module adt

fn test_is_empty() {
	mut list := DoublyLinkedList<int>{}
	assert list.is_empty() == true
	list.push_back(1)
	assert list.is_empty() == false
}

fn test_len() ? {
	mut list := DoublyLinkedList<int>{}
	assert list.len() == 0
	list.push_back(1)
	assert list.len() == 1
	list.pop_back() ?
	assert list.len() == 0
}

fn test_first() ? {
	mut list := DoublyLinkedList<int>{}
	list.push_back(1)
	assert list.first() ? == 1
	list.push_back(2)
	assert list.first() ? == 1
	list = DoublyLinkedList<int>{}
	list.first() or { return }
	assert false
}

fn test_last() ? {
	mut list := DoublyLinkedList<int>{}
	list.push_back(1)
	assert list.last() ? == 1
	list.push_back(2)
	assert list.last() ? == 2
	list = DoublyLinkedList<int>{}
	list.last() or { return }
	assert false
}

fn test_push() ? {
	mut list := DoublyLinkedList<int>{}
	list.push_back(1)
	assert list.last() ? == 1
	list.push_back(2)
	assert list.last() ? == 2
	list.push_back(3)
	assert list.last() ? == 3
}

fn test_pop() ? {
	mut list := DoublyLinkedList<int>{}
	list.push_back(1)
	list.push_back(2)
	list.push_back(3)
	assert list.pop_back() ? == 3
	list.push_back(4)
	assert list.pop_back() ? == 4
	assert list.pop_back() ? == 2
	list = DoublyLinkedList<int>{}
	list.pop_back() or { return }
	assert false
}

fn test_pop_front() ? {
	mut list := DoublyLinkedList<int>{}
	list.push_back(1)
	list.push_back(2)
	list.push_back(3)
	assert list.pop_front() ? == 1
	list.push_back(4)
	assert list.pop_front() ? == 2
	assert list.pop_front() ? == 3
	list = DoublyLinkedList<int>{}
	list.pop_front() or { return }
	assert false
}

fn test_insert() ? {
	mut list := DoublyLinkedList<int>{}
	list.push_back(1)
	list.push_back(2)
	list.push_back(3)
	// [1, 2, 3]
	list.insert(1, 111) ?
	// [1, 111, 2, 3]
	list.insert(3, 222) ?
	// [1, 111, 2, 222, 3]
	assert list.pop_back() ? == 3
	assert list.pop_back() ? == 222
	assert list.pop_front() ? == 1
	assert list.pop_front() ? == 111
}

fn test_push_front() ? {
	mut list := DoublyLinkedList<int>{}
	list.push_back(1)
	list.push_back(2)
	list.push_back(3)
	list.push_front(111)
	assert list.first() ? == 111
}

fn test_delete() ? {
	mut list := DoublyLinkedList<int>{}
	list.push_back(0)
	list.push_back(1)
	list.push_back(2)
	list.delete(1)
	assert list.first() ? == 0
	assert list.last() ? == 2
	assert list.len() == 2
	list.delete(1)
	assert list.first() ? == 0
	assert list.last() ? == 0
	assert list.len() == 1
	list.delete(0)
	assert list.len() == 0
}

fn test_iter() ? {
	mut list := DoublyLinkedList<int>{}
	for i := 0; i < 10; i++ {
		list.push_back(i * 10)
	}

	mut count := 0
	for i, v in list {
		count += 1
		assert int(i * 10) == v
	}
	assert count == 10

	// test it gets reset
	count = 0
	for i, v in list {
		count += 1
		assert int(i * 10) == v
	}
	assert count == 10
}

fn test_index() ? {
	mut list := DoublyLinkedList<int>{}
	for i := 0; i < 10; i++ {
		list.push_back(i * 10)
	}

	for i := 0; i < 10; i++ {
		assert list.index(i * 10) ? == i
	}
}

fn test_str() ? {
	mut list := DoublyLinkedList<int>{}
	list.push_back(1)
	list.push_back(2)
	list.push_back(3)
	assert list.str() == '[1, 2, 3]'
}