package kingdee

import (
	"encoding/json"
	"errors"
	"strings"

	"kingdee-dbapi/config"
	"kingdee-dbapi/logger"
	"kingdee-dbapi/nsqclient"
)

// 通用sql查询接口

type SqlQueryMsg struct {
	Key     string // 请求
	Command string
	Success bool
	Message string
	Result  []byte
}

func SqlQueryHandle(msg []byte) error {
	var query SqlQueryMsg

	if err := json.Unmarshal(msg, &query); err != nil {
		logger.Warn("解析请求失败, err:%s, msg:%s", err.Error(), string(msg))
		return err
	}

	var sql = query.Command
	logger.Debug("接收到查询请求,%s", sql)

	if !sqlCheck(sql) {
		query.Message = "危险的sql语句, 拒绝执行"
		logger.Warn(query.Message)
	} else {
		result, err := execSqlCommand(sql)
		if err != nil {
			query.Message = err.Error()
			logger.Warn("sql执行失败:%s", query.Message)
		} else {
			query.Result = result
			query.Success = true
			logger.Warn("sql执行完成.")
		}
	}

	replyData, _ := json.Marshal(query)
	ok := nsqclient.Produce(config.Options.SqlReplyTopic, replyData)
	logger.Warn("应答查询请求结果:%t, key:%s", ok, query.Key)

	return nil
}

func execSqlCommand(sql string) ([]byte, error) {
	var result []interface{}

	if db == nil {
		return nil, errors.New("数据库未连接")
	}

	rows, err := db.Raw(sql).Rows()
	if err != nil {
		return nil, err
	}

	var cols []string
	for rows.Next() {
		//先获取所有的column
		if cols == nil {
			cols, _ = rows.Columns()
		}

		//建立俩个interface数组，columnPointers中存在columns的地址
		columns := make([]interface{}, len(cols))
		columnPointers := make([]interface{}, len(cols))
		for i := 0; i < len(columns); i++ {
			//赋值地址
			columnPointers[i] = &columns[i]
		}

		//扫描结果
		err = rows.Scan(columnPointers...)
		if err != nil {
			return nil, err
		}

		m := make(map[string]interface{})
		for i, colName := range cols {
			val := columnPointers[i].(*interface{})
			m[colName] = *val
		}

		result = append(result, m)
	}

	rb, _ := json.Marshal(result)

	return rb, nil
}

// 简单过滤下sql语句,拒绝增删改操作
func sqlCheck(sql string) bool {
	var dangerousWords = []string{"INSERT", "UPDATE", "DELETE", "ALTER", "DROP", "DECLARE", "EXECUTE", "EXEC", "INTO", "TRANCATE"}

	var upperStr = strings.ToUpper(sql)

	for _, word := range dangerousWords {
		if strings.Contains(upperStr, word) {
			return false
		}
	}

	return true
}