package callapiutils

import (
	"bytes"
	"encoding/json"
	"fmt"
	"io"
	"log"
	"net/http"
	"net/url"
	"strconv"
)

func AddQueryParamInt(u *url.URL, paramName string, paramValue int) {
	AddQueryParam(u, paramName, strconv.Itoa(paramValue))
}

func AddQueryParam(u *url.URL, paramName string, paramValue string) {
	q := u.Query()
	q.Set(paramName, paramValue)
	u.RawQuery = q.Encode()
}

func FetchAndParseResultFromPost[T any, J any](u *url.URL, queryArg *J, queryResult *T) error {
	payloadBuf := new(bytes.Buffer)
	json.NewEncoder(payloadBuf).Encode(queryArg)
	req, err := http.NewRequest("POST", u.String(), payloadBuf)
	if err != nil {
		return err
	}
	req.Header.Add("Content-Type", "application/json")
	req.Header.Add("Accept", "application/json")
	log.Printf("Calling POST %s", u.String())
	return parseApiQueryResult(u, req, queryResult)
}

func FetchAndParseResult[T any](u *url.URL, queryResult *T) error {
	req, err := http.NewRequest("GET", u.String(), nil)
	if err != nil {
		return err
	}
	req.Header.Add("Accept", "application/json")
	req.Header.Add("User-Agent", "bibliomane/0.1 (artlef@protonmail.com)")
	log.Printf("Calling GET %s", u.String())
	return parseApiQueryResult(u, req, queryResult)
}

func parseApiQueryResult[T any](u *url.URL, req *http.Request, queryResult *T) error {
	client := &http.Client{}
	resp, err := client.Do(req)
	if err != nil {
		return err
	}

	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		bodyError, err := io.ReadAll(resp.Body)
		if err != nil {
			return err
		}
		return fmt.Errorf("Call to %s returned code %d:\n%s", u.String(), resp.StatusCode, string(bodyError))
	}

	decoder := json.NewDecoder(resp.Body)
	err = decoder.Decode(queryResult)
	if err != nil {
		return err
	}

	return err
}

func ComputeUrl(baseUrl string, paths ...string) (*url.URL, error) {
	u, err := url.Parse(baseUrl)
	if err != nil {
		return nil, err
	}
	for _, p := range paths {
		u = u.JoinPath(p)
	}
	return u, nil
}