package eta_llm

import (
	"bufio"
	"bytes"
	"encoding/json"
	"errors"
	"eta/eta_api/models"
	"eta/eta_api/utils"
	"eta/eta_api/utils/llm"
	"eta/eta_api/utils/llm/eta_llm/eta_llm_http"
	"fmt"
	"io"
	"net/http"
	"strings"
	"sync"
)

var (
	dsOnce sync.Once

	etaLlmClient *ETALLMClient
)

const (
	KNOWLEDEG_CHAT_MODE            = "local_kb"
	DEFALUT_PROMPT_NAME            = "default"
	CONTENT_TYPE_JSON              = "application/json"
	KNOWLEDGE_BASE_CHAT_API        = "/chat/kb_chat"
	DOCUMENT_CHAT_API        = "/chat/file_chat"
	KNOWLEDGE_BASE_SEARCH_DOCS_API = "/knowledge_base/search_docs"
)

type ETALLMClient struct {
	*llm.LLMClient
	LlmModel string
}

type LLMConfig struct {
	LlmAddress string `json:"llm_server"`
	LlmModel   string `json:"llm_model"`
}

func GetInstance() llm.LLMService {
	dsOnce.Do(func() {
		confStr := models.BusinessConfMap[models.LLMInitConfig]
		if confStr == "" {
			utils.FileLog.Error("LLM配置为空")
			return
		}

		var config LLMConfig
		err := json.Unmarshal([]byte(confStr), &config)
		if err != nil {
			utils.FileLog.Error("LLM配置错误")
		}
		if etaLlmClient == nil {
			etaLlmClient = &ETALLMClient{
				LLMClient: llm.NewLLMClient(config.LlmAddress, 120),
				LlmModel:  config.LlmModel,
			}
		}
	})
	return etaLlmClient
}

func (ds *ETALLMClient) DocumentChat(query string, KnowledgeId string, history []string, stream bool) (llmRes *http.Response, err error) {
	ChatHistory := make([]eta_llm_http.HistoryContent, 0)
	for _, historyItemStr := range history {
		str := strings.Split(historyItemStr, "-")
		historyItem := eta_llm_http.HistoryContent{
			Role:    str[0],
			Content: str[1],
		}
		ChatHistory = append(ChatHistory, historyItem)
	}
	kbReq := eta_llm_http.DocumentChatRequest{
		Query:          query,
		KnowledgeId:    KnowledgeId,
		History:        ChatHistory,
		TopK:           3,
		ScoreThreshold: 0.5,
		Stream:         stream,
		ModelName:      ds.LlmModel,
		Temperature:    0.7,
		MaxTokens:      0,
		PromptName:     DEFALUT_PROMPT_NAME,
	}
	fmt.Printf("%v", kbReq.History)
	body, err := json.Marshal(kbReq)
	if err != nil {
		return
	}
	return ds.DoStreamPost(DOCUMENT_CHAT_API, body)
}
func (ds *ETALLMClient) KnowledgeBaseChat(query string, KnowledgeBaseName string, history []string) (llmRes *http.Response, err error) {
	ChatHistory := make([]eta_llm_http.HistoryContent, 0)
	for _, historyItemStr := range history {
		str := strings.Split(historyItemStr, "-")
		historyItem := eta_llm_http.HistoryContent{
			Role:    str[0],
			Content: str[1],
		}
		ChatHistory = append(ChatHistory, historyItem)
	}
	kbReq := eta_llm_http.KbChatRequest{
		Query:          query,
		Mode:           KNOWLEDEG_CHAT_MODE,
		KbName:         KnowledgeBaseName,
		History:        ChatHistory,
		TopK:           3,
		ScoreThreshold: 0.5,
		Stream:         true,
		Model:          ds.LlmModel,
		Temperature:    0.7,
		MaxTokens:      0,
		PromptName:     DEFALUT_PROMPT_NAME,
		ReturnDirect:   false,
	}
	fmt.Printf("%v", kbReq.History)
	body, err := json.Marshal(kbReq)
	if err != nil {
		return
	}
	return ds.DoStreamPost(KNOWLEDGE_BASE_CHAT_API, body)
}

func (ds *ETALLMClient) SearchKbDocs(query string, KnowledgeBaseName string) (content interface{}, err error) {
	kbReq := eta_llm_http.KbSearchDocsRequest{
		Query:             query,
		KnowledgeBaseName: KnowledgeBaseName,
		TopK:              10,
		ScoreThreshold:    0.5,
		Metadata:          struct{}{},
	}

	body, err := json.Marshal(kbReq)
	if err != nil {
		return
	}
	resp, err := ds.DoPost(KNOWLEDGE_BASE_SEARCH_DOCS_API, body)
	if !resp.Success {
		err = errors.New(resp.Msg)
		return
	}
	if resp.Data != nil {
		var kbSearchRes []eta_llm_http.SearchDocsResponse
		err = json.Unmarshal(resp.Data, &kbSearchRes)
		if err != nil {
			err = errors.New("搜索知识库失败")
			return
		}
		content = kbSearchRes
		return
	}
	err = errors.New("搜索知识库失败")
	return
}
func init() {
	err := llm.Register(llm.ETA_LLM_CLIENT, GetInstance())
	if err != nil {
		utils.FileLog.Error("注册eta_llm_server服务失败:", err)
	}
}

func (ds *ETALLMClient) DoPost(apiUrl string, body []byte) (baseResp eta_llm_http.BaseResponse, err error) {
	requestReader := bytes.NewReader(body)
	response, err := ds.HttpClient.Post(ds.BaseURL+apiUrl, CONTENT_TYPE_JSON, requestReader)
	if err != nil {
		return
	}
	return parseResponse(response)
}
func (ds *ETALLMClient) DoStreamPost(apiUrl string, body []byte) (baseResp *http.Response, err error) {
	requestReader := bytes.NewReader(body)
	return ds.HttpClient.Post(ds.BaseURL+apiUrl, CONTENT_TYPE_JSON, requestReader)
}
func parseResponse(response *http.Response) (baseResp eta_llm_http.BaseResponse, err error) {
	defer func() {
		_ = response.Body.Close()
	}()
	baseResp.Ret = response.StatusCode
	if response.StatusCode != http.StatusOK {
		baseResp.Msg = fmt.Sprintf("请求失败，状态码：%d, 状态信息：%s", response.StatusCode, http.StatusText(response.StatusCode))
		return
	}
	bodyBytes, err := io.ReadAll(response.Body)
	if err != nil {
		err = fmt.Errorf("读取响应体失败: %w", err)
		return
	}
	baseResp.Success = true
	baseResp.Data = bodyBytes
	return
}
func ParseStreamResponse(response *http.Response) (contentChan chan string, errChan chan error, closeChan chan struct{}) {
	contentChan = make(chan string, 10)
	errChan = make(chan error, 10)
	closeChan = make(chan struct{})
	go func() {
		defer close(contentChan)
		defer close(errChan)
		defer close(closeChan)
		scanner := bufio.NewScanner(response.Body)
		scanner.Split(bufio.ScanLines)
		for scanner.Scan() {
			line := scanner.Text()
			if line == "" {
				continue
			}
			// 忽略 "ping" 行
			if strings.HasPrefix(line, ": ping") {
				continue
			}
			// 去除 "data: " 前缀
			if strings.HasPrefix(line, "data: ") {
				line = strings.TrimPrefix(line, "data: ")
			}
			var chunk eta_llm_http.ChunkResponse
			if err := json.Unmarshal([]byte(line), &chunk); err != nil {
				fmt.Println("解析错误的line:" + line)
				errChan <- fmt.Errorf("解析 JSON 块失败: %w", err)
				return
			}
			// 处理每个 chunk
			if chunk.Choices != nil && len(chunk.Choices) > 0 {
				for _, choice := range chunk.Choices {
					if choice.Delta.Content != "" {
						contentChan <- choice.Delta.Content
					}
				}
			}
		}
		if err := scanner.Err(); err != nil {
			errChan <- fmt.Errorf("读取响应体失败: %w", err)
			return
		}
	}()
	return
}