text: const { URLSearchParams } = require('url');
  const { BearerClient } = require('./BearerClient.js');
  const { Permissions } = require('./Permissions.js');
  const { State } = require('./State.js');
  const { oauth } = require('../api/index.js');
  const { verifyScopes } = require('../util/verifyScopes.js');
  const { randomString } = require('../util/randomString.js');
  const { base, endpoints } = require('../static/api.js');
  
  class Authorization {
      constructor(options = {}) {
          this.client = options.client;
          this.state = options.state;
          this.verifyScopes = options.verifyScopes;
  
          this.scopes = options.scopes;
          this.redirect = options.redirect;
          this.returnUrl = options.returnUrl;
          this.type = options.type;
  
          this.permissions = options.permissions;
          this.guild = options.guild;
          this.channel = options.channel;
      }
  
      generate(returnUrl = this.returnUrl, state = randomString(20)) {
          state = new State({ state: this.state ? state : null, returnUrl });
  
          const params = new URLSearchParams();
  
          params.append('client_id', this.client.clientId);
          params.append('scope', this.scopes.join(' '));
          if (state) params.append('state', state);
  
          if (this.redirect) params.append('redirect_uri', this.redirect);
          if (this.type) params.append('response_type', this.type);
  
          if (this.permissions) params.append('permissions', this.permissions);
          if (this.guild) params.append('guild_id', this.guild);
          if (this.channel) params.append('channel_id', this.channel);
  
          const url = `${base}${endpoints.oauth.base}${endpoints.oauth.authorize}?${params.toString()}`;
  
          return { url, state: state.state };
      }
  
      async callback(params, state = null) {
          params = new URLSearchParams(params);
          if (params.has('error')) return { error: true, message: params.get('error'), redirect: '/' };
          if (!params.has('code')) return { error: true, message: 'Missing code' };
  
          const cbState = params.has('state') ? new State(params.get('state')) : null;
          if (this.state && (!cbState || cbState.state !== state)) return { error: true, message: 'Invalid or missing state', redirect: cbState ? cbState.return : '/' };
  
          const response = {
              error: false,
              token: null,
              bearer: null,
              guildId: null,
              permissions: null,
              redirect: cbState ? cbState.return : '/'
          };
  
          if (params.has('guild_id')) response.guildId = params.get('guild_id');
          if (params.has('permissions')) response.permissions = new Permissions(params.get('permissions'), false, false);
  
          try {
              response.token = await oauth.token({
                  id: this.client.clientId,
                  secret: this.client.clientSecret,
                  grant: 'authorization_code',
                  code: params.get('code'),
                  redirect: this.redirect,
                  scopes: this.scopes
              });
  
              if (this.verifyScopes && !verifyScopes(this.scopes, response.token.scopes)) return { error: true, error: 'Scopes do not match', redirect: cbState ? cbState.return : null };
          }
          catch (e) {
              return { error: true, error: 'Error getting access token', redirect: cbState ? cbState.return : null };
          }
  
          response.bearer = new BearerClient(this, response.token.accessToken, response.token.refreshToken);
          await response.bearer.fetchData();
  
          return response;
      }
  }
  
  module.exports = { Authorization };