player_character_controller.gd

extends CharacterBody3D

class_name PlayerCharacterController


##The script to handle the character's movement.
##It governs everything in relation on player physics and input handling.


##Export properties for anything we need to tune the value for.
##We want to avoid hardcoding as much as possible

@export_category("Ground Movement Properties")
@export var max_speed : float ## Max speed the player can achive horrizontally.
@export var acceleration : float ## The force applied to the player as they accelerate along the ground.
@export var friction : float ## The force applied to the player as they come to a stop.

@export_category("Air Movement Properties")
@export_range(1.0, 500.0, 0.1) var jump_force : float = 10.0 ## The force applied to the player when they initally jump.
@export_range(1.0, 100.0, 0.1) var down_force : float = 1.0 ## A downwards force applied to the player's jump as they are rising to create a proper parabolic arc
@export_range(1.0, 500.0, 0.1) var gravity := 17.0 ##constant force of gravity applied to falling player
@export_range(1.0, 1000.0, 0.1) var terminal_velocity := 20.0 ##player's max falling speed
var _intial_jump_force : float ##proxy varible to store jump force as it decreases over the course of the arc. Allows it to be reset later.
var _jumping : bool = false

func _ready() -> void:
    _intial_jump_force = jump_force

func _physics_process(delta: float) -> void:
    ###Player movement physics

    ##How the player moves on the ground
    var move_input_vector : Vector2 = Input.get_vector("move_left", "move_right", "move_up", "move_down")


    #input_vector is a vector2, we will need to conver to vector3

    var move_direction := Vector3 (move_input_vector.x, 0.0, move_input_vector.y)

    #check if input vector is ZERO to reduce unesscary errors
    if move_direction != Vector3.ZERO:
        var horrizontal_velocity := move_direction * max_speed
        self.velocity = horrizontal_velocity

    else:
        self.velocity = Vector3.ZERO



    if Input.is_action_just_pressed("jump") && is_on_floor():

        #to create a smooth parabola we want to decrease the amount of velocity evey physics tick.

        var jump : Vector3= jump_force * self.up_direction * delta

        self.velocity.y += jump_force

        _jumping = true


    ##Handles everything to do with falling

    if !is_on_floor():

        # regular falling
        if self.velocity.y >= 0:

            self.velocity -= gravity * self.up_direction * delta


        #decelerating from a jump
        if _jumping:

            jump_force -= down_force

            var jump : Vector3= jump_force * self.up_direction * delta

            self.velocity.y += jump_force

        #clamp speed to prevent decent from going over terminal velocity
        #we use maxf since we dont need a minium value for velocity

        self.velocity.y = maxf(self.velocity.y, -terminal_velocity)

    #reset when on floor
    if is_on_floor():

        _jumping = false
        jump_force = _intial_jump_force


    move_and_slide()