package gpt

import (
	"bytes"
	"encoding/json"
	"fmt"
	"io/ioutil"
	"net/http"

	"github.com/eryajf/chatgpt-dingtalk/config"
	"github.com/eryajf/chatgpt-dingtalk/public/logger"
)

const BASEURL = "https://api.openai.com/v1/"

// ChatGPTResponseBody 请求体
type ChatGPTResponseBody struct {
	ID      string                 `json:"id"`
	Object  string                 `json:"object"`
	Created int                    `json:"created"`
	Model   string                 `json:"model"`
	Choices []ChoiceItem           `json:"choices"`
	Usage   map[string]interface{} `json:"usage"`
}

type ChoiceItem struct {
	Text         string `json:"text"`
	Index        int    `json:"index"`
	Logprobs     int    `json:"logprobs"`
	FinishReason string `json:"finish_reason"`
}

// ChatGPTRequestBody 响应体
type ChatGPTRequestBody struct {
	Model       string  `json:"model"`
	Prompt      string  `json:"prompt"`
	MaxTokens   uint    `json:"max_tokens"`
	Temperature float64 `json:"temperature"`
}

// Completions gtp文本模型回复
//curl https://api.openai.com/v1/completions
//-H "Content-Type: application/json"
//-H "Authorization: Bearer your chatGPT key"
//-d '{"model": "text-davinci-003", "prompt": "give me good song", "temperature": 0, "max_tokens": 7}'
func Completions(msg string) (string, error) {
	cfg := config.LoadConfig()
	requestBody := ChatGPTRequestBody{
		Model:       cfg.Model,
		Prompt:      msg,
		MaxTokens:   cfg.MaxTokens,
		Temperature: cfg.Temperature,
	}
	requestData, err := json.Marshal(requestBody)
	if err != nil {
		return "", err
	}
	logger.Info(fmt.Sprintf("request gtp json string : %v", string(requestData)))
	req, err := http.NewRequest("POST", BASEURL+"completions", bytes.NewBuffer(requestData))
	if err != nil {
		return "", err
	}

	req.Header.Set("Content-Type", "application/json")
	req.Header.Set("Authorization", "Bearer "+cfg.ApiKey)
	client := &http.Client{Timeout: cfg.SessionTimeout}
	response, err := client.Do(req)
	if err != nil {
		return "", err
	}
	defer response.Body.Close()

	body, err := ioutil.ReadAll(response.Body)
	if err != nil {
		return "", err
	}

	if response.StatusCode != 200 {
		return "", fmt.Errorf("请求GTP出错了，gtp api status code not equals 200,code is %d ,details:  %v ", response.StatusCode, string(body))
	}
	logger.Info(fmt.Sprintf("response gtp json string : %v", string(body)))

	gptResponseBody := &ChatGPTResponseBody{}
	err = json.Unmarshal(body, gptResponseBody)
	if err != nil {
		return "", err
	}

	var reply string
	if len(gptResponseBody.Choices) > 0 {
		reply = gptResponseBody.Choices[0].Text
	}
	return reply, nil
}