#!/bin/bash
# FlowStack 发布系统启动脚本
# 一键构建并启动前后端（前端产物嵌入 Go 单二进制，一个端口同时服务 API 与页面）
# 用法: ./run.sh [start|stop|restart|build|dev|backend|status|help]

set -e

# ============================================================
# 配置区
# ============================================================
PROJECT_NAME="FlowStack"
BACKEND_DIR="backend"
FRONTEND_DIR="frontend"
STANDALONE_BIN="flowstack"
STANDALONE_PORT="${PORT:-9527}"
FRONTEND_DEV_PORT=5173
STANDALONE_PID_FILE="$PWD/.flowstack.pid"
STANDALONE_LOG_FILE="$PWD/logs/flowstack.log"
BACKEND_DEV_PID_FILE="$PWD/.backend-dev.pid"

# ============================================================
# 通用函数
# ============================================================
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
BLUE='\033[0;34m'
NC='\033[0m'

info()    { echo -e "${BLUE}[INFO]${NC} $1"; }
success() { echo -e "${GREEN}[SUCCESS]${NC} $1"; }
warning() { echo -e "${YELLOW}[WARNING]${NC} $1"; }
error()   { echo -e "${RED}[ERROR]${NC} $1"; }

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
cd "$SCRIPT_DIR"

check_port() { lsof -ti:$1 2>/dev/null | head -1; }

kill_port() {
    local pids=$(lsof -ti:$1 2>/dev/null || echo "")
    if [ -n "$pids" ]; then
        info "释放端口 $1..."
        echo "$pids" | xargs kill -9 2>/dev/null || true
        sleep 1
    fi
}

wait_health() {
    local retries=0
    while ! curl -s "http://localhost:$STANDALONE_PORT/health" > /dev/null 2>&1; do
        retries=$((retries + 1))
        if [ $retries -ge 60 ]; then
            error "服务启动超时，请检查日志: $STANDALONE_LOG_FILE"
            return 1
        fi
        sleep 1
    done
    return 0
}

# ============================================================
# 构建单二进制（前端 dist → backend/static → go build）
# ============================================================
build_frontend() {
    info "构建前端资源..."
    cd "$SCRIPT_DIR/$FRONTEND_DIR"

    if [ ! -d "node_modules" ]; then
        warning "node_modules 不存在，正在安装依赖..."
        npm install
        # 允许 esbuild 安装其二进制（npm allow-scripts 策略）
        npm approve-scripts esbuild 2>/dev/null || true
        npm rebuild esbuild 2>/dev/null || true
    fi

    npm run build
    success "前端构建完成: $FRONTEND_DIR/dist"
    cd "$SCRIPT_DIR"
}

build_binary() {
    build_frontend

    info "拷贝前端产物到 backend/static 并编译 $STANDALONE_BIN..."
    rm -rf "$SCRIPT_DIR/$BACKEND_DIR/static"
    mkdir -p "$SCRIPT_DIR/$BACKEND_DIR/static"
    cp -R "$SCRIPT_DIR/$FRONTEND_DIR/dist/." "$SCRIPT_DIR/$BACKEND_DIR/static/"

    cd "$SCRIPT_DIR/$BACKEND_DIR"
    go build -trimpath -o "$SCRIPT_DIR/$STANDALONE_BIN" .
    cd "$SCRIPT_DIR"
    success "单二进制已生成: $SCRIPT_DIR/$STANDALONE_BIN"
}

# ============================================================
# 单二进制运行
# ============================================================
start_binary() {
    mkdir -p "$SCRIPT_DIR/logs"
    kill_port "$STANDALONE_PORT"

    info "启动 FlowStack (端口 $STANDALONE_PORT)..."
    PORT="$STANDALONE_PORT" GIN_MODE="${GIN_MODE:-release}" \
        nohup "$SCRIPT_DIR/$STANDALONE_BIN" >> "$STANDALONE_LOG_FILE" 2>&1 &
    echo $! > "$STANDALONE_PID_FILE"

    if wait_health; then
        success "FlowStack 已启动: http://localhost:$STANDALONE_PORT (PID: $(cat "$STANDALONE_PID_FILE"))"
    else
        tail -20 "$STANDALONE_LOG_FILE"
        return 1
    fi
}

stop_all() {
    info "正在停止服务..."
    if [ -f "$STANDALONE_PID_FILE" ]; then
        local pid=$(cat "$STANDALONE_PID_FILE" 2>/dev/null || echo "")
        if [ -n "$pid" ] && kill -0 "$pid" 2>/dev/null; then
            kill "$pid" 2>/dev/null || true
        fi
        rm -f "$STANDALONE_PID_FILE"
    fi
    if [ -f "$BACKEND_DEV_PID_FILE" ]; then
        local pid=$(cat "$BACKEND_DEV_PID_FILE" 2>/dev/null || echo "")
        if [ -n "$pid" ] && kill -0 "$pid" 2>/dev/null; then
            kill "$pid" 2>/dev/null || true
        fi
        rm -f "$BACKEND_DEV_PID_FILE"
    fi
    kill_port "$STANDALONE_PORT"
    kill_port "$FRONTEND_DEV_PORT"
    success "服务已停止"
}

show_status() {
    info "服务状态:"
    if [ -n "$(check_port $STANDALONE_PORT)" ]; then
        success "FlowStack: 运行中 (http://localhost:$STANDALONE_PORT)"
    else
        warning "FlowStack: 未运行"
    fi
    if [ -n "$(check_port $FRONTEND_DEV_PORT)" ]; then
        success "Vite dev: 运行中 (http://localhost:$FRONTEND_DEV_PORT)"
    fi
    [ -x "$SCRIPT_DIR/$STANDALONE_BIN" ] && success "二进制: $SCRIPT_DIR/$STANDALONE_BIN"
}

# ============================================================
# 开发模式：gin(9527) + vite(5173 代理 /api)
# ============================================================
dev_mode() {
    info "开发模式: 后端 gin ($STANDALONE_PORT) + 前端 Vite ($FRONTEND_DEV_PORT)"

    kill_port "$STANDALONE_PORT"
    mkdir -p "$SCRIPT_DIR/logs"
    cd "$SCRIPT_DIR/$BACKEND_DIR"
    PORT="$STANDALONE_PORT" GIN_MODE=debug go run . >> "$SCRIPT_DIR/logs/backend-dev.log" 2>&1 &
    echo $! > "$BACKEND_DEV_PID_FILE"
    cd "$SCRIPT_DIR"

    if ! wait_health; then
        error "后端启动失败，查看 logs/backend-dev.log"
        return 1
    fi
    success "后端已启动: http://localhost:$STANDALONE_PORT"

    cd "$SCRIPT_DIR/$FRONTEND_DIR"
    [ ! -d "node_modules" ] && { npm install; npm approve-scripts esbuild 2>/dev/null || true; npm rebuild esbuild 2>/dev/null || true; }
    info "启动 Vite（Ctrl+C 退出，退出后自动停止后端）..."
    trap 'kill $(cat "$BACKEND_DEV_PID_FILE" 2>/dev/null) 2>/dev/null; rm -f "$BACKEND_DEV_PID_FILE"; exit 0' INT TERM EXIT
    npm run dev
}

# ============================================================
# 命令入口
# ============================================================
show_help() {
    echo "$PROJECT_NAME 发布系统启动脚本"
    echo ""
    echo "用法: ./run.sh [命令]"
    echo ""
    echo "命令:"
    echo "  start     构建并启动单二进制服务（默认，含前端资源）"
    echo "  stop      停止所有服务"
    echo "  restart   重启服务"
    echo "  build     仅构建单二进制 $STANDALONE_BIN"
    echo "  dev       开发模式：gin + Vite 热更新"
    echo "  backend   仅启动后端 API（开发用）"
    echo "  status    查看服务状态"
    echo "  help      显示帮助"
    echo ""
    echo "环境变量:"
    echo "  PORT      服务端口（默认 9527）"
    echo ""
    echo "示例:"
    echo "  ./run.sh            # 一键启动，访问 http://localhost:9527"
    echo "  PORT=9000 ./run.sh  # 指定端口"
    echo "  ./run.sh dev        # 前后端热更新开发"
}

main() {
    local command=${1:-start}

    # 依赖检查
    if [[ "$command" =~ ^(start|build|dev|backend)$ ]]; then
        command -v go &> /dev/null || { error "Go 未安装"; exit 1; }
    fi
    if [[ "$command" =~ ^(start|build|dev)$ ]]; then
        command -v npm &> /dev/null || { error "npm 未安装，请先安装 Node.js"; exit 1; }
    fi

    case "$command" in
        start)
            info "========== $PROJECT_NAME =========="
            [ ! -x "$SCRIPT_DIR/$STANDALONE_BIN" ] && {
                warning "未找到 $STANDALONE_BIN，开始构建（首次约 1-3 分钟）..."
                build_binary
            }
            start_binary && {
                echo ""
                success "========== FlowStack 已启动 =========="
                info "访问地址:   http://localhost:$STANDALONE_PORT"
                info "健康检查:   http://localhost:$STANDALONE_PORT/health"
                info "停止服务:   ./run.sh stop"
                echo ""
            }
            ;;
        stop)
            stop_all
            ;;
        restart)
            stop_all
            sleep 1
            build_binary
            start_binary
            ;;
        build)
            build_binary
            ;;
        dev)
            dev_mode
            ;;
        backend)
            kill_port "$STANDALONE_PORT"
            mkdir -p "$SCRIPT_DIR/logs"
            cd "$SCRIPT_DIR/$BACKEND_DIR"
            PORT="$STANDALONE_PORT" GIN_MODE=debug go run . >> "$SCRIPT_DIR/logs/backend-dev.log" 2>&1 &
            echo $! > "$BACKEND_DEV_PID_FILE"
            cd "$SCRIPT_DIR"
            wait_health && success "后端 API: http://localhost:$STANDALONE_PORT (日志: logs/backend-dev.log)"
            ;;
        status)
            show_status
            ;;
        help|--help|-h)
            show_help
            ;;
        *)
            error "未知命令: $command"
            show_help
            exit 1
            ;;
    esac
}

main "$@"