package nuoer

import (
	"bytes"
	"context"
	"encoding/json"
	"errors"
	"fmt"
	"io"
	"net/http"
	"strings"
	"time"

	"hyapi-server/internal/shared/external_logger"
)

const defaultRequestTimeout = 4 * time.Second

// queryBillingAPIKeys 查询计费接口：数据未查得(busiCode=1000)仍按成功计费，返回空数据
var queryBillingAPIKeys = map[string]struct{}{
	"idRiskTagV106":          {}, // 身份风险V106 idRiskTagV106
	"personalLawsuit_cv2":    {}, // 企业诉讼定制版 personallawsuit cv2
	"personalLawsuit_cv1":    {}, // 个人诉讼定制版personalLawsuit_cv1
	"loanRiskTagV11":         {}, // 借贷意向查询loanRiskTagV11
	"loanRiskTagV5":          {}, // 风险变量V5loanRiskTagV5
	"loanRiskTagV12":         {}, // 特殊名单 loanRiskTagV12
	"blackListV121_3_1":      {}, // 债务逾期黑名单V3_1 blackListV121 3 1
	"blackListV110":          {}, // 特殊名单V110  blackListV110
	"zhitong_ultra_v4_score": {}, // 智瞳分尊享版  zhitong ultra v4 score
	"zhixiangScore":          {}, // 智享分  zhixiangScore
	"loanRiskTagV8":          {}, // 风险变量V8  loanRiskTagV8
	"loanRiskTagV9":          {}, // 风险变量V9  loanRiskTagV9
	"loanRiskTagV10":         {}, // 风险变量V10  loanRiskTagV10
}

func isQueryBillingAPIKey(apiKey string) bool {
	_, ok := queryBillingAPIKeys[apiKey]
	return ok
}

// nuoerResponse 诺尔智汇通用响应
type nuoerResponse struct {
	Code  int         `json:"code"`
	Msg   string      `json:"msg"`
	SeqNo string      `json:"seqNo"`
	Data  interface{} `json:"data"`
}

// serviceConfig 诺尔智汇服务运行时配置
type serviceConfig struct {
	URL       string
	AppID     string
	AppSecret string
	Timeout   time.Duration
}

// NuoerService 诺尔智汇服务
type NuoerService struct {
	config serviceConfig
	logger *external_logger.ExternalServiceLogger
}

// NewNuoerService 创建诺尔智汇服务实例
func NewNuoerService(url, appID, appSecret string, timeout time.Duration, logger *external_logger.ExternalServiceLogger) *NuoerService {
	if timeout <= 0 {
		timeout = defaultRequestTimeout
	}
	return &NuoerService{
		config: serviceConfig{
			URL:       url,
			AppID:     appID,
			AppSecret: appSecret,
			Timeout:   timeout,
		},
		logger: logger,
	}
}

func (s *NuoerService) logResponse(transactionID, apiKey string, statusCode int, duration time.Duration, seqNo string) {
	if s.logger == nil {
		return
	}
	s.logger.LogResponse(seqNo, transactionID, apiKey, statusCode, duration)
}

func (s *NuoerService) logError(transactionID, apiKey, seqNo string, err error, payload interface{}) {
	if s.logger == nil {
		return
	}
	s.logger.LogError(seqNo, transactionID, apiKey, err, payload)
}

func (s *NuoerService) CallAPI(ctx context.Context, apiKey, apiPath string, body map[string]string, encryptionType ...int) (*nuoerResponse, error) {
	requestURL := strings.TrimSuffix(s.config.URL, "/")
	if apiPath != "" {
		if !strings.HasPrefix(apiPath, "/") {
			apiPath = "/" + apiPath
		}
		requestURL += apiPath
	}

	startTime := time.Now()

	var transactionID string
	if id, ok := ctx.Value("transaction_id").(string); ok {
		transactionID = id
	}

	var encType int
	if len(encryptionType) > 0 {
		encType = encryptionType[0]
	}

	requestBody := body
	if encType == 2 {
		requestBody = encryptBodyMD5(body)
	}

	// 对请求 body 全量参与加签（排除空值，按 key 升序，见 Sign）
	sign := Sign(requestBody, s.config.AppSecret)

	requestPayload := map[string]interface{}{
		"appId":  s.config.AppID,
		"sign":   sign,
		"apiKey": apiKey,
		"body":   requestBody,
	}
	if encType > 0 {
		requestPayload["encryptionType"] = encType
	}

	if s.logger != nil {
		s.logger.LogRequest("", transactionID, apiKey, requestURL)
	}

	bodyBytes, err := json.Marshal(requestPayload)
	if err != nil {
		err = errors.Join(ErrSystem, err)
		s.logError(transactionID, apiKey, "", err, requestPayload)
		return nil, err
	}

	req, err := http.NewRequestWithContext(ctx, http.MethodPost, requestURL, bytes.NewBuffer(bodyBytes))
	if err != nil {
		err = errors.Join(ErrSystem, err)
		s.logError(transactionID, apiKey, "", err, requestPayload)
		return nil, err
	}
	req.Header.Set("Content-Type", "application/json")

	client := &http.Client{Timeout: s.config.Timeout}
	resp, err := client.Do(req)
	if err != nil {
		err = wrapHTTPError(err)
		s.logError(transactionID, apiKey, "", err, requestPayload)
		return nil, err
	}
	defer resp.Body.Close()

	respBody, err := io.ReadAll(resp.Body)
	if err != nil {
		err = errors.Join(ErrSystem, err)
		s.logError(transactionID, apiKey, "", err, requestPayload)
		return nil, err
	}

	duration := time.Since(startTime)

	if resp.StatusCode != http.StatusOK {
		err = errors.Join(ErrDatasource, fmt.Errorf("HTTP状态码 %d", resp.StatusCode))
		s.logError(transactionID, apiKey, "", err, requestPayload)
		return nil, err
	}

	var nuoerResp nuoerResponse
	if err := json.Unmarshal(respBody, &nuoerResp); err != nil {
		err = errors.Join(ErrSystem, fmt.Errorf("响应解析失败: %w", err))
		s.logError(transactionID, apiKey, "", err, requestPayload)
		return nil, err
	}

	if nuoerResp.Code != CodeSuccess {
		if nuoerResp.Code == BusiCodeNotFound && isQueryBillingAPIKey(apiKey) {
			nuoerResp.Data = map[string]interface{}{}
			s.logResponse(transactionID, apiKey, resp.StatusCode, duration, nuoerResp.SeqNo)
			return &nuoerResp, nil
		}
		nuoerErr := NewNuoerError(nuoerResp.Code, nuoerResp.Msg)
		err = errors.Join(GetErrByPlatformCode(nuoerResp.Code), nuoerErr)
		s.logError(transactionID, apiKey, nuoerResp.SeqNo, nuoerErr, requestPayload)
		return nil, err
	}

	if nuoerResp.Data == nil {
		err = errors.Join(ErrSystem, errors.New("响应 data 为空"))
		s.logError(transactionID, apiKey, nuoerResp.SeqNo, err, requestPayload)
		return nil, err
	}

	busiCode, busiMsg, ok := parseDataBusiInfo(nuoerResp.Data)
	if !ok {
		err = errors.Join(ErrSystem, errors.New("响应 data 无法解析 busiCode"))
		s.logError(transactionID, apiKey, nuoerResp.SeqNo, err, requestPayload)
		return nil, err
	}

	if busiCode != BusiCodeSuccess {
		if busiCode == BusiCodeNotFound && isQueryBillingAPIKey(apiKey) {
			nuoerResp.Data = map[string]interface{}{}
			s.logResponse(transactionID, apiKey, resp.StatusCode, duration, nuoerResp.SeqNo)
			return &nuoerResp, nil
		}
		busiErr := NewNuoerBusiError(busiCode, busiMsg)
		err = errors.Join(GetErrByBusiCode(busiCode), busiErr)
		s.logError(transactionID, apiKey, nuoerResp.SeqNo, busiErr, requestPayload)
		return nil, err
	}

	cleanedData, err := stripBusiMetaFromData(nuoerResp.Data)
	if err != nil {
		err = errors.Join(ErrSystem, fmt.Errorf("响应 data 清理失败: %w", err))
		s.logError(transactionID, apiKey, nuoerResp.SeqNo, err, requestPayload)
		return nil, err
	}
	nuoerResp.Data = cleanedData

	s.logResponse(transactionID, apiKey, resp.StatusCode, duration, nuoerResp.SeqNo)

	return &nuoerResp, nil
}

// nuoerDataBusiMeta 业务层状态字段，仅用于解析校验，不对外返回
type nuoerDataBusiMeta struct {
	BusiCode int    `json:"busiCode"`
	BusiMsg  string `json:"busiMsg"`
}

// parseDataBusiInfo 从各接口不同的 data 结构中解析 busiCode、busiMsg
func parseDataBusiInfo(data interface{}) (busiCode int, busiMsg string, ok bool) {
	if data == nil {
		return 0, "", false
	}
	raw, err := json.Marshal(data)
	if err != nil {
		return 0, "", false
	}
	var meta nuoerDataBusiMeta
	if err := json.Unmarshal(raw, &meta); err != nil {
		return 0, "", false
	}
	return meta.BusiCode, meta.BusiMsg, true
}

// stripBusiMetaFromData 去掉 data 中的 busiCode、busiMsg，仅保留业务载荷
func stripBusiMetaFromData(data interface{}) (interface{}, error) {
	raw, err := json.Marshal(data)
	if err != nil {
		return nil, err
	}
	var payload map[string]interface{}
	if err := json.Unmarshal(raw, &payload); err != nil {
		return nil, err
	}
	delete(payload, "busiCode")
	delete(payload, "busiMsg")
	return payload, nil
}

func wrapHTTPError(err error) error {
	if err == context.DeadlineExceeded {
		return errors.Join(ErrDatasource, err)
	}
	if netErr, ok := err.(interface{ Timeout() bool }); ok && netErr.Timeout() {
		return errors.Join(ErrDatasource, err)
	}
	switch err.Error() {
	case "context deadline exceeded", "timeout", "Client.Timeout exceeded", "net/http: request canceled":
		return errors.Join(ErrDatasource, err)
	default:
		return errors.Join(ErrSystem, err)
	}
}