/**
 * Backend
 */

export interface Dump {
  id: string;
  title: string;
  description?: string;
  userId: string;
  createdAt: Date;
}

/**
 * Authentication
 */

export interface User {
  id: string;
  username: string;
  passwordHash: string;
  isAdmin: boolean;
  createdAt: Date;
}

export interface LoginUserRequest {
  username: string;
  password: string;
}

export interface RegisterUserRequest {
  username: string;
  password: string;
}

export interface UpdateUserRequest {
  username?: string;
  password?: string;
  isAdmin?: boolean;
}

export function isLoginUserRequest(obj: unknown): obj is LoginUserRequest {
  return !!obj && typeof obj === "object" &&
    "username" in obj && typeof obj.username === "string" &&
    "password" in obj && typeof obj.password === "string";
}

export function isRegisterUserRequest(
  obj: unknown,
): obj is RegisterUserRequest {
  return !!obj && typeof obj === "object" &&
    "username" in obj && typeof obj.username === "string" &&
    "password" in obj && typeof obj.password === "string";
}

export function isUpdateUserRequest(obj: unknown): obj is UpdateUserRequest {
  return !!obj && typeof obj === "object" &&
    (!("username" in obj) || typeof obj.username === "string") &&
    (!("password" in obj) || typeof obj.password === "string") &&
    (!("isAdmin" in obj) || typeof obj.isAdmin === "boolean");
}

export interface AuthResponse {
  token: string;
  user: User;
}

export interface AuthPayload {
  userId: string;
  username: string;
  isAdmin: boolean;
  exp: number;
}

export function isAuthPayload(obj: unknown): obj is AuthPayload {
  return !!obj &&
    typeof obj === "object" &&
    "userId" in obj && typeof obj.userId === "string" &&
    "username" in obj && typeof obj.username === "string" &&
    "isAdmin" in obj && typeof obj.isAdmin === "boolean" &&
    "exp" in obj && typeof obj.exp === "number";
}

/**
 * API
 */

export enum APIErrorCode {
  BAD_REQUEST = "BAD_REQUEST",
  NOT_FOUND = "NOT_FOUND",
  SERVER_ERROR = "SERVER_ERROR",
  TIMEOUT = "TIMEOUT",
  UNAUTHORIZED = "UNAUTHORIZED",
  VALIDATION_ERROR = "VALIDATION_ERROR",
}

export interface APIError {
  code: APIErrorCode;
  message: string;
}

export interface APISuccess<T> {
  success: true;
  data: T;
  error?: never;
}

export interface APIFailure {
  success: false;
  data?: never;
  error: APIError;
}

export type APIResponse<T> = APISuccess<T> | APIFailure;

export class APIException extends Error {
  readonly code: APIErrorCode;
  readonly status: number;

  constructor(code: APIErrorCode, status: number, message: string) {
    super(message);
    this.code = code;
    this.status = status;
  }
}

/**
 * Request DTOs
 */

export interface CreateDumpRequest {
  title: string;
  description?: string;
}

export function isCreateDumpRequest(obj: unknown): obj is CreateDumpRequest {
  return !!obj &&
    typeof obj === "object" &&
    "title" in obj && typeof obj.title === "string" &&
    (!("description" in obj) ||
      (typeof obj.description === "string" || obj.description === null));
}

export interface UpdateDumpRequest {
  title?: string;
  description?: string;
}

export function isUpdateDumpRequest(obj: unknown): obj is UpdateDumpRequest {
  return !!obj &&
    typeof obj === "object" &&
    (!("title" in obj) || typeof obj.title === "string") &&
    (!("description" in obj) ||
      (typeof obj.description === "string" || obj.description === null));
}