package logic

import (
	"context"
	"errors"
	"log"
	"strconv"
	"time"

	"git.apinb.com/quant/coin/internal/impl"
	"git.apinb.com/quant/coin/internal/models"
	binance "github.com/adshao/go-binance/v2"
)

// OpenPosition 按交易对用配置的 OrderQtyUsdt 市价买入首笔；更新内存、写入数据库并 loadPortfolio 刷新持仓缓存。
// 若链上可用基础币名义已达「有仓」阈值则只同步数量与成本写库，不再重复下单。
func CreateNewSpotPosition(symbol string) error {
	ctx, cancel := context.WithTimeout(context.Background(), 45*time.Second)
	defer cancel()

	if err := RefreshAccount(); err != nil {
		return err
	} else {
		account := GetAccount("USDT")
		if account <= 10 {
			return errors.New("USDT 余额不足")
		}
	}

	qty, err := CalculateQty(symbol)
	if err != nil {
		return err
	}

	order, err := BinanceClient.NewCreateOrderService().
		Symbol(symbol).
		Side(binance.SideTypeBuy).
		Type(binance.OrderTypeMarket).
		Quantity(qty).
		NewOrderRespType(binance.NewOrderRespTypeRESULT).
		Do(ctx)
	if err != nil {
		return err
	}

	position := &models.SpotPosition{
		BaseAsset:   spotBaseFromSymbol(symbol),
		Symbol:      symbol,
		Quantity:    parseFloat(order.ExecutedQuantity),
		AvgCostUSDT: parseFloat(order.Price),
	}

	if err := impl.DBService.Create(position).Error; err != nil {
		return err
	}

	if err := loadPortfolio(); err != nil {
		log.Printf("logic: OpenPosition 刷新持仓缓存失败: %v", err)
	}

	return nil
}

func CalculateQty(symbol string) (string, error) {
	ctx, cancel := context.WithTimeout(context.Background(), 45*time.Second)
	defer cancel()
	prices, err := BinanceClient.NewListPricesService().Symbol(symbol).Do(ctx)
	if err != nil || len(prices) == 0 {
		return "", err
	}
	price, err := strconv.ParseFloat(prices[0].Price, 64)
	if err != nil || price <= 0 {
		return "", errors.New("现价无效")
	}
	cfg := getSymbolInfo(symbol)
	if cfg == nil {
		return "", errors.New("交易对不存在")
	}
	want := InvestUsdt[cfg.Symbol] / price
	step := cfg.LotSizeFilter().StepSize
	qtyStr, ok, err := formatQtyToLotStep(want, step)
	if err != nil {
		return "", err
	}
	if !ok {
		return "", errors.New("数量不足")
	}
	return qtyStr, nil
}