package pandoc

import (
	"bytes"
	"context"
	"encoding/json"
	"io"
	"net/http"
)

type Client struct {
	client  *http.Client
	address string
}

type PandocClient interface {
	ConvertLatexToHtml5(ctx context.Context, text string) (string, error)
}

func NewPandocClient(client *http.Client, address string) *Client {
	return &Client{
		client:  client,
		address: address,
	}
}

type convertRequest struct {
	Text string `json:"text"`
	From string `json:"from"`
	To   string `json:"to"`
}

func (client *Client) convert(ctx context.Context, text, from, to string) (string, error) {
	body, err := json.Marshal(convertRequest{
		Text: text,
		From: from,
		To:   to,
	})
	if err != nil {
		return "", err
	}

	buf := bytes.NewBuffer(body)

	req, err := http.NewRequestWithContext(ctx, http.MethodPost, client.address, buf)
	if err != nil {
		return "", err
	}
	req.Header.Set("Content-Type", "application/json")
	resp, err := client.client.Do(req)
	if err != nil {
		return "", err
	}

	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		return "", err
	}

	body, err = io.ReadAll(resp.Body)
	if err != nil {
		return "", err
	}

	return string(body), nil
}

func (client *Client) ConvertLatexToHtml5(ctx context.Context, text string) (string, error) {
	return client.convert(ctx, text, "latex", "html5")
}