import pygame as pg

class Camera():
    def __init__(self):
        self.zoom = 2
        self.offset = pg.math.Vector2(0, 0)

    def world_to_screen(self, pos):
        return (
            int((pos[0] - self.offset.x) * self.zoom),
            int((pos[1] - self.offset.y) * self.zoom)
        )

    def screen_to_world(self, pos):
        return (
            pos[0] / self.zoom + self.offset.x,
            pos[1] / self.zoom + self.offset.y
        )

    def move(self, dx, dy):
        self.offset.x += dx
        self.offset.y += dy

    def change_zoom(self, amount):
        self.zoom += amount
        self.zoom = max(0.5, min(self.zoom, 4.0))
    

    def zoom_offset(self, screen_pos, zoom_factor):
        world_before = self.screen_to_world(screen_pos)

        self.change_zoom(zoom_factor)

        world_after = self.screen_to_world(screen_pos)

        self.offset.x += world_before[0] - world_after[0]
        self.offset.y += world_before[1] - world_after[1]