/**
 * Created by zhangsong on 2018/8/9.
 */

/**
 * Construct a token.
 *
 * Based on a JSON Web Token string, construct a token object. Optionally
 * if a `clientId` is provided, the token may be tested for roles with
 * `hasRole()`.
 *
 * @constructor
 *
 * @param {String} token The JSON Web Token formatted token string.
 * @param {String} clientId Optional clientId if this is an `access_token`.
 */

class Token {
  public token;
  public clientId;
  public header;
  public content;
  public signature;
  public signed;
  constructor(token, clientId?: string) {
    this.token = token;
    this.clientId = clientId;

    if (token) {
      try {
        const parts = token.split('.');
        this.header = JSON.parse(new Buffer(parts[0], 'base64').toString());
        this.content = JSON.parse(new Buffer(parts[1], 'base64').toString());
        this.signature = new Buffer(parts[2], 'base64');
        this.signed = parts[0] + '.' + parts[1];
      } catch (err) {
        this.content = {
          exp: 0,
        };
      }
    }
  }
  /**
   * Determine if this token is expired.
   * @return {boolean} `true` if it is expired, otherwise `false`.
   */
  public isExpired() {
    return (this.content.exp * 1000) < Date.now();
  }

  public hasRole(name) {
    if (!this.clientId) {
      return false;
    }

    const parts = name.split(':');
    if (parts.length === 1) {
      return this.hasApplicationRole(this.clientId, parts[0]);
    }

    if (parts[0] === 'realm') {
      return this.hasRealmRole(parts[1]);
    }

    return this.hasApplicationRole(parts[0], parts[1]);
  }

  public hasApplicationRole(appName, roleName) {
    const appRoles = this.content.resource_access[appName];

    if (!appRoles) {
      return false;
    }

    return (appRoles.roles.indexOf(roleName) >= 0);
  }

  public hasRealmRole(roleName) {
    // Make sure we have these properties before we check for a certain realm level role!
    // Without this we attempt to access an undefined property on token
    // for a user with no realm level roles.
    if (!this.content.realm_access || !this.content.realm_access.roles) {
      return false;
    }

    return (this.content.realm_access.roles.indexOf(roleName) >= 0);
  }

}

export default Token;