/* eslint-disable no-use-before-define */

const debug = require('debug')('growi:models:user');
const logger = require('@alias/logger')('growi:models:user');
const mongoose = require('mongoose');
const mongoosePaginate = require('mongoose-paginate-v2');
const path = require('path');
const uniqueValidator = require('mongoose-unique-validator');
const md5 = require('md5');

const ObjectId = mongoose.Schema.Types.ObjectId;
const crypto = require('crypto');

const { listLocaleIds, migrateDeprecatedLocaleId } = require('@commons/util/locale-utils');

const { omitInsecureAttributes } = require('./serializers/user-serializer');

module.exports = function(crowi) {
  const STATUS_REGISTERED = 1;
  const STATUS_ACTIVE = 2;
  const STATUS_SUSPENDED = 3;
  const STATUS_DELETED = 4;
  const STATUS_INVITED = 5;
  const USER_FIELDS_EXCEPT_CONFIDENTIAL = '_id image isEmailPublished isGravatarEnabled googleId name username email introduction'
  + ' status lang createdAt lastLoginAt admin imageUrlCached';

  const PAGE_ITEMS = 50;

  let userEvent;

  // init event
  if (crowi != null) {
    userEvent = crowi.event('user');
    userEvent.on('activated', userEvent.onActivated);
  }

  const userSchema = new mongoose.Schema({
    userId: String,
    image: String,
    imageAttachment: { type: ObjectId, ref: 'Attachment' },
    imageUrlCached: String,
    isGravatarEnabled: { type: Boolean, default: false },
    isEmailPublished: { type: Boolean, default: true },
    googleId: String,
    name: { type: String },
    username: { type: String, required: true, unique: true },
    email: { type: String, unique: true, sparse: true },
    // === Crowi settings
    // username: { type: String, index: true },
    // email: { type: String, required: true, index: true },
    // === crowi-plus (>= 2.1.0, <2.3.0) settings
    // email: { type: String, required: true, unique: true },
    introduction: String,
    password: String,
    apiToken: { type: String, index: true },
    lang: {
      type: String,
      enum: listLocaleIds(),
      default: 'en_US',
    },
    status: {
      type: Number, required: true, default: STATUS_ACTIVE, index: true,
    },
    createdAt: { type: Date, default: Date.now },
    lastLoginAt: { type: Date },
    admin: { type: Boolean, default: 0, index: true },
  }, {
    toObject: {
      transform: (doc, ret, opt) => {
        return omitInsecureAttributes(ret);
      },
    },
  });
  // eslint-disable-next-line prefer-arrow-callback
  userSchema.pre('validate', function() {
    this.lang = migrateDeprecatedLocaleId(this.lang);
  });
  userSchema.plugin(mongoosePaginate);
  userSchema.plugin(uniqueValidator);

  function validateCrowi() {
    if (crowi == null) {
      throw new Error('"crowi" is null. Init User model with "crowi" argument first.');
    }
  }

  function decideUserStatusOnRegistration() {
    validateCrowi();

    const { configManager, aclService } = crowi;

    const isInstalled = configManager.getConfig('crowi', 'app:installed');
    if (!isInstalled) {
      return STATUS_ACTIVE; // is this ok?
    }

    // status decided depends on registrationMode
    const registrationMode = configManager.getConfig('crowi', 'security:registrationMode');
    switch (registrationMode) {
      case aclService.labels.SECURITY_REGISTRATION_MODE_OPEN:
        return STATUS_ACTIVE;
      case aclService.labels.SECURITY_REGISTRATION_MODE_RESTRICTED:
      case aclService.labels.SECURITY_REGISTRATION_MODE_CLOSED: // 一応
        return STATUS_REGISTERED;
      default:
        return STATUS_ACTIVE; // どっちにすんのがいいんだろうな
    }
  }

  function generateRandomEmail() {
    const randomstr = generateRandomTempPassword();
    return `change-it-${randomstr}@example.com`;
  }

  function generateRandomTempPassword() {
    const chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789!=-_';
    let password = '';
    const len = 12;

    for (let i = 0; i < len; i++) {
      const randomPoz = Math.floor(Math.random() * chars.length);
      password += chars.substring(randomPoz, randomPoz + 1);
    }

    return password;
  }

  function generatePassword(password) {
    validateCrowi();

    const hasher = crypto.createHash('sha256');
    hasher.update(crowi.env.PASSWORD_SEED + password);

    return hasher.digest('hex');
  }

  function generateApiToken(user) {
    const hasher = crypto.createHash('sha256');
    hasher.update((new Date()).getTime() + user._id);

    return hasher.digest('base64');
  }

  userSchema.methods.isPasswordSet = function() {
    if (this.password) {
      return true;
    }
    return false;
  };

  userSchema.methods.isPasswordValid = function(password) {
    return this.password === generatePassword(password);
  };

  userSchema.methods.setPassword = function(password) {
    this.password = generatePassword(password);
    return this;
  };

  userSchema.methods.isEmailSet = function() {
    if (this.email) {
      return true;
    }
    return false;
  };

  userSchema.methods.updateLastLoginAt = function(lastLoginAt, callback) {
    this.lastLoginAt = lastLoginAt;
    this.save((err, userData) => {
      return callback(err, userData);
    });
  };

  userSchema.methods.updateIsGravatarEnabled = async function(isGravatarEnabled) {
    this.isGravatarEnabled = isGravatarEnabled;
    await this.updateImageUrlCached();
    const userData = await this.save();
    return userData;
  };

  userSchema.methods.updatePassword = async function(password) {
    this.setPassword(password);
    const userData = await this.save();
    return userData;
  };

  userSchema.methods.canDeleteCompletely = function(creatorId) {
    const pageCompleteDeletionAuthority = crowi.configManager.getConfig('crowi', 'security:pageCompleteDeletionAuthority');
    if (this.admin) {
      return true;
    }
    if (pageCompleteDeletionAuthority === 'anyOne' || pageCompleteDeletionAuthority == null) {
      return true;
    }
    if (pageCompleteDeletionAuthority === 'adminAndAuthor') {
      return (this._id.equals(creatorId));
    }

    return false;
  };

  userSchema.methods.updateApiToken = async function() {
    const self = this;

    self.apiToken = generateApiToken(this);
    const userData = await self.save();
    return userData;
  };

  // TODO: create UserService and transplant this method because image uploading depends on AttachmentService
  userSchema.methods.updateImage = async function(attachment) {
    this.imageAttachment = attachment;
    await this.updateImageUrlCached();
    return this.save();
  };

  // TODO: create UserService and transplant this method because image deletion depends on AttachmentService
  userSchema.methods.deleteImage = async function() {
    validateCrowi();

    // the 'image' field became DEPRECATED in v3.3.8
    this.image = undefined;

    if (this.imageAttachment != null) {
      const { attachmentService } = crowi;
      attachmentService.removeAttachment(this.imageAttachment._id);
    }

    this.imageAttachment = undefined;
    this.updateImageUrlCached();
    return this.save();
  };

  userSchema.methods.updateImageUrlCached = async function() {
    this.imageUrlCached = await this.generateImageUrlCached();
  };

  userSchema.methods.generateImageUrlCached = async function() {
    if (this.isGravatarEnabled) {
      const email = this.email || '';
      const hash = md5(email.trim().toLowerCase());
      return `https://gravatar.com/avatar/${hash}`;
    }
    if (this.image != null) {
      return this.image;
    }
    if (this.imageAttachment != null && this.imageAttachment._id != null) {
      const Attachment = crowi.model('Attachment');
      const imageAttachment = await Attachment.findById(this.imageAttachment);
      return imageAttachment.filePathProxied;
    }
    return '/images/icons/user.svg';
  };

  userSchema.methods.updateGoogleId = function(googleId, callback) {
    this.googleId = googleId;
    this.save((err, userData) => {
      return callback(err, userData);
    });
  };

  userSchema.methods.deleteGoogleId = function(callback) {
    return this.updateGoogleId(null, callback);
  };

  userSchema.methods.activateInvitedUser = async function(username, name, password) {
    this.setPassword(password);
    this.name = name;
    this.username = username;
    this.status = STATUS_ACTIVE;

    this.save((err, userData) => {
      userEvent.emit('activated', userData);
      if (err) {
        throw new Error(err);
      }
      return userData;
    });
  };

  userSchema.methods.removeFromAdmin = async function() {
    debug('Remove from admin', this);
    this.admin = 0;
    return this.save();
  };

  userSchema.methods.makeAdmin = async function() {
    debug('Admin', this);
    this.admin = 1;
    return this.save();
  };

  userSchema.methods.asyncMakeAdmin = async function(callback) {
    this.admin = 1;
    return this.save();
  };

  userSchema.methods.statusActivate = async function() {
    debug('Activate User', this);
    this.status = STATUS_ACTIVE;
    const userData = await this.save();
    return userEvent.emit('activated', userData);
  };

  userSchema.methods.statusSuspend = async function() {
    debug('Suspend User', this);
    this.status = STATUS_SUSPENDED;
    if (this.email === undefined || this.email === null) { // migrate old data
      this.email = '-';
    }
    if (this.name === undefined || this.name === null) { // migrate old data
      this.name = `-${Date.now()}`;
    }
    if (this.username === undefined || this.usename === null) { // migrate old data
      this.username = '-';
    }
    return this.save();
  };

  userSchema.methods.statusDelete = async function() {
    debug('Delete User', this);

    const now = new Date();
    const deletedLabel = `deleted_at_${now.getTime()}`;

    this.status = STATUS_DELETED;
    this.username = deletedLabel;
    this.password = '';
    this.name = '';
    this.email = `${deletedLabel}@deleted`;
    this.googleId = null;
    this.isGravatarEnabled = false;
    this.image = null;
    return this.save();
  };

  userSchema.methods.updateGoogleId = function(googleId, callback) {
    this.googleId = googleId;
    this.save((err, userData) => {
      return callback(err, userData);
    });
  };

  userSchema.statics.getUserStatusLabels = function() {
    const userStatus = {};
    userStatus[STATUS_REGISTERED] = 'Approval Pending';
    userStatus[STATUS_ACTIVE] = 'Active';
    userStatus[STATUS_SUSPENDED] = 'Suspended';
    userStatus[STATUS_DELETED] = 'Deleted';
    userStatus[STATUS_INVITED] = 'Invited';

    return userStatus;
  };

  userSchema.statics.isEmailValid = function(email, callback) {
    validateCrowi();

    const whitelist = crowi.configManager.getConfig('crowi', 'security:registrationWhiteList');

    if (Array.isArray(whitelist) && whitelist.length > 0) {
      return whitelist.some((allowedEmail) => {
        const re = new RegExp(`${allowedEmail}$`);
        return re.test(email);
      });
    }

    return true;
  };

  userSchema.statics.findUsers = function(options, callback) {
    const sort = options.sort || { status: 1, createdAt: 1 };

    this.find()
      .sort(sort)
      .skip(options.skip || 0)
      .limit(options.limit || 21)
      .exec((err, userData) => {
        callback(err, userData);
      });
  };

  userSchema.statics.findAllUsers = function(option) {
    // eslint-disable-next-line no-param-reassign
    option = option || {};

    const sort = option.sort || { createdAt: -1 };
    const fields = option.fields || {};

    let status = option.status || [STATUS_ACTIVE, STATUS_SUSPENDED];
    if (!Array.isArray(status)) {
      status = [status];
    }

    return this.find()
      .or(status.map((s) => { return { status: s } }))
      .select(fields)
      .sort(sort);
  };

  userSchema.statics.findUsersByIds = function(ids, option) {
    // eslint-disable-next-line no-param-reassign
    option = option || {};

    const sort = option.sort || { createdAt: -1 };
    const status = option.status || STATUS_ACTIVE;
    const fields = option.fields || {};

    return this.find({ _id: { $in: ids }, status })
      .select(fields)
      .sort(sort);
  };

  userSchema.statics.findAdmins = async function() {
    return this.find({ admin: true });
  };

  userSchema.statics.findUserByUsername = function(username) {
    if (username == null) {
      return Promise.resolve(null);
    }
    return this.findOne({ username });
  };

  userSchema.statics.findUserByApiToken = function(apiToken) {
    if (apiToken == null) {
      return Promise.resolve(null);
    }
    return this.findOne({ apiToken });
  };

  userSchema.statics.findUserByGoogleId = function(googleId, callback) {
    if (googleId == null) {
      callback(null, null);
    }
    this.findOne({ googleId }, (err, userData) => {
      callback(err, userData);
    });
  };

  userSchema.statics.findUserByUsernameOrEmail = function(usernameOrEmail, password, callback) {
    this.findOne()
      .or([
        { username: usernameOrEmail },
        { email: usernameOrEmail },
      ])
      .exec((err, userData) => {
        callback(err, userData);
      });
  };

  userSchema.statics.findUserByEmailAndPassword = function(email, password, callback) {
    const hashedPassword = generatePassword(password);
    this.findOne({ email, password: hashedPassword }, (err, userData) => {
      callback(err, userData);
    });
  };

  userSchema.statics.isUserCountExceedsUpperLimit = async function() {
    const { configManager } = crowi;

    const userUpperLimit = configManager.getConfig('crowi', 'security:userUpperLimit');

    const activeUsers = await this.countListByStatus(STATUS_ACTIVE);
    if (userUpperLimit <= activeUsers) {
      return true;
    }

    return false;
  };

  userSchema.statics.countListByStatus = async function(status) {
    const User = this;
    const conditions = { status };

    // TODO count は非推奨。mongoose のバージョンアップ後に countDocuments に変更する。
    return User.count(conditions);
  };

  userSchema.statics.isRegisterableUsername = async function(username) {
    let usernameUsable = true;

    const userData = await this.findOne({ username });
    if (userData) {
      usernameUsable = false;
    }
    return usernameUsable;
  };

  userSchema.statics.isRegisterable = function(email, username, callback) {
    const User = this;
    let emailUsable = true;
    let usernameUsable = true;

    // username check
    this.findOne({ username }, (err, userData) => {
      if (userData) {
        usernameUsable = false;
      }

      // email check
      User.findOne({ email }, (err, userData) => {
        if (userData) {
          emailUsable = false;
        }

        if (!emailUsable || !usernameUsable) {
          return callback(false, { email: emailUsable, username: usernameUsable });
        }

        return callback(true, {});
      });
    });
  };

  userSchema.statics.resetPasswordByRandomString = async function(id) {
    const user = await this.findById(id);

    if (!user) {
      throw new Error('User not found');
    }

    const newPassword = generateRandomTempPassword();
    user.setPassword(newPassword);
    await user.save();

    return newPassword;
  };

  userSchema.statics.createUserByEmail = async function(email) {
    const configManager = crowi.configManager;

    const User = this;
    const newUser = new User();

    /* eslint-disable newline-per-chained-call */
    const tmpUsername = `temp_${Math.random().toString(36).slice(-16)}`;
    const password = Math.random().toString(36).slice(-16);
    /* eslint-enable newline-per-chained-call */

    newUser.username = tmpUsername;
    newUser.email = email;
    newUser.setPassword(password);
    newUser.createdAt = Date.now();
    newUser.status = STATUS_INVITED;

    const globalLang = configManager.getConfig('crowi', 'app:globalLang');
    if (globalLang != null) {
      newUser.lang = globalLang;
    }

    try {
      const newUserData = await newUser.save();
      return {
        email,
        password,
        user: newUserData,
      };
    }
    catch (err) {
      return {
        email,
      };
    }
  };

  userSchema.statics.createUsersByEmailList = async function(emailList) {
    const User = this;

    // check exists and get list of try to create
    const existingUserList = await User.find({ email: { $in: emailList }, userStatus: { $ne: STATUS_DELETED } });
    const existingEmailList = existingUserList.map((user) => { return user.email });
    const creationEmailList = emailList.filter((email) => { return existingEmailList.indexOf(email) === -1 });

    const createdUserList = [];
    await Promise.all(creationEmailList.map(async(email) => {
      const createdEmail = await this.createUserByEmail(email);
      createdUserList.push(createdEmail);
    }));

    return { existingEmailList, createdUserList };
  };

  userSchema.statics.sendEmailbyUserList = async function(userList) {
    const { appService, mailService } = crowi;
    const appTitle = appService.getAppTitle();

    await Promise.all(userList.map(async(user) => {
      if (user.password == null) {
        return;
      }

      try {
        return mailService.send({
          to: user.email,
          subject: `Invitation to ${appTitle}`,
          template: path.join(crowi.localeDir, 'en_US/admin/userInvitation.txt'),
          vars: {
            email: user.email,
            password: user.password,
            url: crowi.appService.getSiteUrl(),
            appTitle,
          },
        });
      }
      catch (err) {
        return debug('fail to send email: ', err);
      }
    }));

  };

  userSchema.statics.createUsersByInvitation = async function(emailList, toSendEmail) {
    validateCrowi();

    if (!Array.isArray(emailList)) {
      debug('emailList is not array');
    }

    const afterWorkEmailList = await this.createUsersByEmailList(emailList);

    if (toSendEmail) {
      await this.sendEmailbyUserList(afterWorkEmailList.createdUserList);
    }

    return afterWorkEmailList;
  };

  userSchema.statics.createUserByEmailAndPasswordAndStatus = async function(name, username, email, password, lang, status, callback) {
    const User = this;
    const newUser = new User();

    // check user upper limit
    const isUserCountExceedsUpperLimit = await User.isUserCountExceedsUpperLimit();
    if (isUserCountExceedsUpperLimit) {
      const err = new UserUpperLimitException();
      return callback(err);
    }

    // check email duplication because email must be unique
    const count = await this.count({ email });
    if (count > 0) {
      // eslint-disable-next-line no-param-reassign
      email = generateRandomEmail();
    }

    newUser.name = name;
    newUser.username = username;
    newUser.email = email;
    if (password != null) {
      newUser.setPassword(password);
    }

    const configManager = crowi.configManager;
    const globalLang = configManager.getConfig('crowi', 'app:globalLang');
    if (globalLang != null) {
      newUser.lang = globalLang;
    }

    if (lang != null) {
      newUser.lang = lang;
    }
    newUser.createdAt = Date.now();
    newUser.status = status || decideUserStatusOnRegistration();

    newUser.save((err, userData) => {
      if (err) {
        logger.error('createUserByEmailAndPasswordAndStatus failed: ', err);
        return callback(err);
      }

      if (userData.status === STATUS_ACTIVE) {
        userEvent.emit('activated', userData);
      }
      return callback(err, userData);
    });
  };

  /**
   * A wrapper function of createUserByEmailAndPasswordAndStatus with callback
   *
   */
  userSchema.statics.createUserByEmailAndPassword = function(name, username, email, password, lang, callback) {
    this.createUserByEmailAndPasswordAndStatus(name, username, email, password, lang, undefined, callback);
  };

  /**
   * A wrapper function of createUserByEmailAndPasswordAndStatus
   *
   * @return {Promise<User>}
   */
  userSchema.statics.createUser = function(name, username, email, password, lang, status) {
    const User = this;

    return new Promise((resolve, reject) => {
      User.createUserByEmailAndPasswordAndStatus(name, username, email, password, lang, status, (err, userData) => {
        if (err) {
          return reject(err);
        }
        return resolve(userData);
      });
    });
  };

  userSchema.statics.getUsernameByPath = function(path) {
    let username = null;
    const match = path.match(/^\/user\/([^/]+)\/?/);
    if (match) {
      username = match[1];
    }

    return username;
  };

  class UserUpperLimitException {

    constructor() {
      this.name = this.constructor.name;
    }

  }

  userSchema.statics.STATUS_REGISTERED = STATUS_REGISTERED;
  userSchema.statics.STATUS_ACTIVE = STATUS_ACTIVE;
  userSchema.statics.STATUS_SUSPENDED = STATUS_SUSPENDED;
  userSchema.statics.STATUS_DELETED = STATUS_DELETED;
  userSchema.statics.STATUS_INVITED = STATUS_INVITED;
  userSchema.statics.USER_FIELDS_EXCEPT_CONFIDENTIAL = USER_FIELDS_EXCEPT_CONFIDENTIAL;
  userSchema.statics.PAGE_ITEMS = PAGE_ITEMS;

  return mongoose.model('User', userSchema);
};