#!/bin/bash
# KVM Manager 一键启动脚本
# 用法: ./start.sh [start|stop|restart|status]
set -e

# ── 配置 ──────────────────────────────────────────────
SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
BACKEND_DIR="$SCRIPT_DIR/backend"
FRONTEND_DIR="$SCRIPT_DIR/frontend"
LOG_DIR="$SCRIPT_DIR/logs"
PID_DIR="$SCRIPT_DIR/.pid"

BACKEND_PORT=8004
FRONTEND_PORT=8006
BACKEND_CMD="$BACKEND_DIR/venv/bin/python -m uvicorn app.main:app --host 0.0.0.0 --port $BACKEND_PORT"
FRONTEND_CMD="$BACKEND_DIR/venv/bin/python $FRONTEND_DIR/serve.py"

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

# ── 工具函数 ──────────────────────────────────────────
info()  { echo -e "${CYAN}[INFO]${NC} $1"; }
ok()    { echo -e "${GREEN}[OK]${NC} $1"; }
warn()  { echo -e "${YELLOW}[WARN]${NC} $1"; }
fail()  { echo -e "${RED}[FAIL]${NC} $1"; }

mkdir -p "$LOG_DIR" "$PID_DIR"

# 检查端口是否被占用，返回 PID
port_pid() {
    lsof -ti:$1 2>/dev/null | head -1
}

# 等待端口可用
wait_port() {
    local port=$1 name=$2 max=10 count=0
    while [ $count -lt $max ]; do
        if port_pid $port >/dev/null 2>&1; then
            return 0
        fi
        sleep 1
        count=$((count + 1))
    done
    return 1
}

# ── 启动后端 ──────────────────────────────────────────
start_backend() {
    info "启动后端服务 (端口 $BACKEND_PORT)..."

    # 检查是否已运行
    local existing_pid=$(port_pid $BACKEND_PORT)
    if [ -n "$existing_pid" ]; then
        warn "后端已在运行 (PID: $existing_pid)"
        return 0
    fi

    # 检查 venv
    if [ ! -d "$BACKEND_DIR/venv" ]; then
        fail "未找到 Python 虚拟环境，请先运行: cd backend && python3 -m venv venv && source venv/bin/activate && pip install -r requirements.txt"
        return 1
    fi

    # 检查 libvirtd
    if ! systemctl is-active --quiet libvirtd 2>/dev/null; then
        warn "libvirtd 未运行，尝试启动..."
        systemctl start libvirtd 2>/dev/null || warn "libvirtd 启动失败，后端可能无法连接虚拟机"
    fi

    cd "$BACKEND_DIR"
    nohup $BACKEND_CMD > "$LOG_DIR/backend.log" 2>&1 &
    local pid=$!
    echo $pid > "$PID_DIR/backend.pid"

    sleep 2
    if port_pid $BACKEND_PORT >/dev/null 2>&1; then
        ok "后端服务已启动 (PID: $pid, 端口: $BACKEND_PORT)"
        ok "日志: $LOG_DIR/backend.log"
    else
        fail "后端服务启动失败，查看日志:"
        tail -20 "$LOG_DIR/backend.log"
        return 1
    fi
}

# ── 启动前端 ──────────────────────────────────────────
start_frontend() {
    info "启动前端服务 (端口 $FRONTEND_PORT)..."

    local existing_pid=$(port_pid $FRONTEND_PORT)
    if [ -n "$existing_pid" ]; then
        warn "前端已在运行 (PID: $existing_pid)"
        return 0
    fi

    # 检查 dist
    if [ ! -d "$FRONTEND_DIR/dist" ]; then
        warn "未找到前端构建产物，正在构建..."
        cd "$FRONTEND_DIR"
        npm install --silent && npm run build
        if [ ! -d "$FRONTEND_DIR/dist" ]; then
            fail "前端构建失败"
            return 1
        fi
        ok "前端构建完成"
    fi

    cd "$FRONTEND_DIR"
    nohup $FRONTEND_CMD > "$LOG_DIR/frontend.log" 2>&1 &
    local pid=$!
    echo $pid > "$PID_DIR/frontend.pid"

    sleep 2
    if port_pid $FRONTEND_PORT >/dev/null 2>&1; then
        ok "前端服务已启动 (PID: $pid, 端口: $FRONTEND_PORT)"
        ok "日志: $LOG_DIR/frontend.log"
    else
        fail "前端服务启动失败，查看日志:"
        tail -20 "$LOG_DIR/frontend.log"
        return 1
    fi
}

# ── 停止服务 ──────────────────────────────────────────
stop_service() {
    local name=$1 port=$2 pidfile=$PID_DIR/$3.pid
    info "停止 $name (端口 $port)..."

    # 先尝试 PID 文件
    if [ -f "$pidfile" ]; then
        local pid=$(cat "$pidfile")
        if ps -p "$pid" >/dev/null 2>&1; then
            kill "$pid" 2>/dev/null && ok "$name 已停止 (PID: $pid)" || warn "$name 停止失败"
        fi
        rm -f "$pidfile"
    fi

    # 再检查端口残留
    local residual=$(port_pid $port)
    if [ -n "$residual" ]; then
        kill "$residual" 2>/dev/null && ok "$name 残留进程已清理 (PID: $residual)" || true
    fi
}

stop_all() {
    info "停止所有服务..."
    stop_service "后端" $BACKEND_PORT "backend"
    stop_service "前端" $FRONTEND_PORT "frontend"
    ok "所有服务已停止"
}

# ── 状态 ──────────────────────────────────────────────
show_status() {
    echo ""
    echo -e "${CYAN}========================================${NC}"
    echo -e "${CYAN}    KVM Manager 服务状态${NC}"
    echo -e "${CYAN}========================================${NC}"

    # 后端
    local bpid=$(port_pid $BACKEND_PORT)
    if [ -n "$bpid" ]; then
        echo -e "  后端:  ${GREEN}● 运行中${NC}  PID: $bpid  端口: $BACKEND_PORT"
    else
        echo -e "  后端:  ${RED}○ 未运行${NC}"
    fi

    # 前端
    local fpid=$(port_pid $FRONTEND_PORT)
    if [ -n "$fpid" ]; then
        echo -e "  前端:  ${GREEN}● 运行中${NC}  PID: $fpid  端口: $FRONTEND_PORT"
    else
        echo -e "  前端:  ${RED}○ 未运行${NC}"
    fi

    echo ""
    echo -e "  访问地址: ${YELLOW}http://localhost:$FRONTEND_PORT${NC}"
    echo -e "  API文档:  ${YELLOW}http://localhost:$BACKEND_PORT/docs${NC}"
    echo -e "  日志目录: ${YELLOW}$LOG_DIR${NC}"
    echo ""
}

# ── 查看日志 ──────────────────────────────────────────
show_logs() {
    local target=${1:-all}
    case $target in
        backend|b)  tail -f "$LOG_DIR/backend.log" 2>/dev/null || fail "后端日志不存在" ;;
        frontend|f) tail -f "$LOG_DIR/frontend.log" 2>/dev/null || fail "前端日志不存在" ;;
        *)          tail -f "$LOG_DIR/backend.log" "$LOG_DIR/frontend.log" 2>/dev/null || fail "日志不存在" ;;
    esac
}

# ── 主入口 ────────────────────────────────────────────
usage() {
    echo ""
    echo -e "${CYAN}KVM Manager 一键启动脚本${NC}"
    echo ""
    echo "用法: $0 <命令>"
    echo ""
    echo "命令:"
    echo "  start    启动所有服务 (默认)"
    echo "  stop     停止所有服务"
    echo "  restart  重启所有服务"
    echo "  status   查看服务状态"
    echo "  logs     查看日志 (logs backend/frontend)"
    echo ""
    echo "示例:"
    echo "  $0              # 启动所有"
    echo "  $0 start        # 启动所有"
    echo "  $0 stop         # 停止所有"
    echo "  $0 restart      # 重启所有"
    echo "  $0 status       # 查看状态"
    echo "  $0 logs backend # 查看后端日志"
    echo ""
}

case "${1:-start}" in
    start)
        start_backend
        start_frontend
        show_status
        ;;
    stop)
        stop_all
        ;;
    restart)
        stop_all
        sleep 1
        start_backend
        start_frontend
        show_status
        ;;
    status)
        show_status
        ;;
    logs)
        show_logs "${2:-all}"
        ;;
    -h|--help|help)
        usage
        ;;
    *)
        usage
        exit 1
        ;;
esac