#!/bin/bash
# 灰度回滚脚本：切回稳定版本流量
# 用法: ./scripts/rollback.sh [稳定版本号]

set -euo pipefail

STABLE_VERSION="${1:-current}"

echo "=========================================="
echo "  灰度回滚"
echo "  切回稳定版本: $STABLE_VERSION"
echo "=========================================="

# 1. 恢复Nginx全量到稳定版本
echo ""
echo ">>> 恢复Nginx全量流量到稳定版本..."

NGINX_CONF="${NGINX_CONF:-/etc/nginx/conf.d/saas-api.conf}"
if [[ -f "$NGINX_CONF" ]]; then
    # 找最近的备份
    LATEST_BAK=$(ls -t "${NGINX_CONF}".bak.* 2>/dev/null | head -1)
    if [[ -n "$LATEST_BAK" ]]; then
        cp "$LATEST_BAK" "$NGINX_CONF"
        echo "  从备份恢复: $LATEST_BAK"
    else
        echo "  未找到备份，请手动移除 canary upstream"
    fi
    
    nginx -t && nginx -s reload
    echo "  ✅ Nginx 已回滚"
fi

# 2. 停止灰度版本容器（保留30分钟以便排查）
echo ""
echo ">>> 灰度版本容器将在30分钟后停止（便于排查问题）"
echo "    立即停止请执行: docker stop saas-api-canary saas-worker-canary"

echo ""
echo "=========================================="
echo "  ✅ 回滚完成"
echo "  流量已全部切回稳定版本"
echo "=========================================="