discordXP.js

const mongoose = require("mongoose");
const levels = require("./models/levels.js");
var mongoUrl;

class DiscordXp {

  /**
  * @param {string} [dbUrl] - A valid mongo database URI.
  */

  static async setURL(dbUrl) {
    if (!dbUrl) throw new TypeError("A database url was not provided.");
    mongoUrl = dbUrl;
    return mongoose.connect(dbUrl, {
      useNewUrlParser: true,
      useUnifiedTopology: true,
      useFindAndModify: false
    });
  }

  /**
  * @param {string} [userId] - Discord user id.
  * @param {string} [guildId] - Discord guild id.
  */

  static async createUser(userId, guildId) {
    if (!userId) throw new TypeError("An user id was not provided.");
    if (!guildId) throw new TypeError("A guild id was not provided.");

    const isUser = await levels.findOne({ userID: userId, guildID: guildId });
    if (isUser) return false;

    const newUser = new levels({
      userID: userId,
      guildID: guildId
    });

    await newUser.save().catch(e => console.log(`Failed to create user: ${e}`));

    return newUser;
  }

  /**
  * @param {string} [userId] - Discord user id.
  * @param {string} [guildId] - Discord guild id.
  */

  static async deleteUser(userId, guildId) {
    if (!userId) throw new TypeError("An user id was not provided.");
    if (!guildId) throw new TypeError("A guild id was not provided.");

    const user = await levels.findOne({ userID: userId, guildID: guildId });
    if (!user) return false;

    await levels.findOneAndDelete({ userID: userId, guildID: guildId }).catch(e => console.log(`Failed to delete user: ${e}`));

    return user;
  }

  /**
  * @param {string} [userId] - Discord user id.
  * @param {string} [guildId] - Discord guild id.
  * @param {number} [xp] - Amount of xp to append.
  */

  static async appendXp(userId, guildId, xp) {
    if (!userId) throw new TypeError("An user id was not provided.");
    if (!guildId) throw new TypeError("A guild id was not provided.");
    if (xp == 0 || !xp || isNaN(parseInt(xp))) throw new TypeError("An amount of xp was not provided/was invalid.");

    const user = await levels.findOne({ userID: userId, guildID: guildId });

    if (!user) {
      const newUser = new levels({
        userID: userId,
        guildID: guildId,
        xp: xp,
        level: Math.floor(0.1 * Math.sqrt(xp))
      });

      await newUser.save().catch(e => console.log(`Failed to save new user.`));

      return (Math.floor(0.1 * Math.sqrt(xp)) > 0);
    };

    user.xp += parseInt(xp, 10);
    user.level = Math.floor(0.1 * Math.sqrt(user.xp));
    user.lastUpdated = new Date();
 
    await user.save().catch(e => console.log(`Failed to append xp: ${e}`) );

    return (Math.floor(0.1 * Math.sqrt(user.xp -= xp)) < user.level);
  }

  /**
  * @param {string} [userId] - Discord user id.
  * @param {string} [guildId] - Discord guild id.
  * @param {number} [levels] - Amount of levels to append.
  */

  static async appendLevel(userId, guildId, levelss) {
    if (!userId) throw new TypeError("An user id was not provided.");
    if (!guildId) throw new TypeError("A guild id was not provided.");
    if (!levelss) throw new TypeError("An amount of levels was not provided.");

    const user = await levels.findOne({ userID: userId, guildID: guildId });
    if (!user) return false;
    
    user.level += parseInt(levelss, 10);
    user.xp = user.level * user.level * 100;
    user.lastUpdated = new Date();
 
    user.save().catch(e => console.log(`Failed to append level: ${e}`) );

    return user;
  }

  /**
  * @param {string} [userId] - Discord user id.
  * @param {string} [guildId] - Discord guild id.
  * @param {number} [xp] - Amount of xp to set.
  */

  static async setXp(userId, guildId, xp) {
    if (!userId) throw new TypeError("An user id was not provided.");
    if (!guildId) throw new TypeError("A guild id was not provided.");
    if (xp == 0 || !xp || isNaN(parseInt(xp))) throw new TypeError("An amount of xp was not provided/was invalid.");

    const user = await levels.findOne({ userID: userId, guildID: guildId });
    if (!user) return false;

    user.xp = xp;
    user.level = Math.floor(0.1 * Math.sqrt(user.xp));
    user.lastUpdated = new Date();
  
    user.save().catch(e => console.log(`Failed to set xp: ${e}`) );

    return user;
  }

  /**
  * @param {string} [userId] - Discord user id.
  * @param {string} [guildId] - Discord guild id.
  * @param {number} [level] - A level to set.
  */

  static async setLevel(userId, guildId, level) {
    if (!userId) throw new TypeError("An user id was not provided.");
    if (!guildId) throw new TypeError("A guild id was not provided.");
    if (!level) throw new TypeError("A level was not provided.");

    const user = await levels.findOne({ userID: userId, guildID: guildId });
    if (!user) return false;

    user.level = level;
    user.xp = level * level * 100;
    user.lastUpdated = new Date();
    
    user.save().catch(e => console.log(`Failed to set level: ${e}`) );

    return user;
  }

  /**
  * @param {string} [userId] - Discord user id.
  * @param {string} [guildId] - Discord guild id.
  */

  static async fetch(userId, guildId, fetchPosition = false) {
    if (!userId) throw new TypeError("An user id was not provided.");
    if (!guildId) throw new TypeError("A guild id was not provided.");

    const user = await levels.findOne({
      userID: userId,
      guildID: guildId
    });
    if (!user) return false;

    if (fetchPosition === true) {
      const leaderboard = await levels.find({
        guildID: guildId
      }).sort([['xp', 'descending']]).exec();

      user.position = leaderboard.findIndex(i => i.userID === userId) + 1;
    }

    
    /* To be used with canvacord or displaying xp in a pretier fashion, with each level the cleanXp stats from 0 and goes until cleanNextLevelXp when user levels up and gets back to 0 then the cleanNextLevelXp is re-calculated */
    user.cleanXp = user.xp - this.xpFor(user.level);
    user.cleanNextLevelXp = this.xpFor(user.level + 1) - this.xpFor(user.level);
    
    return user;
  }

  /**
  * @param {string} [userId] - Discord user id.
  * @param {string} [guildId] - Discord guild id.
  * @param {number} [xp] - Amount of xp to subtract.
  */

  static async subtractXp(userId, guildId, xp) {
    if (!userId) throw new TypeError("An user id was not provided.");
    if (!guildId) throw new TypeError("A guild id was not provided.");
    if (xp == 0 || !xp || isNaN(parseInt(xp))) throw new TypeError("An amount of xp was not provided/was invalid.");

    const user = await levels.findOne({ userID: userId, guildID: guildId });
    if (!user) return false;

    user.xp -= xp;
    user.level = Math.floor(0.1 * Math.sqrt(user.xp));
    user.lastUpdated = new Date();
   
    user.save().catch(e => console.log(`Failed to subtract xp: ${e}`) );

    return user;
  }

  /**
  * @param {string} [userId] - Discord user id.
  * @param {string} [guildId] - Discord guild id.
  * @param {number} [levels] - Amount of levels to subtract.
  */

  static async subtractLevel(userId, guildId, levelss) {
    if (!userId) throw new TypeError("An user id was not provided.");
    if (!guildId) throw new TypeError("A guild id was not provided.");
    if (!levelss) throw new TypeError("An amount of levels was not provided.");

    const user = await levels.findOne({ userID: userId, guildID: guildId });
    if (!user) return false;

    user.level -= levelss;
    user.xp = user.level * user.level * 100;
    user.lastUpdated = new Date();
    
    user.save().catch(e => console.log(`Failed to subtract levels: ${e}`) );

    return user;
  }

  /**
  * @param {string} [guildId] - Discord guild id.
  * @param {number} [limit] - Amount of maximum enteries to return.
  */


  static async fetchLeaderboard(guildId, limit) {
    if (!guildId) throw new TypeError("A guild id was not provided.");
    if (!limit) throw new TypeError("A limit was not provided.");

    var users = await levels.find({ guildID: guildId }).sort([['xp', 'descending']]).exec();

    return users.slice(0, limit);
  }

  /**
  * @param {string} [client] - Your Discord.CLient.
  * @param {array} [leaderboard] - The output from 'fetchLeaderboard' function.
  */

  static async computeLeaderboard(client, leaderboard, fetchUsers = false) {
    if (!client) throw new TypeError("A client was not provided.");
    if (!leaderboard) throw new TypeError("A leaderboard id was not provided.");

    if (leaderboard.length < 1) return [];

    const computedArray = [];

    if (fetchUsers) {
      for (const key of leaderboard) {
        const user = await client.users.fetch(key.userID) || { username: "Unknown", discriminator: "0000" };
        computedArray.push({
          guildID: key.guildID,
          userID: key.userID,
          xp: key.xp,
          level: key.level,
          position: (leaderboard.findIndex(i => i.guildID === key.guildID && i.userID === key.userID) + 1),
          username: user.username,
          discriminator: user.discriminator
        });
      }
    } else {
      leaderboard.map(key => computedArray.push({
        guildID: key.guildID,
        userID: key.userID,
        xp: key.xp,
        level: key.level,
        position: (leaderboard.findIndex(i => i.guildID === key.guildID && i.userID === key.userID) + 1),
        username: client.users.cache.get(key.userID) ? client.users.cache.get(key.userID).username : "Unknown",
        discriminator: client.users.cache.get(key.userID) ? client.users.cache.get(key.userID).discriminator : "0000"
      }));
    }

    return computedArray;
  }
  
  /*
  * @param {number} [targetLevel] - Xp required to reach that level.
  */
  static xpFor (targetLevel) {
    if (isNaN(targetLevel) || isNaN(parseInt(targetLevel, 10))) throw new TypeError("Target level should be a valid number.");
    if (isNaN(targetLevel)) targetLevel = parseInt(targetLevel, 10);
    if (targetLevel < 0) throw new RangeError("Target level should be a positive number.");
    return targetLevel * targetLevel * 100;
  }

  /**
  * @param {string} [guildId] - Discord guild id.
  */

   static async deleteGuild(guildId) {
    if (!guildId) throw new TypeError("A guild id was not provided.");

    const guild = await levels.findOne({ guildID: guildId });
    if (!guild) return false;

    await levels.deleteMany({ guildID: guildId }).catch(e => console.log(`Failed to delete guild: ${e}`));

    return guild;
  }
}

module.exports = DiscordXp;