/*
 * Copyright (C) 2022 Savoir-faire Linux Inc.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation; either version 3 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public
 * License along with this program.  If not, see
 * <https://www.gnu.org/licenses/>.
 */
import argon2 from 'argon2';
import { Router } from 'express';
import asyncHandler from 'express-async-handler';
import { ParamsDictionary, Request } from 'express-serve-static-core';
import { AccessToken, AccountDetails, HttpStatusCode, UserCredentials } from 'jami-web-common';
import { Container } from 'typedi';

import { Jamid } from '../jamid/jamid.js';
import { NameRegistrationEndedState, RegistrationState } from '../jamid/state-enums.js';
import { Accounts } from '../storage/accounts.js';
import { signJwt } from '../utils/jwt.js';

const jamid = Container.get(Jamid);
const accounts = Container.get(Accounts);

export const authRouter = Router();

authRouter.post(
  '/new-account',
  asyncHandler(async (req: Request<ParamsDictionary, string, Partial<UserCredentials>>, res) => {
    const { username, password, isJams } = req.body;
    if (username === undefined || password === undefined) {
      res.status(HttpStatusCode.BadRequest).send('Missing username or password in body');
      return;
    }

    const isAccountAlreadyCreated = accounts.get(username, isJams) !== undefined;
    if (isAccountAlreadyCreated) {
      res.status(HttpStatusCode.Conflict).send('Username already exists locally');
      return;
    }

    if (password === '') {
      res.status(HttpStatusCode.BadRequest).send('Password may not be empty');
      return;
    }

    const hashedPassword = await argon2.hash(password, { type: argon2.argon2id });

    const accountDetails: Partial<AccountDetails> = {
      // TODO: Enable encrypted archives
      // 'Account.archivePassword': password
    };
    if (isJams) {
      accountDetails['Account.managerUri'] = 'https://jams.savoirfairelinux.com/';
      accountDetails['Account.managerUsername'] = username;
    }
    const { accountId, state } = await jamid.addAccount(accountDetails);

    if (isJams) {
      if (state === RegistrationState.ErrorGeneric) {
        jamid.removeAccount(accountId);
        res.status(HttpStatusCode.Unauthorized).send('Invalid JAMS credentials');
        return;
      }
    } else {
      const state = await jamid.registerUsername(accountId, username, '');
      if (state !== NameRegistrationEndedState.Success) {
        jamid.removeAccount(accountId);
        switch (state) {
          case NameRegistrationEndedState.InvalidName:
            res.status(HttpStatusCode.BadRequest).send('Invalid username or password');
            break;
          case NameRegistrationEndedState.AlreadyTaken:
            res.status(HttpStatusCode.Conflict).send('Username already exists');
            break;
          default:
            throw new Error(`Unhandled state ${state}`);
        }
        return;
      }
    }

    accounts.set(username, hashedPassword, isJams);
    await accounts.save();

    res.sendStatus(HttpStatusCode.Created);
  })
);

authRouter.post(
  '/login',
  asyncHandler(async (req: Request<ParamsDictionary, AccessToken | string, Partial<UserCredentials>>, res) => {
    const { username, password, isJams } = req.body;
    if (username === undefined || password === undefined) {
      res.status(HttpStatusCode.BadRequest).send('Missing username or password in body');
      return;
    }

    // Check if the account is stored on this daemon instance
    const accountId = jamid.getAccountIdFromUsername(username);
    if (accountId === undefined) {
      res.status(HttpStatusCode.Unauthorized).send('Username not found');
      return;
    }

    const hashedPassword = accounts.get(username, isJams);
    if (hashedPassword === undefined) {
      res
        .status(HttpStatusCode.Unauthorized)
        .send('Password not found (the account does not have a password set on the server)');
      return;
    }

    const isPasswordVerified = await argon2.verify(hashedPassword, password);
    if (!isPasswordVerified) {
      res.status(HttpStatusCode.Unauthorized).send('Incorrect password');
      return;
    }

    const jwt = await signJwt(accountId);
    res.status(HttpStatusCode.Ok).send({ accessToken: jwt });
  })
);