YELLOW}最近 $lines 行日志：${NC}"
        tail -n "$lines" "$LOG_FILE"
    fi
}

# 显示帮助
help() {
    echo -e "${BLUE}========================================${NC}"
    echo -e "${BLUE}Go 服务管理脚本${NC}"
    echo -e "${BLUE}========================================${NC}"
    echo ""
    echo "用法: $0 {start|stop|restart|status|logs}"
    echo ""
    echo "命令："
    echo "  start    - 启动服务"
    echo "  stop     - 停止服务"
    echo "  restart  - 重启服务"
    echo "  status   - 查看服务状态"
    echo "  logs     - 查看日志（默认最后 50 行）"
    echo "  logs -f  - 实时查看日志"
    echo "  logs 100 - 查看最后 100 行日志"
    echo ""
    echo "示例："
    echo "  $0 start          # 启动服务"
    echo "  $0 restart        # 重启服务"
    echo "  $0 status         # 查看状态"
    echo "  $0 logs -f        # 实时查看日志"
    echo "  $0 logs 100       # 查看最后 100 行"
    echo ""
}

# 主函数
main() {
    case "${1:-}" in
        start)
            start
            ;;
        stop)
            stop
            ;;
        restart)
            restart
            ;;
        status)
            status
            ;;
        logs)
            logs "${2:-}"
            ;;
        help|--help|-h)
            help
            ;;
        *)
            echo -e "${RED}错误：未知命令 '$1'${NC}"
            echo ""
            help
            exit 1
            ;;
    esac
}

# 运行主函数
main "$@"