//
//  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"
)

type OrcaRouterModel struct {
	baseModel BaseModel
}

func NewOrcaRouterModel(baseURL map[string]string, urlSuffix URLSuffix) *OrcaRouterModel {
	return &OrcaRouterModel{
		baseModel: BaseModel{
			BaseURL:    baseURL,
			URLSuffix:  urlSuffix,
			httpClient: NewDriverHTTPClient(false),
		},
	}
}

func (o *OrcaRouterModel) NewInstance(baseURL map[string]string) ModelDriver {
	return NewOrcaRouterModel(baseURL, o.baseModel.URLSuffix)
}

func (o *OrcaRouterModel) Name() string {
	return "orcarouter"
}

type OrcaRouterChatResponse struct {
	ID      string `json:"id"`
	Choices []struct {
		FinishReason string `json:"finish_reason"`
		Index        int    `json:"index"`
		Message      struct {
			Content   string           `json:"content"`
			Role      string           `json:"role"`
			ToolCalls []map[string]any `json:"tool_calls"`
		} `json:"message"`
		Logprobs interface{} `json:"logprobs"`
	} `json:"choices"`
	Created int    `json:"created"`
	Model   string `json:"model"`
	Object  string `json:"object"`
	Usage   struct {
		CompletionTokens int `json:"completion_tokens"`
		PromptTokens     int `json:"prompt_tokens"`
		TotalTokens      int `json:"total_tokens"`
	} `json:"usage"`
}

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

	resolvedBaseURL, err := o.baseModel.GetBaseURL(apiConfig)
	if err != nil {
		return nil, err
	}
	url := fmt.Sprintf("%s/%s", resolvedBaseURL, o.baseModel.URLSuffix.Chat)
	reqBody := buildRequestBody(chatModelConfig, modelName, messages, false)

	if chatModelConfig != nil {
		if chatModelConfig.Effort != nil {
			reqBody["reasoning_effort"] = *chatModelConfig.Effort
		}
	}

	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.Add("Content-Type", "application/json")
	req.Header.Add("Authorization", fmt.Sprintf("Bearer %s", *apiConfig.ApiKey))

	resp, err := o.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("failed to send request: %d %s", resp.StatusCode, string(body))
	}

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

		choice := &result.Choices[0]
		content := choice.Message.Content
		if content == "" && len(choice.Message.ToolCalls) == 0 {
			return chatResponseParts{}, fmt.Errorf("no message in response")
		}

		emptyReason := ""
		return chatResponseParts{
			RequestID:     result.ID,
			Content:       &content,
			ReasonContent: &emptyReason,
			ToolCalls:     choice.Message.ToolCalls,
			Usage: &TokenUsage{
				PromptTokens:     result.Usage.PromptTokens,
				CompletionTokens: result.Usage.CompletionTokens,
				TotalTokens:      result.Usage.TotalTokens,
			},
		}, nil
	})
}

func (o *OrcaRouterModel) ChatStreamlyWithSender(ctx context.Context, modelName string, messages []Message, apiConfig *APIConfig, modelConfig *ChatConfig, modelUsage *common.ModelUsage, sender func(*string, *string) error) error {
	if err := o.baseModel.APIConfigCheck(apiConfig); err != nil {
		return err
	}

	if len(messages) == 0 {
		return fmt.Errorf("messages is empty")
	}

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

	reqBody := buildRequestBody(modelConfig, modelName, messages, true)

	if modelConfig != nil {
		if modelConfig.Effort != nil {
			reqBody["reasoning_effort"] = *modelConfig.Effort
		}
	}

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

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

	req, err := http.NewRequestWithContext(ctx, "POST", 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 := o.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("invalid status code: %d, body: %s", resp.StatusCode, string(body))
	}

	// SSE parsing: read line by line
	sawTerminal := false
	accumulatedToolCalls := make(map[int]map[string]any)
	done, err := ParseSSEStream[map[string]interface{}](resp.Body, func(event map[string]interface{}) error {
		common.Info(fmt.Sprintf("%v", event))

		tokenUsage, found, usageErr := decodeOpenAICompatibleStreamUsage(event)
		if usageErr != nil {
			return usageErr
		}
		if found {
			applyStreamUsage(modelConfig, modelUsage, tokenUsage)
		}

		choices, ok := event["choices"].([]interface{})
		if !ok || len(choices) == 0 {
			return nil
		}

		firstChoice, ok := choices[0].(map[string]interface{})
		if !ok {
			return nil
		}

		delta, ok := firstChoice["delta"].(map[string]interface{})
		if !ok {
			return nil
		}

		accumulateToolCallDeltas(delta, accumulatedToolCalls)

		content, ok := delta["content"].(string)
		if ok && content != "" {
			if err := sender(&content, nil); err != nil {
				return err
			}
		}

		finishReason, ok := firstChoice["finish_reason"].(string)
		if ok && finishReason != "" {
			sawTerminal = true
		}
		return nil
	})
	if err != nil {
		return fmt.Errorf("failed to scan response body: %w", err)
	}
	setSortedToolCallsResult(modelConfig, accumulatedToolCalls)
	_ = done
	_ = sawTerminal

	// Send [DONE] marker for OpenAI compatibility
	endOfStream := "[DONE]"
	if err = sender(&endOfStream, nil); err != nil {
		return err
	}

	return nil
}

func (o *OrcaRouterModel) Embed(ctx context.Context, modelName *string, texts []string, apiConfig *APIConfig, embeddingConfig *EmbeddingConfig, modelUsage *common.ModelUsage) ([]EmbeddingData, error) {
	return nil, fmt.Errorf("%s no such method", o.Name())
}

func (o *OrcaRouterModel) Rerank(ctx context.Context, modelName *string, query string, documents []string, apiConfig *APIConfig, rerankConfig *RerankConfig, modelUsage *common.ModelUsage) (*RerankResponse, error) {
	return nil, fmt.Errorf("%s no such method", o.Name())
}

func (o *OrcaRouterModel) 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", o.Name())
}

func (o *OrcaRouterModel) 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", o.Name())
}

func (o *OrcaRouterModel) AudioSpeech(ctx context.Context, modelName *string, audioContent *string, apiConfig *APIConfig, ttsConfig *TTSConfig, modelUsage *common.ModelUsage) (*TTSResponse, error) {
	if err := o.baseModel.APIConfigCheck(apiConfig); err != nil {
		return nil, err
	}

	if audioContent == nil || *audioContent == "" {
		return nil, fmt.Errorf("audio content is empty")
	}

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

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

	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
	}

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

	ctx, cancel := context.WithTimeout(ctx, longOpCallTimeout)
	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 := o.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("%s - %s", resp.Status, string(body))
	}

	return &TTSResponse{Audio: body}, nil
}

func (o *OrcaRouterModel) 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", o.Name())
}

func (o *OrcaRouterModel) 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", o.Name())
}

func (o *OrcaRouterModel) 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", o.Name())
}

func (o *OrcaRouterModel) ListModels(ctx context.Context, apiConfig *APIConfig) ([]ListModelResponse, error) {
	if err := o.baseModel.APIConfigCheck(apiConfig); err != nil {
		return nil, err
	}

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

	reqBody := map[string]string{}

	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, "GET", 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 := o.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 modelList ModelList
	if err = json.Unmarshal(body, &modelList); err != nil {
		return nil, fmt.Errorf("failed to parse response: %w", err)
	}
	if modelList.Models == nil {
		return nil, fmt.Errorf("invalid models list format")
	}

	return ParseListModel(modelList), nil
}

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

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

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

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