//
//  Copyright 2026 The InfiniFlow Authors. All Rights Reserved.
//
//  Licensed under the Apache License, Version 2.0 (the "License");
//  you may not use this file except in compliance with the License.
//  You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
//  Unless required by applicable law or agreed to in writing, software
//  distributed under the License is distributed on an "AS IS" BASIS,
//  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
//  See the License for the specific language governing permissions and
//  limitations under the License.
//

package models

import (
	"bufio"
	"bytes"
	"context"
	"encoding/json"
	"fmt"
	"io"
	"mime/multipart"
	"net/http"
	"os"
	"path/filepath"
	"strings"
)

// RAGconModel implements ModelDriver for RAGcon (https://connect.ragcon.com),
// a LiteLLM-proxy gateway exposing OpenAI-compatible endpoints for chat,
// embedding, rerank, ASR and TTS. Model names are user-supplied (no fixed
// catalog), matching the Ollama/Xinference-style providers.
type RAGconModel struct {
	baseModel BaseModel
}

// NewRAGconModel creates a new RAGcon model instance.
func NewRAGconModel(baseURL map[string]string, urlSuffix URLSuffix) *RAGconModel {
	return &RAGconModel{
		baseModel: BaseModel{
			BaseURL:    baseURL,
			URLSuffix:  urlSuffix,
			httpClient: NewDriverHTTPClient(),
		},
	}
}

func (r *RAGconModel) NewInstance(baseURL map[string]string) ModelDriver {
	return NewRAGconModel(baseURL, r.baseModel.URLSuffix)
}

func (r *RAGconModel) Name() string {
	return "ragcon"
}

func (r *RAGconModel) chatURL(apiConfig *APIConfig) (string, error) {
	baseURL, err := r.baseModel.GetBaseURL(apiConfig)
	if err != nil {
		return "", err
	}
	baseURL = strings.TrimSuffix(baseURL, "/")
	return fmt.Sprintf("%s/%s", baseURL, r.baseModel.URLSuffix.Chat), nil
}

func ragconChatMessages(messages []Message) []map[string]interface{} {
	apiMessages := make([]map[string]interface{}, len(messages))
	for i, msg := range messages {
		apiMsg := map[string]interface{}{
			"role":    msg.Role,
			"content": msg.Content,
		}
		if msg.ToolCallID != "" {
			apiMsg["tool_call_id"] = msg.ToolCallID
		}
		if len(msg.ToolCalls) > 0 {
			apiMsg["tool_calls"] = msg.ToolCalls
		}
		apiMessages[i] = apiMsg
	}
	return apiMessages
}

func ragconChatPayload(modelName string, messages []Message, stream bool, chatModelConfig *ChatConfig) map[string]interface{} {
	reqBody := map[string]interface{}{
		"model":    modelName,
		"messages": ragconChatMessages(messages),
		"stream":   stream,
	}
	if stream {
		reqBody["stream_options"] = map[string]interface{}{"include_usage": true}
	}

	if chatModelConfig != nil {
		if chatModelConfig.MaxTokens != nil {
			reqBody["max_tokens"] = *chatModelConfig.MaxTokens
		}
		if chatModelConfig.Temperature != nil {
			reqBody["temperature"] = *chatModelConfig.Temperature
		}
		if chatModelConfig.TopP != nil {
			reqBody["top_p"] = *chatModelConfig.TopP
		}
		if chatModelConfig.Stop != nil {
			reqBody["stop"] = *chatModelConfig.Stop
		}
		if chatModelConfig.Tools != nil {
			reqBody["tools"] = chatModelConfig.Tools
			tc := "auto"
			if chatModelConfig.ToolChoice != nil {
				tc = *chatModelConfig.ToolChoice
			}
			reqBody["tool_choice"] = tc
		}
	}

	// Qwen3 family: disable thinking by default (mirrors the same policy
	// applied by the other OpenAI-compatible Go drivers).
	if strings.Contains(strings.ToLower(modelName), "qwen3") && (chatModelConfig == nil || chatModelConfig.Thinking == nil) {
		reqBody["enable_thinking"] = false
	}

	return reqBody
}

func (r *RAGconModel) ChatWithMessages(modelName string, messages []Message, apiConfig *APIConfig, chatModelConfig *ChatConfig) (*ChatResponse, error) {
	if err := r.baseModel.APIConfigCheck(apiConfig); err != nil {
		return nil, err
	}
	if strings.TrimSpace(modelName) == "" {
		return nil, fmt.Errorf("model name is required")
	}
	if len(messages) == 0 {
		return nil, fmt.Errorf("messages is empty")
	}

	url, err := r.chatURL(apiConfig)
	if err != nil {
		return nil, err
	}

	jsonData, err := json.Marshal(ragconChatPayload(modelName, messages, false, chatModelConfig))
	if err != nil {
		return nil, fmt.Errorf("failed to marshal request: %w", err)
	}

	ctx, cancel := context.WithTimeout(context.Background(), nonStreamCallTimeout)
	defer cancel()

	req, err := http.NewRequestWithContext(ctx, http.MethodPost, url, bytes.NewBuffer(jsonData))
	if err != nil {
		return nil, fmt.Errorf("failed to create request: %w", err)
	}
	req.Header.Set("Content-Type", "application/json")
	req.Header.Set("Authorization", fmt.Sprintf("Bearer %s", *apiConfig.ApiKey))

	resp, err := r.baseModel.httpClient.Do(req)
	if err != nil {
		return nil, fmt.Errorf("failed to send request: %w", err)
	}
	defer resp.Body.Close()

	body, err := io.ReadAll(resp.Body)
	if err != nil {
		return nil, fmt.Errorf("failed to read response: %w", err)
	}
	if resp.StatusCode != http.StatusOK {
		return nil, fmt.Errorf("RAGcon API request failed with status %d: %s", resp.StatusCode, string(body))
	}

	var result map[string]interface{}
	if err = json.Unmarshal(body, &result); err != nil {
		return nil, fmt.Errorf("failed to parse response: %w", err)
	}

	choices, ok := result["choices"].([]interface{})
	if !ok || len(choices) == 0 {
		return nil, fmt.Errorf("no choices in response")
	}
	firstChoice, ok := choices[0].(map[string]interface{})
	if !ok {
		return nil, fmt.Errorf("invalid choice format")
	}
	messageMap, ok := firstChoice["message"].(map[string]interface{})
	if !ok {
		return nil, fmt.Errorf("invalid message format")
	}

	var content string
	if c, ok := messageMap["content"].(string); ok {
		content = c
	}

	var reasonContent string
	if rc, ok := messageMap["reasoning_content"].(string); ok {
		reasonContent = rc
	} else if rc, ok := messageMap["reasoning"].(string); ok {
		reasonContent = rc
	}

	var toolCalls []map[string]interface{}
	if tcs, ok := messageMap["tool_calls"].([]interface{}); ok {
		for _, tc := range tcs {
			if tcMap, ok := tc.(map[string]interface{}); ok {
				toolCalls = append(toolCalls, tcMap)
			}
		}
	}

	chatResponse := &ChatResponse{
		Answer:        &content,
		ReasonContent: &reasonContent,
		ToolCalls:     toolCalls,
	}
	if pt, ct, tt := extractUsageFromMap(result); tt > 0 {
		chatResponse.Usage = &ChatUsage{PromptTokens: pt, CompletionTokens: ct, TotalTokens: tt}
	}

	return chatResponse, nil
}

func (r *RAGconModel) ChatStreamlyWithSender(modelName string, messages []Message, apiConfig *APIConfig, chatModelConfig *ChatConfig, sender func(*string, *string) error) error {
	if err := r.baseModel.APIConfigCheck(apiConfig); err != nil {
		return err
	}
	if sender == nil {
		return fmt.Errorf("sender is required")
	}
	if strings.TrimSpace(modelName) == "" {
		return fmt.Errorf("model name is required")
	}
	if len(messages) == 0 {
		return fmt.Errorf("messages is empty")
	}
	if chatModelConfig != nil && chatModelConfig.Stream != nil && !*chatModelConfig.Stream {
		return fmt.Errorf("stream must be true in ChatStreamlyWithSender")
	}

	url, err := r.chatURL(apiConfig)
	if err != nil {
		return err
	}

	jsonData, err := json.Marshal(ragconChatPayload(modelName, messages, true, chatModelConfig))
	if err != nil {
		return fmt.Errorf("failed to marshal request: %w", err)
	}

	req, err := http.NewRequestWithContext(context.Background(), http.MethodPost, url, bytes.NewBuffer(jsonData))
	if err != nil {
		return fmt.Errorf("failed to create request: %w", err)
	}
	req.Header.Set("Content-Type", "application/json")
	req.Header.Set("Authorization", fmt.Sprintf("Bearer %s", *apiConfig.ApiKey))

	resp, err := r.baseModel.httpClient.Do(req)
	if err != nil {
		return fmt.Errorf("failed to send request: %w", err)
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		body, _ := io.ReadAll(resp.Body)
		return fmt.Errorf("RAGcon API request failed with status %d: %s", resp.StatusCode, string(body))
	}

	sawTerminal := false
	accumulatedToolCalls := make(map[int]map[string]interface{})
	var streamUsage *ChatUsage

	scanner := bufio.NewScanner(resp.Body)
	scanner.Buffer(make([]byte, 64*1024), 1024*1024)
	for scanner.Scan() {
		line := scanner.Text()
		if !strings.HasPrefix(line, "data:") {
			continue
		}
		data := strings.TrimSpace(line[5:])
		if data == "" {
			continue
		}
		if data == "[DONE]" {
			sawTerminal = true
			break
		}

		var event map[string]interface{}
		if err = json.Unmarshal([]byte(data), &event); err != nil {
			continue
		}

		if pt, ct, tt := extractUsageFromMap(event); tt > 0 {
			streamUsage = &ChatUsage{PromptTokens: pt, CompletionTokens: ct, TotalTokens: tt}
		}

		choices, ok := event["choices"].([]interface{})
		if !ok || len(choices) == 0 {
			continue
		}
		firstChoice, ok := choices[0].(map[string]interface{})
		if !ok {
			continue
		}
		delta, ok := firstChoice["delta"].(map[string]interface{})
		if !ok {
			continue
		}

		if tcs, ok := delta["tool_calls"].([]interface{}); ok {
			for _, tc := range tcs {
				tcMap, ok := tc.(map[string]interface{})
				if !ok {
					continue
				}
				idxF, ok := tcMap["index"].(float64)
				if !ok {
					continue
				}
				idx := int(idxF)
				if existing, hasExisting := accumulatedToolCalls[idx]; hasExisting {
					if fn, ok := tcMap["function"].(map[string]interface{}); ok {
						if args, ok := fn["arguments"].(string); ok {
							if ef, ok := existing["function"].(map[string]interface{}); ok {
								if ea, ok := ef["arguments"].(string); ok {
									ef["arguments"] = ea + args
								} else {
									ef["arguments"] = args
								}
							}
						}
					}
				} else {
					accumulatedToolCalls[idx] = cloneMap(tcMap)
				}
			}
			continue
		}

		if reasoningContent, ok := delta["reasoning_content"].(string); ok && reasoningContent != "" {
			if err := sender(nil, &reasoningContent); err != nil {
				return err
			}
		}
		if content, ok := delta["content"].(string); ok && content != "" {
			if err := sender(&content, nil); err != nil {
				return err
			}
		}
		if finishReason, ok := firstChoice["finish_reason"].(string); ok && finishReason != "" {
			sawTerminal = true
		}
	}
	if err := scanner.Err(); err != nil {
		return fmt.Errorf("failed to scan response body: %w", err)
	}
	if !sawTerminal {
		return fmt.Errorf("ragcon: stream ended before [DONE] or finish_reason")
	}

	if len(accumulatedToolCalls) > 0 && chatModelConfig != nil {
		tcs := make([]map[string]interface{}, 0, len(accumulatedToolCalls))
		for _, tc := range accumulatedToolCalls {
			tcs = append(tcs, tc)
		}
		chatModelConfig.ToolCallsResult = &tcs
	}
	if streamUsage != nil && chatModelConfig != nil {
		chatModelConfig.UsageResult = streamUsage
	}

	endOfStream := "[DONE]"
	return sender(&endOfStream, nil)
}

type ragconEmbeddingResponse struct {
	Data []struct {
		Embedding []float64 `json:"embedding"`
		Index     int       `json:"index"`
	} `json:"data"`
}

func (r *RAGconModel) Embed(modelName *string, texts []string, apiConfig *APIConfig, embeddingConfig *EmbeddingConfig) ([]EmbeddingData, error) {
	if err := r.baseModel.APIConfigCheck(apiConfig); err != nil {
		return nil, err
	}
	if modelName == nil || strings.TrimSpace(*modelName) == "" {
		return nil, fmt.Errorf("model name is required")
	}
	if len(texts) == 0 {
		return []EmbeddingData{}, nil
	}

	baseURL, err := r.baseModel.GetBaseURL(apiConfig)
	if err != nil {
		return nil, err
	}
	baseURL = strings.TrimSuffix(baseURL, "/")
	url := fmt.Sprintf("%s/%s", baseURL, r.baseModel.URLSuffix.Embedding)

	reqBody := map[string]interface{}{
		"model": *modelName,
		"input": texts,
	}
	if embeddingConfig != nil && embeddingConfig.Dimension > 0 {
		reqBody["dimensions"] = embeddingConfig.Dimension
	}

	jsonData, err := json.Marshal(reqBody)
	if err != nil {
		return nil, fmt.Errorf("failed to marshal request: %w", err)
	}

	ctx, cancel := context.WithTimeout(context.Background(), nonStreamCallTimeout)
	defer cancel()

	req, err := http.NewRequestWithContext(ctx, http.MethodPost, url, bytes.NewBuffer(jsonData))
	if err != nil {
		return nil, fmt.Errorf("failed to create request: %w", err)
	}
	req.Header.Set("Content-Type", "application/json")
	req.Header.Set("Authorization", fmt.Sprintf("Bearer %s", *apiConfig.ApiKey))

	resp, err := r.baseModel.httpClient.Do(req)
	if err != nil {
		return nil, fmt.Errorf("failed to send request: %w", err)
	}
	defer resp.Body.Close()

	body, err := io.ReadAll(resp.Body)
	if err != nil {
		return nil, fmt.Errorf("failed to read response: %w", err)
	}
	if resp.StatusCode != http.StatusOK {
		return nil, fmt.Errorf("RAGcon embeddings API error: %s, body: %s", resp.Status, string(body))
	}

	var parsed ragconEmbeddingResponse
	if err = json.Unmarshal(body, &parsed); err != nil {
		return nil, fmt.Errorf("failed to parse response: %w", err)
	}

	embeddings := make([]EmbeddingData, 0, len(parsed.Data))
	for _, d := range parsed.Data {
		embeddings = append(embeddings, EmbeddingData{Embedding: d.Embedding, Index: d.Index})
	}
	return embeddings, nil
}

// Rerank POSTs to RAGcon's /rerank endpoint (LiteLLM proxy passthrough).
func (r *RAGconModel) Rerank(modelName *string, query string, documents []string, apiConfig *APIConfig, rerankConfig *RerankConfig) (*RerankResponse, error) {
	if err := r.baseModel.APIConfigCheck(apiConfig); err != nil {
		return nil, err
	}
	if modelName == nil || strings.TrimSpace(*modelName) == "" {
		return nil, fmt.Errorf("model name is required")
	}
	if len(documents) == 0 {
		return &RerankResponse{}, nil
	}

	baseURL, err := r.baseModel.GetBaseURL(apiConfig)
	if err != nil {
		return nil, err
	}
	baseURL = strings.TrimSuffix(baseURL, "/")
	url := fmt.Sprintf("%s/%s", baseURL, r.baseModel.URLSuffix.Rerank)

	topN := len(documents)
	if rerankConfig != nil && rerankConfig.TopN != 0 {
		topN = rerankConfig.TopN
	}

	reqBody := map[string]interface{}{
		"model":     *modelName,
		"query":     query,
		"documents": documents,
		"top_n":     topN,
	}

	jsonData, err := json.Marshal(reqBody)
	if err != nil {
		return nil, fmt.Errorf("failed to marshal request: %w", err)
	}

	ctx, cancel := context.WithTimeout(context.Background(), nonStreamCallTimeout)
	defer cancel()

	req, err := http.NewRequestWithContext(ctx, http.MethodPost, url, bytes.NewBuffer(jsonData))
	if err != nil {
		return nil, fmt.Errorf("failed to create request: %w", err)
	}
	req.Header.Set("Content-Type", "application/json")
	req.Header.Set("Authorization", fmt.Sprintf("Bearer %s", *apiConfig.ApiKey))

	resp, err := r.baseModel.httpClient.Do(req)
	if err != nil {
		return nil, fmt.Errorf("failed to send request: %w", err)
	}
	defer resp.Body.Close()

	body, err := io.ReadAll(resp.Body)
	if err != nil {
		return nil, fmt.Errorf("failed to read response: %w", err)
	}
	if resp.StatusCode != http.StatusOK {
		return nil, fmt.Errorf("RAGcon rerank API error: status %d, body: %s", resp.StatusCode, string(body))
	}

	var rerankResp struct {
		Results []struct {
			Index          int     `json:"index"`
			RelevanceScore float64 `json:"relevance_score"`
		} `json:"results"`
	}
	if err = json.Unmarshal(body, &rerankResp); err != nil {
		return nil, fmt.Errorf("failed to decode response: %w", err)
	}

	var rerankResponse RerankResponse
	for _, result := range rerankResp.Results {
		rerankResponse.Data = append(rerankResponse.Data, RerankResult{
			Index:          result.Index,
			RelevanceScore: result.RelevanceScore,
		})
	}
	return &rerankResponse, nil
}

// ListModels returns the model ids visible to the configured API key.
func (r *RAGconModel) ListModels(apiConfig *APIConfig) ([]ListModelResponse, error) {
	if err := r.baseModel.APIConfigCheck(apiConfig); err != nil {
		return nil, err
	}

	baseURL, err := r.baseModel.GetBaseURL(apiConfig)
	if err != nil {
		return nil, err
	}
	baseURL = strings.TrimSuffix(baseURL, "/")
	url := fmt.Sprintf("%s/%s", baseURL, r.baseModel.URLSuffix.Models)

	ctx, cancel := context.WithTimeout(context.Background(), nonStreamCallTimeout)
	defer cancel()

	req, err := http.NewRequestWithContext(ctx, http.MethodGet, url, nil)
	if err != nil {
		return nil, fmt.Errorf("failed to create request: %w", err)
	}
	req.Header.Set("Content-Type", "application/json")
	req.Header.Set("Authorization", fmt.Sprintf("Bearer %s", *apiConfig.ApiKey))

	resp, err := r.baseModel.httpClient.Do(req)
	if err != nil {
		return nil, fmt.Errorf("failed to send request: %w", err)
	}
	defer resp.Body.Close()

	body, err := io.ReadAll(resp.Body)
	if err != nil {
		return nil, fmt.Errorf("failed to read response: %w", err)
	}
	if resp.StatusCode != http.StatusOK {
		return nil, fmt.Errorf("API request failed with status %d: %s", resp.StatusCode, string(body))
	}

	var modelList ModelList
	if err = json.Unmarshal(body, &modelList); err != nil {
		return nil, fmt.Errorf("failed to parse response: %w", err)
	}

	return ParseListModel(modelList), nil
}

func (r *RAGconModel) CheckConnection(apiConfig *APIConfig) error {
	_, err := r.ListModels(apiConfig)
	return err
}

// Balance is not exposed by RAGcon's LiteLLM proxy.
func (r *RAGconModel) Balance(apiConfig *APIConfig) (map[string]interface{}, error) {
	return nil, fmt.Errorf("%s, no such method", r.Name())
}

func (r *RAGconModel) newASRRequest(ctx context.Context, modelName *string, file *string, apiConfig *APIConfig, asrConfig *ASRConfig, stream bool) (*http.Request, string, error) {
	if err := r.baseModel.APIConfigCheck(apiConfig); err != nil {
		return nil, "", err
	}
	if modelName == nil || strings.TrimSpace(*modelName) == "" {
		return nil, "", fmt.Errorf("model name is required")
	}
	if file == nil || *file == "" {
		return nil, "", fmt.Errorf("file is missing")
	}

	baseURL, err := r.baseModel.GetBaseURL(apiConfig)
	if err != nil {
		return nil, "", err
	}
	baseURL = strings.TrimSuffix(baseURL, "/")
	url := fmt.Sprintf("%s/%s", baseURL, strings.TrimPrefix(r.baseModel.URLSuffix.ASR, "/"))

	var body bytes.Buffer
	writer := multipart.NewWriter(&body)

	// codeql[go/path-injection] False positive: *file is the audio file path the caller passes in to upload. The caller (an operator-supplied pipeline) explicitly chose this path, and the OS access check enforces permissions anyway.
	audioFile, err := os.Open(*file)
	if err != nil {
		return nil, "", fmt.Errorf("failed to open audio file: %w", err)
	}
	defer audioFile.Close()

	part, err := writer.CreateFormFile("file", filepath.Base(*file))
	if err != nil {
		return nil, "", fmt.Errorf("failed to create multipart file: %w", err)
	}
	if _, err = io.Copy(part, audioFile); err != nil {
		return nil, "", fmt.Errorf("failed to copy audio data: %w", err)
	}
	if err = writer.WriteField("model", *modelName); err != nil {
		return nil, "", fmt.Errorf("failed to write model field: %w", err)
	}

	responseFormat := ""
	if asrConfig != nil && asrConfig.Params != nil {
		if value, ok := asrConfig.Params["response_format"].(string); ok {
			responseFormat = value
		}
		for key, value := range asrConfig.Params {
			if stream && key == "stream" {
				continue
			}
			if err = writeOpenAIMultipartField(writer, key, value); err != nil {
				return nil, "", err
			}
		}
	}
	if stream {
		if err = writer.WriteField("stream", "true"); err != nil {
			return nil, "", fmt.Errorf("failed to write stream field: %w", err)
		}
	}

	if err = writer.Close(); err != nil {
		return nil, "", fmt.Errorf("failed to close multipart writer: %w", err)
	}

	req, err := http.NewRequestWithContext(ctx, http.MethodPost, url, &body)
	if err != nil {
		return nil, "", fmt.Errorf("failed to create request: %w", err)
	}
	req.Header.Set("Authorization", fmt.Sprintf("Bearer %s", *apiConfig.ApiKey))
	req.Header.Set("Content-Type", writer.FormDataContentType())
	return req, responseFormat, nil
}

func (r *RAGconModel) TranscribeAudio(modelName *string, file *string, apiConfig *APIConfig, asrConfig *ASRConfig) (*ASRResponse, error) {
	ctx, cancel := context.WithTimeout(context.Background(), nonStreamCallTimeout)
	defer cancel()

	req, responseFormat, err := r.newASRRequest(ctx, modelName, file, apiConfig, asrConfig, false)
	if err != nil {
		return nil, err
	}
	req.Header.Set("Accept", "application/json")

	resp, err := r.baseModel.httpClient.Do(req)
	if err != nil {
		return nil, fmt.Errorf("failed to send request: %w", err)
	}
	defer resp.Body.Close()

	respBody, err := io.ReadAll(resp.Body)
	if err != nil {
		return nil, fmt.Errorf("failed to read response body: %w", err)
	}
	if resp.StatusCode != http.StatusOK {
		return nil, fmt.Errorf("RAGcon ASR API error: %s, body: %s", resp.Status, string(respBody))
	}

	return decodeOpenAIASRResponse(respBody, responseFormat)
}

func (r *RAGconModel) TranscribeAudioWithSender(modelName *string, file *string, apiConfig *APIConfig, asrConfig *ASRConfig, sender func(*string, *string) error) error {
	if sender == nil {
		return fmt.Errorf("sender is required")
	}

	req, responseFormat, err := r.newASRRequest(context.Background(), modelName, file, apiConfig, asrConfig, true)
	if err != nil {
		return err
	}
	req.Header.Set("Accept", "text/event-stream")

	resp, err := r.baseModel.httpClient.Do(req)
	if err != nil {
		return fmt.Errorf("failed to send request: %w", err)
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		respBody, _ := io.ReadAll(resp.Body)
		return fmt.Errorf("RAGcon ASR stream API error: %s, body: %s", resp.Status, string(respBody))
	}

	if !strings.Contains(resp.Header.Get("Content-Type"), "text/event-stream") {
		respBody, err := io.ReadAll(resp.Body)
		if err != nil {
			return fmt.Errorf("failed to read response body: %w", err)
		}
		response, err := decodeOpenAIASRResponse(respBody, responseFormat)
		if err != nil {
			return err
		}
		if response != nil && response.Text != "" {
			if err = sender(&response.Text, nil); err != nil {
				return err
			}
		}
		done := "[DONE]"
		return sender(&done, nil)
	}

	sentDelta := false
	if _, err = ParseSSEStream[struct {
		Type  string `json:"type"`
		Delta string `json:"delta"`
		Text  string `json:"text"`
	}](resp.Body, func(event struct {
		Type  string `json:"type"`
		Delta string `json:"delta"`
		Text  string `json:"text"`
	}) error {
		switch {
		case event.Delta != "":
			if err = sender(&event.Delta, nil); err != nil {
				return err
			}
			sentDelta = true
		case event.Type == "transcript.text.segment" && event.Text != "":
			if err = sender(&event.Text, nil); err != nil {
				return err
			}
			sentDelta = true
		case event.Type == "transcript.text.done" && !sentDelta && event.Text != "":
			if err = sender(&event.Text, nil); err != nil {
				return err
			}
		}
		return nil
	}); err != nil {
		return fmt.Errorf("error reading RAGcon ASR stream: %w", err)
	}

	done := "[DONE]"
	return sender(&done, nil)
}

func (r *RAGconModel) newTTSRequest(ctx context.Context, modelName *string, audioContent *string, apiConfig *APIConfig, ttsConfig *TTSConfig, stream bool) (*http.Request, string, error) {
	if err := r.baseModel.APIConfigCheck(apiConfig); err != nil {
		return nil, "", err
	}
	if modelName == nil || strings.TrimSpace(*modelName) == "" {
		return nil, "", fmt.Errorf("model name is required")
	}
	if audioContent == nil || *audioContent == "" {
		return nil, "", fmt.Errorf("audio content is empty")
	}

	baseURL, err := r.baseModel.GetBaseURL(apiConfig)
	if err != nil {
		return nil, "", err
	}
	baseURL = strings.TrimSuffix(baseURL, "/")
	url := fmt.Sprintf("%s/%s", baseURL, strings.TrimPrefix(r.baseModel.URLSuffix.TTS, "/"))

	reqBody := map[string]interface{}{
		"model": *modelName,
		"input": *audioContent,
	}
	if ttsConfig != nil && ttsConfig.Params != nil {
		for key, value := range ttsConfig.Params {
			reqBody[key] = value
		}
	}
	if ttsConfig != nil && ttsConfig.Format != "" {
		reqBody["response_format"] = ttsConfig.Format
	}
	if stream {
		if _, ok := reqBody["stream_format"]; !ok {
			reqBody["stream_format"] = "audio"
		}
	}

	voice, ok := reqBody["voice"]
	if !ok || voice == nil {
		return nil, "", fmt.Errorf("voice is required")
	}
	voiceString, ok := voice.(string)
	if !ok || strings.TrimSpace(voiceString) == "" {
		return nil, "", fmt.Errorf("voice is required")
	}

	streamFormat, _ := reqBody["stream_format"].(string)

	jsonData, err := json.Marshal(reqBody)
	if err != nil {
		return nil, "", fmt.Errorf("failed to marshal request: %w", err)
	}

	req, err := http.NewRequestWithContext(ctx, http.MethodPost, url, bytes.NewBuffer(jsonData))
	if err != nil {
		return nil, "", fmt.Errorf("failed to create request: %w", err)
	}
	req.Header.Set("Content-Type", "application/json")
	req.Header.Set("Authorization", fmt.Sprintf("Bearer %s", *apiConfig.ApiKey))
	return req, streamFormat, nil
}

func (r *RAGconModel) AudioSpeech(modelName *string, audioContent *string, apiConfig *APIConfig, ttsConfig *TTSConfig) (*TTSResponse, error) {
	ctx, cancel := context.WithTimeout(context.Background(), nonStreamCallTimeout)
	defer cancel()

	req, _, err := r.newTTSRequest(ctx, modelName, audioContent, apiConfig, ttsConfig, false)
	if err != nil {
		return nil, err
	}

	resp, err := r.baseModel.httpClient.Do(req)
	if err != nil {
		return nil, fmt.Errorf("failed to send request: %w", err)
	}
	defer resp.Body.Close()

	body, err := io.ReadAll(resp.Body)
	if err != nil {
		return nil, fmt.Errorf("failed to read response body: %w", err)
	}
	if resp.StatusCode != http.StatusOK {
		return nil, fmt.Errorf("RAGcon TTS API error: %s, body: %s", resp.Status, string(body))
	}

	return &TTSResponse{Audio: body}, nil
}

func (r *RAGconModel) AudioSpeechWithSender(modelName *string, audioContent *string, apiConfig *APIConfig, ttsConfig *TTSConfig, sender func(*string, *string) error) error {
	if sender == nil {
		return fmt.Errorf("sender is required")
	}

	req, streamFormat, err := r.newTTSRequest(context.Background(), modelName, audioContent, apiConfig, ttsConfig, true)
	if err != nil {
		return err
	}
	if streamFormat == "sse" {
		req.Header.Set("Accept", "text/event-stream")
	}

	resp, err := r.baseModel.httpClient.Do(req)
	if err != nil {
		return fmt.Errorf("failed to send request: %w", err)
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		body, _ := io.ReadAll(resp.Body)
		return fmt.Errorf("RAGcon TTS stream API error: %s, body: %s", resp.Status, string(body))
	}

	if streamFormat == "sse" || strings.Contains(resp.Header.Get("Content-Type"), "text/event-stream") {
		return readOpenAITTSSSEStream(resp.Body, sender)
	}
	return readOpenAITTSRawStream(resp.Body, sender)
}

// OCRFile is not offered by RAGcon.
func (r *RAGconModel) OCRFile(modelName *string, content []byte, url *string, apiConfig *APIConfig, ocrConfig *OCRConfig) (*OCRFileResponse, error) {
	return nil, fmt.Errorf("%s, no such method", r.Name())
}

// ParseFile is not offered by RAGcon.
func (r *RAGconModel) ParseFile(modelName *string, content []byte, url *string, apiConfig *APIConfig, parseFileConfig *ParseFileConfig) (*ParseFileResponse, error) {
	return nil, fmt.Errorf("%s, no such method", r.Name())
}

func (r *RAGconModel) ListTasks(apiConfig *APIConfig) ([]ListTaskStatus, error) {
	return nil, fmt.Errorf("%s, no such method", r.Name())
}

func (r *RAGconModel) ShowTask(taskID string, apiConfig *APIConfig) (*TaskResponse, error) {
	return nil, fmt.Errorf("%s, no such method", r.Name())
}