using System;
using System.Collections;
using UnityEngine;
using UnityEngine.Networking;

public class LoginHttps : MonoBehaviour {
    public void Login(string userName, string password, string url, Action onSuccess, Action onFailed) {
        // TODO: do somethings to validate user name & password from client
        //...
        StartCoroutine(IELogin(userName, password, url, onSuccess, onFailed));
    }

    IEnumerator IELogin(string userName, string password, string url, Action onSuccess, Action onFailed) {
        WWWForm form = new WWWForm();
        form.AddField("uid", userName);
        form.AddField("pass", password);

        using (UnityWebRequest www = UnityWebRequest.Post(url, form)) {
            yield return www.SendWebRequest();

            if (www.isDone) {
                string response = www.downloadHandler.text; // response is a json string like: {code:0,err:"wrong password"}
                if (!string.IsNullOrEmpty(response)) {
                    ResponseData result = JsonUtility.FromJson(response);
                    if (result != null) {
                        if (result.code == 1) {
                            Debug.Log("Login Successfully.");
                            onSuccess?.Invoke();
                        }
                        else {
                            Debug.LogError($"Login Failure: {result.err}");
                            onFailed?.Invoke();
                        }
                    }
                }
                else {
                    Debug.LogError("Something wrong from response, check your backend!");
                    onFailed?.Invoke();
                }
            }
            else {
                Debug.LogError(www.error); // Network error or something wrong which can not post to url.
                onFailed?.Invoke();
            }
        }
    }

    [System.Serializable]
    class ResponseData {
        public int code; // 0: Login Failed, 1: Login Success
        public string err; // Such as: Username is not exist, Wrong password...
    }
}