package client

import (
	"bytes"
	"encoding/json"
	"errors"
	"io"
	"net/http"
	"os"
)

type EmbeddingsClient struct {
	url    string
	apiKey string

	Do func(req *http.Request) (*http.Response, error)
}

type EmbeddingsRequest struct {
	Model string `json:"model"`
	Input string `json:"input"`
}

type EmbeddingsData struct {
	Object     string    `json:"object"`
	Index      int       `json:"index"`
	Embeddings []float64 `json:"embedding"`
}

type EmbeddingsResponse struct {
	Object string           `json:"object"`
	Data   []EmbeddingsData `json:"data"`
}

func CreateEmbeddingsClient() EmbeddingsClient {
	apiKey := os.Getenv(OPENAI_API_KEY)

	if len(apiKey) == 0 {
		panic("No api key")
	}

	return EmbeddingsClient{
		apiKey: apiKey,
		url:    "https://api.openai.com/v1/embeddings",
		Do: func(req *http.Request) (*http.Response, error) {
			client := &http.Client{}
			return client.Do(req)
		},
	}
}

func (client EmbeddingsClient) getRequest(text string) (*http.Request, error) {
	embeddingsReq := EmbeddingsRequest{
		Model: "text-embedding-3-large",
		Input: text,
	}

	jsonEmbeddingsBody, err := json.Marshal(embeddingsReq)
	if err != nil {
		return nil, err
	}

	req, err := http.NewRequest("POST", client.url, bytes.NewBuffer(jsonEmbeddingsBody))
	if err != nil {
		return req, err
	}

	req.Header.Add("Authorization", "Bearer "+client.apiKey)
	req.Header.Add("Content-Type", "application/json")

	return req, nil
}

func (client EmbeddingsClient) Request(text string) (EmbeddingsData, error) {
	httpRequest, err := client.getRequest(text)
	if err != nil {
		return EmbeddingsData{}, err
	}

	resp, err := client.Do(httpRequest)
	if err != nil {
		return EmbeddingsData{}, err
	}

	response, err := io.ReadAll(resp.Body)
	if err != nil {
		return EmbeddingsData{}, err
	}

	embeddingsResponse := EmbeddingsResponse{}
	err = json.Unmarshal(response, &embeddingsResponse)

	if err != nil {
		return EmbeddingsData{}, err
	}

	if len(embeddingsResponse.Data) != 1 {
		return EmbeddingsData{}, errors.New("Unsupported. We currently only accept 1 choice from AI.")
	}

	return embeddingsResponse.Data[0], nil
}