package wechat

import (
	"context"
	"crypto/hmac"
	"crypto/md5"
	"crypto/sha256"
	"crypto/tls"
	"encoding/xml"
	"errors"
	"fmt"
	"hash"
	"strings"
	"sync"

	"github.com/go-pay/gopay"
	"github.com/go-pay/gopay/pkg/xhttp"
	"github.com/go-pay/xlog"
)

type Client struct {
	AppId       string
	MchId       string
	ApiKey      string
	BaseURL     string
	IsProd      bool
	DebugSwitch gopay.DebugSwitch
	logger      xlog.XLogger
	mu          sync.RWMutex
	sha256Hash  hash.Hash
	md5Hash     hash.Hash
	hc          *xhttp.Client
	tlsHc       *xhttp.Client
}

// 初始化微信客户端 V2
// appId：应用ID
// mchId：商户ID
// ApiKey：API秘钥值
// IsProd：是否是正式环境
func NewClient(appId, mchId, apiKey string, isProd bool) (client *Client) {
	logger := xlog.NewLogger()
	logger.SetLevel(xlog.DebugLevel)
	return &Client{
		AppId:       appId,
		MchId:       mchId,
		ApiKey:      apiKey,
		IsProd:      isProd,
		DebugSwitch: gopay.DebugOff,
		logger:      logger,
		sha256Hash:  hmac.New(sha256.New, []byte(apiKey)),
		md5Hash:     md5.New(),
		hc:          xhttp.NewClient(),
		tlsHc:       xhttp.NewClient(),
	}
}

// SetBodySize 设置http response body size(MB)
func (w *Client) SetBodySize(sizeMB int) {
	if sizeMB > 0 {
		w.hc.SetBodySize(sizeMB)
	}
}

// SetHttpClient 设置自定义的xhttp.Client
func (w *Client) SetHttpClient(client *xhttp.Client) {
	if client != nil {
		w.hc = client
	}
}

// SetTLSHttpClient 设置自定义的xhttp.Client
func (w *Client) SetTLSHttpClient(client *xhttp.Client) {
	if client != nil {
		w.tlsHc = client
	}
}

func (w *Client) SetLogger(logger xlog.XLogger) {
	if logger != nil {
		w.logger = logger
	}
}

// 向微信发送Post请求，对于本库未提供的微信API，可自行实现，通过此方法发送请求
// bm：请求参数的BodyMap
// path：接口地址去掉baseURL的path，例如：url为https://api.mch.weixin.qq.com/pay/micropay，只需传 pay/micropay
// tlsConfig：tls配置，如无需证书请求，传nil
func (w *Client) PostWeChatAPISelf(ctx context.Context, bm gopay.BodyMap, path string, tlsConfig *tls.Config) (bs []byte, err error) {
	return w.doProdPostSelf(ctx, bm, path, tlsConfig)
}

// 授权码查询openid（正式）
// 文档地址：https://pay.weixin.qq.com/wiki/doc/api/wxpay_v2/open/chapter4_8.shtml
func (w *Client) AuthCodeToOpenId(ctx context.Context, bm gopay.BodyMap) (wxRsp *AuthCodeToOpenIdResponse, err error) {
	err = bm.CheckEmptyError("nonce_str", "auth_code")
	if err != nil {
		return nil, err
	}

	bs, err := w.doProdPost(ctx, bm, authCodeToOpenid)
	if err != nil {
		return nil, err
	}
	wxRsp = new(AuthCodeToOpenIdResponse)
	if err = xml.Unmarshal(bs, wxRsp); err != nil {
		return nil, fmt.Errorf("[%w]: %v, bytes: %s", gopay.UnmarshalErr, err, string(bs))
	}
	return wxRsp, nil
}

// 下载对账单
// 文档地址：https://pay.weixin.qq.com/wiki/doc/api/wxpay_v2/open/chapter3_6.shtml
func (w *Client) DownloadBill(ctx context.Context, bm gopay.BodyMap) (wxRsp string, err error) {
	err = bm.CheckEmptyError("nonce_str", "bill_date", "bill_type")
	if err != nil {
		return gopay.NULL, err
	}
	billType := bm.GetString("bill_type")
	if billType != "ALL" && billType != "SUCCESS" && billType != "REFUND" && billType != "RECHARGE_REFUND" {
		return gopay.NULL, errors.New("bill_type error, please reference: https://pay.weixin.qq.com/wiki/doc/api/jsapi.php?chapter=9_6")
	}
	var bs []byte
	if w.IsProd {
		bs, err = w.doProdPost(ctx, bm, downloadBill)
	} else {
		bs, err = w.doSanBoxPost(ctx, bm, sandboxDownloadBill)
	}
	if err != nil {
		return gopay.NULL, err
	}
	return string(bs), nil
}

// 下载资金账单（正式）
// 注意：请在初始化client时，调用 client 添加证书的相关方法添加证书
// 不支持沙箱环境，因为沙箱环境默认需要用MD5签名，但是此接口仅支持HMAC-SHA256签名
// 文档地址：https://pay.weixin.qq.com/wiki/doc/api/wxpay_v2/open/chapter3_7.shtml
func (w *Client) DownloadFundFlow(ctx context.Context, bm gopay.BodyMap) (wxRsp string, err error) {
	err = bm.CheckEmptyError("nonce_str", "bill_date", "account_type")
	if err != nil {
		return gopay.NULL, err
	}
	accountType := bm.GetString("account_type")
	if accountType != "Basic" && accountType != "Operation" && accountType != "Fees" {
		return gopay.NULL, errors.New("account_type error, please reference: https://pay.weixin.qq.com/wiki/doc/api/jsapi.php?chapter=9_18&index=7")
	}
	bm.Set("sign_type", SignType_HMAC_SHA256)
	bs, err := w.doProdPostTLS(ctx, bm, downloadFundFlow)
	if err != nil {
		return gopay.NULL, err
	}
	wxRsp = string(bs)
	return
}

// 交易保障
// 文档地址：（JSAPI）https://pay.weixin.qq.com/wiki/doc/api/wxpay_v2/open/chapter3_9.shtml
// 文档地址：（付款码）https://pay.weixin.qq.com/wiki/doc/api/wxpay_v2/open/chapter4_9.shtml
// 文档地址：（Native）https://pay.weixin.qq.com/wiki/doc/api/wxpay_v2/open/chapter6_9.shtml
// 文档地址：（APP）https://pay.weixin.qq.com/wiki/doc/api/wxpay_v2/open/chapter7_9.shtml
// 文档地址：（H5）https://pay.weixin.qq.com/wiki/doc/api/wxpay_v2/open/chapter8_9.shtml
// 文档地址：（微信小程序）https://pay.weixin.qq.com/wiki/doc/api/wxpay_v2/open/chapter5_9.shtml
func (w *Client) Report(ctx context.Context, bm gopay.BodyMap) (wxRsp *ReportResponse, err error) {
	err = bm.CheckEmptyError("nonce_str", "interface_url", "execute_time", "return_code", "return_msg", "result_code", "user_ip")
	if err != nil {
		return nil, err
	}
	var bs []byte
	if w.IsProd {
		bs, err = w.doProdPost(ctx, bm, report)
	} else {
		bs, err = w.doSanBoxPost(ctx, bm, sandboxReport)
	}
	if err != nil {
		return nil, err
	}
	wxRsp = new(ReportResponse)
	if err = xml.Unmarshal(bs, wxRsp); err != nil {
		return nil, fmt.Errorf("[%w]: %v, bytes: %s", gopay.UnmarshalErr, err, string(bs))
	}
	return wxRsp, nil
}

// 拉取订单评价数据（正式）
// 注意：请在初始化client时，调用 client 添加证书的相关方法添加证书
// 不支持沙箱环境，因为沙箱环境默认需要用MD5签名，但是此接口仅支持HMAC-SHA256签名
// 文档地址：https://pay.weixin.qq.com/wiki/doc/api/wxpay_v2/open/chapter3_11.shtml
func (w *Client) BatchQueryComment(ctx context.Context, bm gopay.BodyMap) (wxRsp string, err error) {
	err = bm.CheckEmptyError("nonce_str", "begin_time", "end_time", "offset")
	if err != nil {
		return gopay.NULL, err
	}
	bm.Set("sign_type", SignType_HMAC_SHA256)
	bs, err := w.doProdPostTLS(ctx, bm, batchQueryComment)
	if err != nil {
		return gopay.NULL, err
	}
	return string(bs), nil
}

// doSanBoxPost sanbox环境post请求
func (w *Client) doSanBoxPost(ctx context.Context, bm gopay.BodyMap, path string) (bs []byte, err error) {
	var url = baseUrlCh + path
	bm.Set("appid", w.AppId)
	bm.Set("mch_id", w.MchId)

	if bm.GetString("sign") == gopay.NULL {
		bm.Set("sign_type", SignType_MD5)
		sign, err := w.getSandBoxSign(ctx, w.MchId, w.ApiKey, bm)
		if err != nil {
			return nil, err
		}
		bm.Set("sign", sign)
	}

	if w.BaseURL != gopay.NULL {
		url = w.BaseURL + path
	}
	req := GenerateXml(bm)
	if w.DebugSwitch == gopay.DebugOn {
		w.logger.Debugf("Wechat_Request: %s", req)
	}
	res, bs, err := w.hc.Req(xhttp.TypeXML).Post(url).SendString(req).EndBytes(ctx)
	if err != nil {
		return nil, err
	}
	if w.DebugSwitch == gopay.DebugOn {
		w.logger.Debugf("Wechat_Response: %d, %s", res.StatusCode, string(bs))
	}
	if res.StatusCode != 200 {
		return nil, fmt.Errorf("HTTP Request Error, StatusCode = %d", res.StatusCode)
	}
	if strings.Contains(string(bs), "HTML") || strings.Contains(string(bs), "html") {
		return nil, errors.New(string(bs))
	}
	return bs, nil
}

// Post请求、正式
func (w *Client) doProdPostSelf(ctx context.Context, bm gopay.BodyMap, path string, tlsConfig *tls.Config) (bs []byte, err error) {
	var url = baseUrlCh + path
	if bm.GetString("appid") == gopay.NULL {
		bm.Set("appid", w.AppId)
	}
	if bm.GetString("mch_id") == gopay.NULL {
		bm.Set("mch_id", w.MchId)
	}
	if bm.GetString("sign") == gopay.NULL {
		sign := w.getReleaseSign(w.ApiKey, bm.GetString("sign_type"), bm)
		bm.Set("sign", sign)
	}
	if w.BaseURL != gopay.NULL {
		url = w.BaseURL + path
	}
	req := GenerateXml(bm)
	if w.DebugSwitch == gopay.DebugOn {
		w.logger.Debugf("Wechat_Request: %s", req)
	}
	httpClient := xhttp.NewClient()
	if w.IsProd && tlsConfig != nil {
		httpClient.SetTLSConfig(tlsConfig)
	}
	res, bs, err := httpClient.Req(xhttp.TypeXML).Post(url).SendString(req).EndBytes(ctx)
	if err != nil {
		return nil, err
	}
	if w.DebugSwitch == gopay.DebugOn {
		w.logger.Debugf("Wechat_Response: %d, %s", res.StatusCode, string(bs))
	}
	if res.StatusCode != 200 {
		return nil, fmt.Errorf("HTTP Request Error, StatusCode = %d", res.StatusCode)
	}
	if strings.Contains(string(bs), "HTML") || strings.Contains(string(bs), "html") {
		return nil, errors.New(string(bs))
	}
	return bs, nil
}

// Post请求、正式
func (w *Client) doProdPost(ctx context.Context, bm gopay.BodyMap, path string) (bs []byte, err error) {
	var url = baseUrlCh + path
	if bm.GetString("appid") == gopay.NULL {
		bm.Set("appid", w.AppId)
	}
	if bm.GetString("mch_id") == gopay.NULL {
		bm.Set("mch_id", w.MchId)
	}
	if bm.GetString("sign") == gopay.NULL {
		sign := w.getReleaseSign(w.ApiKey, bm.GetString("sign_type"), bm)
		bm.Set("sign", sign)
	}
	if w.BaseURL != gopay.NULL {
		url = w.BaseURL + path
	}
	req := GenerateXml(bm)
	if w.DebugSwitch == gopay.DebugOn {
		w.logger.Debugf("Wechat_Request: %s", req)
	}
	res, bs, err := w.hc.Req(xhttp.TypeXML).Post(url).SendString(req).EndBytes(ctx)
	if err != nil {
		return nil, err
	}
	if w.DebugSwitch == gopay.DebugOn {
		w.logger.Debugf("Wechat_Response: %d, %s", res.StatusCode, string(bs))
	}
	if res.StatusCode != 200 {
		return nil, fmt.Errorf("HTTP Request Error, StatusCode = %d", res.StatusCode)
	}
	if strings.Contains(string(bs), "<HTML") || strings.Contains(string(bs), "<html") {
		return nil, errors.New(string(bs))
	}
	return bs, nil
}

func (w *Client) doProdPostTLS(ctx context.Context, bm gopay.BodyMap, path string) (bs []byte, err error) {
	var url = baseUrlCh + path
	if bm.GetString("appid") == gopay.NULL {
		bm.Set("appid", w.AppId)
	}
	if bm.GetString("mch_id") == gopay.NULL {
		bm.Set("mch_id", w.MchId)
	}
	if bm.GetString("sign") == gopay.NULL {
		sign := w.getReleaseSign(w.ApiKey, bm.GetString("sign_type"), bm)
		bm.Set("sign", sign)
	}
	if w.BaseURL != gopay.NULL {
		url = w.BaseURL + path
	}
	req := GenerateXml(bm)
	if w.DebugSwitch == gopay.DebugOn {
		w.logger.Debugf("Wechat_Request: %s", req)
	}
	res, bs, err := w.tlsHc.Req(xhttp.TypeXML).Post(url).SendString(req).EndBytes(ctx)
	if err != nil {
		return nil, err
	}
	if w.DebugSwitch == gopay.DebugOn {
		w.logger.Debugf("Wechat_Response: %d, %s", res.StatusCode, string(bs))
	}
	if res.StatusCode != 200 {
		return nil, fmt.Errorf("HTTP Request Error, StatusCode = %d", res.StatusCode)
	}
	if strings.Contains(string(bs), "<HTML") || strings.Contains(string(bs), "<html") {
		return nil, errors.New(string(bs))
	}
	return bs, nil
}

func (w *Client) doProdPostPure(ctx context.Context, bm gopay.BodyMap, path string) (bs []byte, err error) {
	var url = baseUrlCh + path
	if w.BaseURL != gopay.NULL {
		url = w.BaseURL + path
	}
	req := GenerateXml(bm)
	if w.DebugSwitch == gopay.DebugOn {
		w.logger.Debugf("Wechat_Request: %s", req)
	}
	res, bs, err := w.hc.Req(xhttp.TypeXML).Post(url).SendString(req).EndBytes(ctx)
	if err != nil {
		return nil, err
	}
	if w.DebugSwitch == gopay.DebugOn {
		w.logger.Debugf("Wechat_Response: %d, %s", res.StatusCode, string(bs))
	}
	if res.StatusCode != 200 {
		return nil, fmt.Errorf("HTTP Request Error, StatusCode = %d", res.StatusCode)
	}
	if strings.Contains(string(bs), "<HTML") || strings.Contains(string(bs), "<html") {
		return nil, errors.New(string(bs))
	}
	return bs, nil
}

func (w *Client) doProdPostPureTLS(ctx context.Context, bm gopay.BodyMap, path string) (bs []byte, err error) {
	var url = baseUrlCh + path
	if w.BaseURL != gopay.NULL {
		url = w.BaseURL + path
	}
	req := GenerateXml(bm)
	if w.DebugSwitch == gopay.DebugOn {
		w.logger.Debugf("Wechat_Request: %s", req)
	}
	res, bs, err := w.tlsHc.Req(xhttp.TypeXML).Post(url).SendString(req).EndBytes(ctx)
	if err != nil {
		return nil, err
	}
	if w.DebugSwitch == gopay.DebugOn {
		w.logger.Debugf("Wechat_Response: %d, %s", res.StatusCode, string(bs))
	}
	if res.StatusCode != 200 {
		return nil, fmt.Errorf("HTTP Request Error, StatusCode = %d", res.StatusCode)
	}
	if strings.Contains(string(bs), "<HTML") || strings.Contains(string(bs), "<html") {
		return nil, errors.New(string(bs))
	}
	return bs, nil
}

// Get请求、正式
func (w *Client) doProdGet(ctx context.Context, bm gopay.BodyMap, path, signType string) (bs []byte, err error) {
	var url = baseUrlCh + path
	if bm.GetString("appid") == gopay.NULL {
		bm.Set("appid", w.AppId)
	}
	if bm.GetString("mch_id") == gopay.NULL {
		bm.Set("mch_id", w.MchId)
	}
	bm.Remove("sign")
	sign := w.getReleaseSign(w.ApiKey, signType, bm)
	bm.Set("sign", sign)
	if w.BaseURL != gopay.NULL {
		url = w.BaseURL + path
	}
	if w.DebugSwitch == gopay.DebugOn {
		w.logger.Debugf("Wechat_Request: %s", bm.JsonBody())
	}
	param := bm.EncodeURLParams()
	uri := url + "?" + param
	res, bs, err := w.hc.Req(xhttp.TypeXML).Get(uri).EndBytes(ctx)
	if err != nil {
		return nil, err
	}
	if w.DebugSwitch == gopay.DebugOn {
		w.logger.Debugf("Wechat_Response: %d, %s", res.StatusCode, string(bs))
	}
	if res.StatusCode != 200 {
		return nil, fmt.Errorf("HTTP Request Error, StatusCode = %d", res.StatusCode)
	}
	if strings.Contains(string(bs), "<HTML") || strings.Contains(string(bs), "<html") {
		return nil, errors.New(string(bs))
	}
	return bs, nil
}