package httpjson

import (
	"bytes"
	"encoding/json"
	"fmt"
	"io"
	"net/http"
	"sync"
	"time"
)

var (
	client *http.Client
	once   sync.Once // Consider allowing configuration parameters for the singleton
)

func getClient() *http.Client {
	once.Do(func() {
		client = &http.Client{
			Timeout: 10 * time.Second,
		}
	})
	return client
}

func Get[T any](url string) (*T, error) {
	client := getClient()
	resp, err := client.Get(url)
	if err != nil {
		return nil, err
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		return nil, fmt.Errorf("unexpected status code: %d", resp.StatusCode)
	}

	var result T
	body, err := io.ReadAll(resp.Body)
	if err != nil {
		return nil, err
	}

	if err := json.Unmarshal(body, &result); err != nil {
		return nil, err
	}

	return &result, nil
}

func Post[T any](url string, data T) (*http.Response, error) {
	client := getClient()
	body, err := json.Marshal(data)
	if err != nil {
		return nil, err
	}

	resp, err := client.Post(url, "application/json", bytes.NewBuffer(body))
	if err != nil {
		return nil, err
	}

	if resp.StatusCode != http.StatusCreated && resp.StatusCode != http.StatusOK {
		return resp, fmt.Errorf("unexpected status code: %d", resp.StatusCode)
	}

	return resp, nil
}

func Patch[T any](url string, data T) error {
	client := getClient()
	body, err := json.Marshal(data)
	if err != nil {
		return err
	}

	req, err := http.NewRequest(http.MethodPatch, url, bytes.NewBuffer(body))
	if err != nil {
		return err
	}
	req.Header.Set("Content-Type", "application/json")

	resp, err := client.Do(req)
	if err != nil {
		return err
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		return fmt.Errorf("unexpected status code: %d", resp.StatusCode)
	}

	return nil
}

func Delete(url string) error {
	client := getClient()
	req, err := http.NewRequest(http.MethodDelete, url, nil)
	if err != nil {
		return err
	}

	resp, err := client.Do(req)
	if err != nil {
		return err
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		return fmt.Errorf("unexpected status code: %d", resp.StatusCode)
	}

	return nil
}