package auth

import (
	"bytes"
	"encoding/json"
	"fmt"
	"log"
	"net/http"
	"path"
)

type ldapUser struct {
	User
	NumericId int    `json:"id"`
	Role      string `json:"role"`
	Gecos     string `json:"gecos"`
}

func (u ldapUser) AsUser() *User {
	return &User{
		Username: u.Username,
		Name:     u.Name,
		Surname:  u.Surname,
		Email:    u.Email,

		FullName: u.Gecos,
	}
}

type LDAPAuthService struct {
	Host string
}

func (a *LDAPAuthService) doGetRequest(url string, response interface{}) error {
	req, err := http.NewRequest(
		"GET", path.Join(a.Host, "ldap", url), bytes.NewBuffer([]byte("")),
	)

	if err != nil {
		log.Printf(`GET %q resulted in %v`, url, err)
		return err
	}

	res, err := http.DefaultClient.Do(req)
	if err != nil {
		log.Printf(`GET %q resulted in %v`, url, err)
		return err
	}

	if err := json.NewDecoder(res.Body).Decode(response); err != nil {
		log.Printf(`GET %q resulted in %v`, url, err)
		return err
	}

	return nil
}

func (a *LDAPAuthService) doPostRequest(url string, request interface{}, response interface{}) error {
	jsonStr, err := json.Marshal(request)
	if err != nil {
		return err
	}

	req, err := http.NewRequest("POST", path.Join(a.Host, "ldap", url), bytes.NewBuffer(jsonStr))
	if err != nil {
		return err
	}

	req.Header.Set("Content-Type", "application/json")

	res, err := http.DefaultClient.Do(req)
	if err != nil {
		return err
	}

	return json.NewDecoder(res.Body).Decode(response)
}

func (a *LDAPAuthService) GetUser(username string) (*User, error) {
	var user ldapUser
	if err := a.doGetRequest(fmt.Sprintf("/user/%s", username), &user); err != nil {
		return nil, err
	}

	return user.AsUser(), nil
}

func (a *LDAPAuthService) GetUsers() ([]*User, error) {
	ldapUsers := []*ldapUser{}
	if err := a.doGetRequest(fmt.Sprintf("/users"), &ldapUsers); err != nil {
		return nil, err
	}

	users := make([]*User, len(ldapUsers))
	for i, u := range ldapUsers {
		users[i] = u.AsUser()
	}

	return users, nil
}

func (a *LDAPAuthService) GetSession(token string) (*Session, error) {
	var response Session
	if err := a.doGetRequest(fmt.Sprintf("/session/%s", token), &response); err != nil {
		return nil, err
	}

	return &response, nil
}

func (a *LDAPAuthService) Login(username, password string) (*Session, error) {
	reqBody := map[string]interface{}{
		"username": username,
		"password": password,
	}

	var response Session
	if err := a.doPostRequest(fmt.Sprintf("/login"), reqBody, &response); err != nil {
		return nil, err
	}

	return &response, nil
}