Levelling system based on arithmetic linear progression

levels.py

import math

class Levels:
    def __init__(self, xp_per_message, multiplier):
        self.threshold = round(multiplier/5, 0)
        # Multiplier would previously use large numbers
        # so multiplying by 10 would make input numbers
        # smaller by default, change this if you dont
        # like that
        self.multiplier = multiplier * 10
        self.xp_per_message = xp_per_message

    def current_level(self, xp):
        """The current level based on the xp amount"""
        # 'math.floor' used to round levels down for obvious reasons
        return math.floor((1+math.sqrt(1 + self.multiplier * xp / 50))/2)
    
    def level_xp(self, level):
        """The xp required to pass the specified level"""
        return ((level**self.threshold - level) * self.multiplier)/2

    def messages_for_level(self, level):
        """The messages required for the specified level"""
        l_xp = self.level_xp(level=level)
        return l_xp / self.xp_per_message

usage.py

# Configuration (can merge into init line, just useful for external config options)
xp_per_message = 10
multiplier = 15

# Initialize the class
levels = Levels(
    xp_per_message=xp_per_message,
    multiplier=multiplier
)

# Print out the first 4 levels along with their respective progression values
for level in range(1,5):
    print(f"[Level {level}]")
    print(f"- {levels.level_exp(level)} XP")
    print(f"- {levels.messages_for_level(level)} messages")
    print("\n")