t = require('luaunit')
local phys = require('phys')

function TestUpdate()
    local actor = { x = 0, y = 0, speed = 1, angle = math.pi }
    phys.update(actor, 0.1)
    t.assertAlmostEquals(
        actor,
        { x = -0.1, y = 0, speed = 1, angle = math.pi })
end

function TestApply()
    local actor = { x = 0, y = 0, speed = 1, angle = math.pi }

    phys.apply(actor, { speed = 1, angle = 0 })
    t.assertAlmostEquals(
        { x = actor.x, y = actor.y, speed = actor.speed },
        { x = 0, y = 0, speed = 0 })

    phys.apply(actor, { speed = 1, angle = math.pi })
    t.assertAlmostEquals(
        actor,
        { x = 0, y = 0, speed = 1, angle = math.pi }
    )

    phys.apply(actor, { speed = 1, angle = math.pi / 2 })
    t.assertAlmostEquals(
        actor,
        { x = 0, y = 0, speed = math.sqrt(2), angle = math.pi * 3 / 4 }
    )
end

os.exit(t.LuaUnit.run())