package jiyi

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

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

const defaultRequestTimeout = 4 * time.Second

// queryBillingAPIKeys 查询计费接口：未查得/空结果仍按成功返回空数据，由平台侧计费
var queryBillingAPIKeys = map[string]struct{}{
	"jy000008": {}, // 探针C
	"jy000017": {}, // 探针A
	"jy000019": {}, // 商业险有效性
	"jy000020": {}, // 交强险有效性
	"jy000022": {}, // 洞侦1.0
	"jy000028": {}, // 车VIN查车牌号
	"jy000042": {}, // 借贷意向验证3.0
	"jy000048": {}, // 申请借贷
	"jy000052": {}, // 无间司南-纯黑A版
}

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

// jiyiResponse 集奕通用响应
type jiyiResponse struct {
	Code  int         `json:"code"`
	Msg   string      `json:"msg"`
	Fee   string      `json:"fee"`
	SeqNo string      `json:"seqNo"`
	Data  interface{} `json:"data"`
}

// Response 对外暴露的响应别名，便于处理器取值
type Response = jiyiResponse

type serviceConfig struct {
	URL       string
	AppID     string
	AppSecret string
	Timeout   time.Duration
}

// JiyiService 集奕数据服务
type JiyiService struct {
	config serviceConfig
	logger *external_logger.ExternalServiceLogger
}

// NewJiyiService 创建集奕服务实例
func NewJiyiService(url, appID, appSecret string, timeout time.Duration, logger *external_logger.ExternalServiceLogger) *JiyiService {
	if timeout <= 0 {
		timeout = defaultRequestTimeout
	}
	return &JiyiService{
		config: serviceConfig{
			URL:       url,
			AppID:     appID,
			AppSecret: appSecret,
			Timeout:   timeout,
		},
		logger: logger,
	}
}

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

// CallAPI 调用集奕接口。opts 为空时按明文、不注入额外字段处理。
func (s *JiyiService) CallAPI(ctx context.Context, apiKey, apiPath string, body map[string]string, opts ...CallOptions) (*Response, 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
	}

	opt := DefaultCallOptions()
	if len(opts) > 0 {
		opt = opts[0]
	}

	requestBody := cloneBody(body)
	switch opt.Mode {
	case CallModeBodyEncrypt:
		encType := opt.EncryptValue
		if _, ok := requestBody["timestamp"]; !ok || strings.TrimSpace(requestBody["timestamp"]) == "" {
			requestBody["timestamp"] = strconv.FormatInt(time.Now().UnixMilli(), 10)
		}
		requestBody["encryptType"] = strconv.Itoa(encType)
		if encType == 1 {
			requestBody = encryptBodyMD5(requestBody)
		}
	case CallModeTopEncrypt:
		if opt.EncryptValue == 2 {
			requestBody = encryptBodyMD5(requestBody)
		}
	}

	sign := Sign(requestBody, s.config.AppSecret)

	requestPayload := map[string]interface{}{
		"appId":  s.config.AppID,
		"sign":   sign,
		"apiKey": apiKey,
		"body":   requestBody,
	}
	if opt.Mode == CallModeTopEncrypt {
		encVal := opt.EncryptValue
		if encVal <= 0 {
			encVal = 1
		}
		// 顶层 encryptionType：部分接口要求 JSON number，统一传整型
		requestPayload["encryptionType"] = encVal
	}

	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 jiyiResp jiyiResponse
	if err := json.Unmarshal(respBody, &jiyiResp); 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 jiyiResp.Code != CodeSuccess {
		jiyiErr := NewJiyiError(jiyiResp.Code, jiyiResp.Msg)
		err = errors.Join(GetErrByPlatformCode(jiyiResp.Code), jiyiErr)
		s.logError(transactionID, apiKey, jiyiResp.SeqNo, jiyiErr, requestPayload)
		return nil, err
	}

	if jiyiResp.Data == nil {
		// 部分接口查空时 data 可能为 null
		if isQueryBillingAPIKey(apiKey) {
			jiyiResp.Data = map[string]interface{}{}
			s.logResponse(transactionID, apiKey, resp.StatusCode, duration, jiyiResp.SeqNo)
			return &jiyiResp, nil
		}
		err = errors.Join(ErrNotFound, errors.New("响应 data 为空"))
		s.logError(transactionID, apiKey, jiyiResp.SeqNo, err, requestPayload)
		return nil, err
	}

	busiCode, busiMsg, ok := parseDataBusiInfo(jiyiResp.Data)
	if !ok || (busiCode == 0 && strings.TrimSpace(busiMsg) == "") {
		err = errors.Join(ErrSystem, errors.New("响应 data 无法解析 busiCode"))
		s.logError(transactionID, apiKey, jiyiResp.SeqNo, err, requestPayload)
		return nil, err
	}

	if busiCode != BusiCodeSuccess {
		// 查询计费产品：未查得仍返回空数据，由平台计费
		if busiCode == BusiCodeNotFound && isQueryBillingAPIKey(apiKey) {
			jiyiResp.Data = map[string]interface{}{}
			s.logResponse(transactionID, apiKey, resp.StatusCode, duration, jiyiResp.SeqNo)
			return &jiyiResp, nil
		}
		busiErr := NewJiyiBusiError(busiCode, busiMsg)
		err = errors.Join(GetErrByBusiCode(busiCode), busiErr)
		s.logError(transactionID, apiKey, jiyiResp.SeqNo, busiErr, requestPayload)
		return nil, err
	}

	cleanedData, err := stripBusiMetaFromData(jiyiResp.Data)
	if err != nil {
		err = errors.Join(ErrSystem, fmt.Errorf("响应 data 清理失败: %w", err))
		s.logError(transactionID, apiKey, jiyiResp.SeqNo, err, requestPayload)
		return nil, err
	}
	if isEmptyBusinessResult(cleanedData) {
		if isQueryBillingAPIKey(apiKey) {
			jiyiResp.Data = map[string]interface{}{}
			s.logResponse(transactionID, apiKey, resp.StatusCode, duration, jiyiResp.SeqNo)
			return &jiyiResp, nil
		}
		emptyErr := NewJiyiBusiError(BusiCodeNotFound, "未查得")
		err = errors.Join(ErrNotFound, emptyErr)
		s.logError(transactionID, apiKey, jiyiResp.SeqNo, err, requestPayload)
		return nil, err
	}
	jiyiResp.Data = cleanedData

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

	return &jiyiResp, nil
}

type jiyiDataBusiMeta struct {
	BusiCode int    `json:"busiCode"`
	BusiMsg  string `json:"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 jiyiDataBusiMeta
	if err := json.Unmarshal(raw, &meta); err != nil {
		return 0, "", false
	}
	return meta.BusiCode, meta.BusiMsg, true
}

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
}

// isEmptyBusinessResult 判断业务载荷是否为空（无 result，或 result 无有效内容）
func isEmptyBusinessResult(data interface{}) bool {
	payload, ok := data.(map[string]interface{})
	if !ok || len(payload) == 0 {
		return true
	}
	result, exists := payload["result"]
	if !exists || result == nil {
		return true
	}
	return isEmptyValue(result)
}

func isEmptyValue(v interface{}) bool {
	if v == nil {
		return true
	}
	switch x := v.(type) {
	case string:
		return strings.TrimSpace(x) == ""
	case map[string]interface{}:
		if len(x) == 0 {
			return true
		}
		for _, item := range x {
			if !isEmptyValue(item) {
				return false
			}
		}
		return true
	case []interface{}:
		return len(x) == 0
	default:
		return false
	}
}

func cloneBody(body map[string]string) map[string]string {
	if body == nil {
		return map[string]string{}
	}
	cloned := make(map[string]string, len(body)+2)
	for k, v := range body {
		cloned[k] = v
	}
	return cloned
}

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)
	}
}