local body = entity.rigidbody

local props = {}

local function def_prop(name, def_value)
    props[name] = SAVED_DATA[name] or ARGS[name] or def_value
    this["get_"..name] = function() return props[name] end
    this["set_"..name] = function(value)
        props[name] = value
        if math.abs(value - def_value) < 1e-7 then
            SAVED_DATA[name] = nil
        else
            SAVED_DATA[name] = value
        end
    end
end

def_prop("jump_force", 0.0)
def_prop("air_damping", 1.0)
def_prop("ground_damping", 1.0)
def_prop("movement_speed", 3.0)
def_prop("run_speed_mul", 1.5)
def_prop("crouch_speed_mul", 0.35)
def_prop("flight_speed_mul", 4.0)
def_prop("cheat_speed_mul", 5.0)
def_prop("gravity_scale", 1.0)

function jump(multiplier)
    if body:is_grounded() then
        local vel = body:get_vel()
        body:set_vel(
            vec3.add(vel, {0, props.jump_force * (multiplier or 1.0), 0}, vel))
    end
end

function elevate(speed, delta, vel)
    vel = vel or body:get_vel()
    body:set_vel(
        vec3.add(vel, {0, speed * delta, 0}, vel))
end

function lower(speed, delta, vel)
    vel = vel or body:get_vel()
    body:set_vel(
        vec3.add(vel, {0, -speed * delta, 0}, vel))
end

function move_horizontal(speed, dir, vel)
    vel = vel or body:get_vel()
    if vec3.length(dir) > 0.0 then
        vec3.normalize(dir, dir)

        vel[1] = dir[1] * speed
        vel[3] = dir[3] * speed
    end
    body:set_vel(vel)
end

function on_physics_update(tps)
    local delta = (1.0 / tps)
    local pid = entity:get_player()
    if pid and hud and not hud.is_inventory_open() and not menu.page ~= "" then
        -- todo: replace with entity direction
        local cam = cameras.get("core:first-person")
        local front = cam:get_front()
        local right = cam:get_right()
        front[2] = 0.0
        vec3.normalize(front, front)

        local grounded = body:is_grounded()

        local isjump = input.is_active('movement.jump')
        local issprint = input.is_active('movement.sprint')
        local iscrouch = input.is_active('movement.crouch')
        local isforward = input.is_active('movement.forward')
        local ischeat = input.is_active('movement.cheat')
        local isback = input.is_active('movement.back')
        local isleft = input.is_active('movement.left')
        local isright = input.is_active('movement.right')
        local flight = player.is_flight(pid)
        local noclip = player.is_noclip(pid)

        local vel = body:get_vel()

        local speed = props.movement_speed

        if flight then
            speed = speed * props.flight_speed_mul
        elseif issprint then
            speed = speed * props.run_speed_mul
        elseif iscrouch and grounded then
            speed = speed * props.crouch_speed_mul
        end
        body:set_crouching(iscrouch)

        if ischeat then
            speed = speed * props.cheat_speed_mul
        end

        local dir = {0, 0, 0}
        if isforward then
            vec3.add(dir, front, dir)
        end
        if isback then
            vec3.sub(dir, front, dir)
        end
        if isright then
            vec3.add(dir, right, dir)
        end
        if isleft then
            vec3.sub(dir, right, dir)
        end

        if vec3.length(dir) > 0.0 then
            move_horizontal(speed, dir, vel)
        end

        if flight then
            if isjump then
                elevate(speed * 8.0, delta)
            elseif iscrouch then
                lower(speed * 8.0, delta)
            end
        elseif isjump then
            jump()
        end
        body:set_vdamping(flight)
        body:set_gravity_scale(flight and 0.0 or props.gravity_scale)
        body:set_linear_damping(
            (flight or not grounded) and props.air_damping or props.ground_damping
        )
        body:set_body_type(noclip and "kinematic" or "dynamic")
    end
end