//
//  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 (
	"bytes"
	"context"
	"encoding/json"
	"fmt"
	"io"
	"net/http"
	"ragflow/internal/common"
	"strings"
	"time"
)

type JinaModel struct {
	baseModel BaseModel
}

func NewJinaModel(baseURL map[string]string, urlSuffix URLSuffix) *JinaModel {
	// Embed/Rerank/ListModels issue requests without a per-call context
	// deadline, so keep an explicit 90s client-level timeout to bound them.
	// Built on the shared transport via NewDriverHTTPClient.
	client := NewDriverHTTPClient()
	client.Timeout = 90 * time.Second
	return &JinaModel{
		baseModel: BaseModel{
			BaseURL:    baseURL,
			URLSuffix:  urlSuffix,
			httpClient: client,
		},
	}
}

func (j *JinaModel) NewInstance(baseURL map[string]string) ModelDriver {
	return NewJinaModel(baseURL, j.baseModel.URLSuffix)
}

func (j *JinaModel) Name() string {
	return "jina"
}

// JinaChatResponse mirrors Jina's OpenAI-compatible chat response.
type JinaChatResponse struct {
	ID      string `json:"id"`
	Object  string `json:"object"`
	Created int64  `json:"created"`
	Model   string `json:"model"`
	Choices []struct {
		FinishReason string `json:"finish_reason"`
		Index        int    `json:"index"`
		Logprobs     any    `json:"logprobs"`
		Message      struct {
			Content          string           `json:"content"`
			Reasoning        string           `json:"reasoning"`
			ReasoningContent string           `json:"reasoning_content"`
			Role             string           `json:"role"`
			ToolCalls        []map[string]any `json:"tool_calls"`
		} `json:"message"`
	} `json:"choices"`
	SystemFingerprint string `json:"system_fingerprint"`
	Usage             struct {
		CompletionTokens    int `json:"completion_tokens"`
		PromptTokens        int `json:"prompt_tokens"`
		TotalTokens         int `json:"total_tokens"`
		PromptTokensDetails struct {
			CachedTokens int `json:"cached_tokens"`
		} `json:"prompt_tokens_details"`
	} `json:"usage"`
}

// JinaEmbeddingResponse mirrors Jina's embeddings response. Embeddings is
// populated by multivector models such as jina-embeddings-v4.
type JinaEmbeddingResponse struct {
	ID     string `json:"id"`
	Object string `json:"object"`
	Model  string `json:"model"`
	Data   []struct {
		Object     string      `json:"object"`
		Embedding  []float64   `json:"embedding"`
		Embeddings [][]float64 `json:"embeddings"`
		Index      int         `json:"index"`
	} `json:"data"`
	Usage struct {
		PromptTokens int `json:"prompt_tokens"`
		TotalTokens  int `json:"total_tokens"`
	} `json:"usage"`
}

// JinaRerankResponse mirrors Jina's rerank response.
type JinaRerankResponse struct {
	ID      string `json:"id"`
	Model   string `json:"model"`
	Results []struct {
		Index    int `json:"index"`
		Document struct {
			Text string `json:"text"`
		} `json:"document"`
		RelevanceScore float64 `json:"relevance_score"`
	} `json:"results"`
	Usage struct {
		PromptTokens int `json:"prompt_tokens"`
		TotalTokens  int `json:"total_tokens"`
	} `json:"usage"`
}

func (j *JinaModel) ChatWithMessages(ctx context.Context, modelName string, messages []Message, apiConfig *APIConfig, chatModelConfig *ChatConfig, modelUsage *common.ModelUsage) (*ChatResponse, error) {
	if err := j.baseModel.APIConfigCheck(apiConfig); err != nil {
		return nil, err
	}
	if modelName == "" {
		return nil, fmt.Errorf("model name is required")
	}
	if len(messages) == 0 {
		return nil, fmt.Errorf("messages is empty")
	}

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

	reqBody := buildRequestBody(chatModelConfig, modelName, messages, false)

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

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

	req, err := http.NewRequestWithContext(ctx, "POST", 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 := j.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("Jina chat API error: status %d, body: %s", resp.StatusCode, string(body))
	}

	return parseChatCompletionResponse(body, chatModelConfig, modelUsage, func(body []byte, _ *ChatConfig) (chatResponseParts, error) {
		var result JinaChatResponse
		if err := json.Unmarshal(body, &result); err != nil {
			return chatResponseParts{}, fmt.Errorf("failed to parse response: %w", err)
		}
		if len(result.Choices) == 0 {
			return chatResponseParts{}, fmt.Errorf("no choices in response")
		}

		choice := result.Choices[0]
		if choice.Message.Content == "" && len(choice.Message.ToolCalls) == 0 {
			return chatResponseParts{}, fmt.Errorf("response contains neither content nor tool calls")
		}
		reasonContent := choice.Message.ReasoningContent
		if reasonContent == "" {
			reasonContent = choice.Message.Reasoning
		}
		reasonContent = strings.TrimPrefix(reasonContent, "\n")
		return chatResponseParts{
			RequestID:     result.ID,
			Content:       &choice.Message.Content,
			ReasonContent: &reasonContent,
			ToolCalls:     choice.Message.ToolCalls,
			Usage: &TokenUsage{
				PromptTokens:     result.Usage.PromptTokens,
				CompletionTokens: result.Usage.CompletionTokens,
				TotalTokens:      result.Usage.TotalTokens,
			},
		}, nil
	})
}

func (j *JinaModel) ChatStreamlyWithSender(ctx context.Context, modelName string, messages []Message, apiConfig *APIConfig, modelConfig *ChatConfig, modelUsage *common.ModelUsage, sender func(*string, *string) error) error {
	// Jina's public API does not expose a streaming chat-completions endpoint.
	return fmt.Errorf("jina does not implement ChatStreamlyWithSender(not available for now)")
}

func (j *JinaModel) Embed(ctx context.Context, modelName *string, texts []string, apiConfig *APIConfig, embeddingConfig *EmbeddingConfig, modelUsage *common.ModelUsage) ([]EmbeddingData, error) {
	if err := j.baseModel.APIConfigCheck(apiConfig); err != nil {
		return nil, err
	}

	if len(texts) == 0 {
		return []EmbeddingData{}, nil
	}
	if modelName == nil || strings.TrimSpace(*modelName) == "" {
		return nil, fmt.Errorf("model name is required")
	}

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

	reqBody := map[string]interface{}{
		"model": *modelName,
		"input": texts,
	}

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

	ctx, cancel := context.WithTimeout(ctx, 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 := j.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("Jina embedding API error: status %d, body: %s", resp.StatusCode, string(body))
	}

	var parsedResponse JinaEmbeddingResponse

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

	if len(parsedResponse.Data) == 0 {
		return nil, fmt.Errorf("Jina embedding response contains no data: %s", string(body))
	}
	recordResponseUsage(modelUsage, parsedResponse.ID, &TokenUsage{
		PromptTokens: parsedResponse.Usage.PromptTokens,
		TotalTokens:  parsedResponse.Usage.TotalTokens,
	}, "embedding")

	var embeddings []EmbeddingData
	for _, dataElem := range parsedResponse.Data {
		embedding := dataElem.Embedding
		if len(embedding) == 0 && len(dataElem.Embeddings) > 0 {
			dimensions := len(dataElem.Embeddings[0])
			if dimensions == 0 {
				return nil, fmt.Errorf("Jina embedding response contains an empty multivector at index %d", dataElem.Index)
			}
			embedding = make([]float64, dimensions)
			for _, vector := range dataElem.Embeddings {
				if len(vector) != dimensions {
					return nil, fmt.Errorf("Jina embedding response contains inconsistent multivector dimensions at index %d", dataElem.Index)
				}
				for i, value := range vector {
					embedding[i] += value
				}
			}
			for i := range embedding {
				embedding[i] /= float64(len(dataElem.Embeddings))
			}
		}
		if len(embedding) == 0 {
			return nil, fmt.Errorf("Jina embedding response contains an empty vector at index %d", dataElem.Index)
		}
		embeddings = append(embeddings, EmbeddingData{
			Embedding: embedding,
			Index:     dataElem.Index,
		})
	}

	return embeddings, nil
}

func (j *JinaModel) Rerank(ctx context.Context, modelName *string, query string, documents []string, apiConfig *APIConfig, rerankConfig *RerankConfig, modelUsage *common.ModelUsage) (*RerankResponse, error) {
	if err := j.baseModel.APIConfigCheck(apiConfig); err != nil {
		return nil, err
	}

	if len(documents) == 0 {
		return &RerankResponse{}, nil
	}
	if modelName == nil || strings.TrimSpace(*modelName) == "" {
		return nil, fmt.Errorf("model name is required")
	}

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

	topN := len(documents)
	if rerankConfig != nil && rerankConfig.TopN > 0 && rerankConfig.TopN < topN {
		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(ctx, 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 := j.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("Jina Rerank API error: status %d, body: %s", resp.StatusCode, string(body))
	}

	var rerankResp JinaRerankResponse

	if err = json.Unmarshal(body, &rerankResp); err != nil {
		return nil, fmt.Errorf("failed to decode response: %w", err)
	}
	recordResponseUsage(modelUsage, rerankResp.ID, &TokenUsage{
		PromptTokens: rerankResp.Usage.PromptTokens,
		TotalTokens:  rerankResp.Usage.TotalTokens,
	}, "rerank")

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

	return &rerankResponse, nil
}

func (j *JinaModel) ListModels(ctx context.Context, apiConfig *APIConfig) ([]ListModelResponse, error) {

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

	req, err := http.NewRequest("GET", url, nil)
	if err != nil {
		return nil, fmt.Errorf("failed to create request: %w", err)
	}

	req.Header.Set("Content-Type", "application/json")

	resp, err := j.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("API request failed with status %d: %s", resp.StatusCode, string(body))
	}

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

	// convert result["data"] to []map[string]interface{}
	models := make([]ModelListItem, 0, len(result["data"].([]interface{})))
	for _, model := range result["data"].([]interface{}) {
		modelName := model.(map[string]interface{})["name"].(string)
		models = append(models, ModelListItem{
			ID:      modelName,
			OwnedBy: "",
		})
	}
	// Jina list models: `Jina AI: Jina Embeddings v5 Text Nano`
	return ParseListModel(ModelList{Models: models}), nil
}

func (j *JinaModel) Balance(ctx context.Context, apiConfig *APIConfig) (map[string]interface{}, error) {
	return nil, fmt.Errorf("no such method")
}

func (j *JinaModel) CheckConnection(ctx context.Context, apiConfig *APIConfig) error {
	_, err := j.ListModels(ctx, apiConfig)
	return err
}

// TranscribeAudio transcribe audio
func (j *JinaModel) TranscribeAudio(ctx context.Context, modelName *string, file *string, apiConfig *APIConfig, asrConfig *ASRConfig, modelUsage *common.ModelUsage) (*ASRResponse, error) {
	return nil, fmt.Errorf("%s, no such method", j.Name())
}

func (j *JinaModel) TranscribeAudioWithSender(ctx context.Context, modelName *string, file *string, apiConfig *APIConfig, asrConfig *ASRConfig, modelUsage *common.ModelUsage, sender func(*string, *string) error) error {
	return fmt.Errorf("%s, no such method", j.Name())
}

// AudioSpeech convert text to audio
func (j *JinaModel) AudioSpeech(ctx context.Context, modelName *string, audioContent *string, apiConfig *APIConfig, ttsConfig *TTSConfig, modelUsage *common.ModelUsage) (*TTSResponse, error) {
	return nil, fmt.Errorf("%s, no such method", j.Name())
}

func (j *JinaModel) AudioSpeechWithSender(ctx context.Context, modelName *string, audioContent *string, apiConfig *APIConfig, ttsConfig *TTSConfig, modelUsage *common.ModelUsage, sender func(*string, *string) error) error {
	return fmt.Errorf("%s, no such method", j.Name())
}

// OCRFile OCR file
func (j *JinaModel) OCRFile(ctx context.Context, modelName *string, content []byte, url *string, apiConfig *APIConfig, ocrConfig *OCRConfig, modelUsage *common.ModelUsage) (*OCRFileResponse, error) {
	return nil, fmt.Errorf("%s, no such method", j.Name())
}

// ParseFile parse file
func (j *JinaModel) ParseFile(ctx context.Context, modelName *string, content []byte, url *string, apiConfig *APIConfig, parseFileConfig *ParseFileConfig, modelUsage *common.ModelUsage) (*ParseFileResponse, error) {
	return nil, fmt.Errorf("%s, no such method", j.Name())
}

func (j *JinaModel) ListTasks(ctx context.Context, apiConfig *APIConfig) ([]ListTaskStatus, error) {
	return nil, fmt.Errorf("%s, no such method", j.Name())
}

func (j *JinaModel) ShowTask(ctx context.Context, taskID string, apiConfig *APIConfig) (*TaskResponse, error) {
	return nil, fmt.Errorf("%s, no such method", j.Name())
}