package payment

import (
	"encoding/hex"
	"fmt"
	"net/url"
)

// CreatePaymentLink 创建支付链接
func (c *Client) CreatePaymentLink(req PaymentLinkRequest) (*PaymentLinkResponse, error) {
	payUrlTemplate := "%s&fromId=include_sb&tysdPayParams=%s&tysdShopid=%s&tysdEncryptKey=%s&returnUrl=%s&showTitleBar=%s"

	orderData := map[string]string{
		"merchantNo": c.cfg.MchtNo,
		"orderInfos": req.ProductName,
		"orderNo":    req.OrderNo,
		"amount":     req.Price,
		"successUrl": hex.EncodeToString([]byte(c.cfg.SuccessUrl + req.OrderNo)),
		"acctType":   "2",
		"notifyUrl":  hex.EncodeToString([]byte(c.cfg.SuccessUrl + req.OrderNo)),
	}

	signData := map[string]string{
		"merchantNo": c.cfg.MchtNo,
		"orderNo":    req.OrderNo,
		"amount":     req.Price,
	}

	sign, enKey, err := c.EncryptMobile(MapToString(orderData), MapToString(signData))
	if err != nil {
		return nil, fmt.Errorf("加密支付参数失败: %v", err)
	}

	payUrl := fmt.Sprintf(payUrlTemplate,
		req.BackUrl,
		sign,
		c.cfg.ShopId,
		enKey,
		url.QueryEscape(c.cfg.ReturnUrl),
		c.cfg.ShowTitleBar,
	)

	plainText := c.cfg.MchtNo + "|" + req.OrderNo + "|" + req.Price
	signature := HmacSha256To16(c.cfg.Sha, plainText)

	return &PaymentLinkResponse{
		OrderNo:   req.OrderNo,
		NotifyUrl: c.cfg.NotifyUrl,
		Sign:      signature,
		PlainText: plainText,
		PayUrl:    payUrl,
	}, nil
}

// CreatePaymentLinkWithBackUrl 创建支付链接（带 fromId 判断）
func (c *Client) CreatePaymentLinkWithBackUrl(req PaymentLinkRequest) (*PaymentLinkResponse, error) {
	var payUrlTemplate string
	if len(req.BackUrl) > 0 && (contains(req.BackUrl, "fromId")) {
		payUrlTemplate = "%s&tysdPayParams=%s&tysdShopid=%s&tysdEncryptKey=%s&returnUrl=%s&showTitleBar=%s"
	} else {
		payUrlTemplate = "%s&fromId=include_sb&tysdPayParams=%s&tysdShopid=%s&tysdEncryptKey=%s&returnUrl=%s&showTitleBar=%s"
	}

	orderData := map[string]string{
		"merchantNo": c.cfg.MchtNo,
		"orderInfos": req.ProductName,
		"orderNo":    req.OrderNo,
		"amount":     req.Price,
		"successUrl": hex.EncodeToString([]byte(c.cfg.SuccessUrl + req.OrderNo)),
		"acctType":   "2",
		"notifyUrl":  hex.EncodeToString([]byte(c.cfg.SuccessUrl + req.OrderNo)),
	}

	signData := map[string]string{
		"merchantNo": c.cfg.MchtNo,
		"orderNo":    req.OrderNo,
		"amount":     req.Price,
	}

	sign, enKey, err := c.EncryptMobile(MapToString(orderData), MapToString(signData))
	if err != nil {
		return nil, fmt.Errorf("加密支付参数失败: %v", err)
	}

	payUrl := fmt.Sprintf(payUrlTemplate,
		req.BackUrl,
		sign,
		c.cfg.ShopId,
		enKey,
		url.QueryEscape(c.cfg.ReturnUrl),
		c.cfg.ShowTitleBar,
	)

	plainText := c.cfg.MchtNo + "|" + req.OrderNo + "|" + req.Price
	signature := HmacSha256To16(c.cfg.Sha, plainText)

	return &PaymentLinkResponse{
		OrderNo:   req.OrderNo,
		NotifyUrl: c.cfg.NotifyUrl,
		Sign:      signature,
		PlainText: plainText,
		PayUrl:    payUrl,
	}, nil
}

func contains(s, substr string) bool {
	return len(s) > 0 && len(substr) > 0 && (s == substr || len(s) > len(substr) && s[:len(substr)] == substr)
}