use crate::*;

use rand::Rng;

#[test]
fn chunks_exact_mut_random() {
	const MAX_APPEND_LEN: usize = 1023;
	const CHUNK_SIZE: usize = 32;
	const BUF_SIZE: usize = 1024;

	let mut rng = rand::thread_rng();
	let mut ringbuf = RingBuf::new(BUF_SIZE, 0_u32);
	let mut current_value = 0;
	for _ in 0_u32..1024 {
		let append_len = rng.gen_range(0..MAX_APPEND_LEN);
		let overwritten = append_len;
		let available = ringbuf.available();
		assert_eq!(
			ringbuf.push_from_iter_overflowing(
				current_value as u32..current_value as u32 + append_len as u32
			),
			append_len
		);
		assert_eq!((available + append_len).min(BUF_SIZE), ringbuf.available());
		dbg!(append_len);
		dbg!(current_value);
		if append_len + available > BUF_SIZE {
			current_value += append_len - (BUF_SIZE - available);
		}
		dbg!(current_value);
		ringbuf.align_skip(CHUNK_SIZE);
		for (j, chunk) in ringbuf.chunks_exact_mut(CHUNK_SIZE).enumerate() {
			assert_eq!(chunk.len(), CHUNK_SIZE);
			for (k, v) in chunk.iter().enumerate() {
				assert_eq!(
					*v as usize,
					current_value - current_value % CHUNK_SIZE + j * CHUNK_SIZE + k
				);
			}
		}
		current_value += append_len;
	}
}

#[test]
fn chunks_exact_mut_manual() {
	let mut ringbuf = RingBuf::new(8, 0_u32);

	assert_eq!(ringbuf.push_from_iter(1..4), 3);
	assert_eq!(ringbuf.available(), 3);
	let mut iter = ringbuf.chunks_exact_mut(4);
	assert_eq!(iter.next(), None);
	assert_eq!(ringbuf.available(), 3);
	assert!(ringbuf.push(4));
	assert_eq!(ringbuf.available(), 4);
	let mut iter = ringbuf.chunks_exact_mut(4);
	assert_eq!(iter.next(), Some([1, 2, 3, 4].as_mut_slice()));
	assert_eq!(iter.next(), None);
	assert_eq!(ringbuf.available(), 0);
	assert_eq!(ringbuf.push_from_iter(5..8), 3);
	assert_eq!(ringbuf.available(), 3);
	let mut iter = ringbuf.chunks_exact_mut(4);
	assert_eq!(iter.next(), None);
	assert_eq!(ringbuf.push_from_iter_overflowing(8..14), 6);
	assert_eq!(ringbuf.available(), 8);
	dbg!("{:?}", ringbuf.raw_slice());
	assert_eq!(ringbuf.align_skip(4), 3);
	let mut iter = ringbuf.chunks_exact_mut(4);
	assert_eq!(iter.next(), Some([9, 10, 11, 12].as_mut_slice()));
	assert_eq!(iter.next(), None);
	assert_eq!(ringbuf.read_first_one(), Some(&13));
	assert_eq!(ringbuf.available(), 0);
}

#[test]
fn push_from_slice_overflowing() {
	let mut ringbuf = RingBuf::new(8, 0_u32);

	ringbuf.push_from_slice_overflowing(&[1, 2, 3, 4, 5]);
	dbg!("{:?}", ringbuf.raw_slice());
	ringbuf.push_from_slice_overflowing(&[6, 7, 8, 9, 10, 11]);
	dbg!("{:?}", ringbuf.raw_slice());
	assert_eq!(
		ringbuf.read_all_slices(),
		([4, 5, 6, 7, 8].as_slice(), [9, 10, 11].as_slice())
	);
}

#[test]
fn align_skip_basic() {
	let mut ringbuf = RingBuf::new(8, 0_u32);

	assert_eq!(ringbuf.align_skip(4), 0);
	assert_eq!(ringbuf.available(), 0);
	assert_eq!(ringbuf.read_index, 0);
	assert_eq!(ringbuf.write_index, 0);

	assert!(ringbuf.push(1));
	assert_eq!(ringbuf.align_skip(4), 0);
	assert_eq!(ringbuf.available(), 1);
	assert_eq!(ringbuf.read_index, 0);
	assert_eq!(ringbuf.write_index, 1);

	assert!(ringbuf.push(1));
	assert_eq!(ringbuf.align_skip(4), 0);
	assert_eq!(ringbuf.available(), 2);
	assert_eq!(ringbuf.read_index, 0);
	assert_eq!(ringbuf.write_index, 2);

	assert!(ringbuf.push(1));
	assert_eq!(ringbuf.align_skip(4), 0);
	assert_eq!(ringbuf.available(), 3);
	assert_eq!(ringbuf.read_index, 0);
	assert_eq!(ringbuf.write_index, 3);

	assert!(ringbuf.push(1));
	assert_eq!(ringbuf.align_skip(4), 0);
	assert_eq!(ringbuf.available(), 4);
	assert_eq!(ringbuf.read_index, 0);
	assert_eq!(ringbuf.write_index, 4);

	assert_eq!(ringbuf.read_first_one(), Some(&1));
	assert_eq!(ringbuf.align_skip(4), 3);
	assert_eq!(ringbuf.available(), 0);
	assert_eq!(ringbuf.read_index, 4);
	assert_eq!(ringbuf.write_index, 4);
}

#[test]
fn align_skip_overflow() {
	let mut ringbuf = RingBuf::new(8, 0_u32);

	ringbuf.push_from_slice_overflowing(&[1, 2, 3, 4, 5, 6]);
	assert_eq!(ringbuf.read_first_slices(5).0, &[1, 2, 3, 4, 5]);
	assert_eq!(ringbuf.align_skip(4), 1);
	assert_eq!(ringbuf.available(), 0);
	assert_eq!(ringbuf.read_index, 0);
	assert_eq!(ringbuf.write_index, 0);
}