"""Unit tests for GPURingBuffer and KVLedger."""
import torch
import sys
import os

sys.path.insert(0, os.path.join(os.path.dirname(__file__), "..", ".."))

from arbitor.attention.ring_buffer import GPURingBuffer
from arbitor.attention.kv_ledger import KVLedger


def test_rb_append_wrap():
    rb = GPURingBuffer(4)
    for i in range(6):
        rb.append(i)
    assert rb.get_last_n(3).tolist() == [3, 4, 5], f"got {rb.get_last_n(3).tolist()}"
    print(" PASS test_rb_append_wrap")


def test_rb_contiguous_no_wrap():
    rb = GPURingBuffer(4)
    for i in range(3):
        rb.append(i)
    assert rb.get_last_n(3).tolist() == [0, 1, 2]
    print(" PASS test_rb_contiguous_no_wrap")


def test_rb_empty():
    rb = GPURingBuffer(4)
    assert rb.get_last_n(3).numel() == 0
    print(" PASS test_rb_empty")


def test_rb_reset():
    rb = GPURingBuffer(4)
    for i in range(3):
        rb.append(i)
    rb.reset()
    assert rb.ptr == 0 and rb.size == 0
    assert rb.get_last_n(3).numel() == 0
    print(" PASS test_rb_reset")


def test_rb_multi_dim():
    rb = GPURingBuffer(3, dtype=torch.float32, dim=4)
    assert rb.buffer.shape == (3, 4)
    for i in range(3):
        rb.append(torch.ones(4) * i)
    last = rb.get_last_n(2)
    assert last.shape == (2, 4), f"shape {last.shape}"
    print(" PASS test_rb_multi_dim")


def test_rb_get_all():
    rb = GPURingBuffer(4)
    for i in range(6):
        rb.append(i)
    all_vals = rb.get_all()
    assert all_vals.tolist() == [2, 3, 4, 5], f"got {all_vals.tolist()}"
    print(" PASS test_rb_get_all")


def test_rb_partial():
    rb = GPURingBuffer(8)
    for i in range(5):
        rb.append(i)
    assert rb.get_all().tolist() == [0, 1, 2, 3, 4]
    assert rb.get_last_n(3).tolist() == [2, 3, 4]
    print(" PASS test_rb_partial")


def test_kv_ledger_basic():
    kv = KVLedger(256)
    for i in range(100):
        kv.append(i)
    assert len(kv) == 100
    assert kv.get_sliding_window(5).tolist() == [95, 96, 97, 98, 99]
    print(" PASS test_kv_ledger_basic")


def test_kv_ledger_sliding_window():
    kv = KVLedger(32)
    for i in range(32):
        kv.append(i)
    last_5 = kv.get_sliding_window(5)
    assert last_5.tolist() == [27, 28, 29, 30, 31], f"got {last_5.tolist()}"
    print(" PASS test_kv_ledger_sliding_window")


def test_kv_ledger_sparse():
    kv = KVLedger(16)
    for i in range(10):
        kv.append(i)
    sparse = kv.get_sparse(stride=3)
    assert len(sparse) == 4, f"len={len(sparse)}"
    print(" PASS test_kv_ledger_sparse")


def test_kv_ledger_reset():
    kv = KVLedger(8)
    for i in range(5):
        kv.append(i)
    kv.reset()
    assert len(kv) == 0
    print(" PASS test_kv_ledger_reset")


def test_cuda_device_move():
    if not torch.cuda.is_available():
        print(" SKIP test_cuda_device_move (no cuda)")
        return
    rb = GPURingBuffer(4)
    rb = rb.to("cuda")
    assert rb.buffer.device.type == "cuda"
    rb.append(42)
    assert rb.get_last_n(1).tolist() == [42]
    print(" PASS test_cuda_device_move")


if __name__ == "__main__":
    test_rb_append_wrap()
    test_rb_contiguous_no_wrap()
    test_rb_empty()
    test_rb_reset()
    test_rb_multi_dim()
    test_rb_get_all()
    test_rb_partial()
    test_kv_ledger_basic()
    test_kv_ledger_sliding_window()
    test_kv_ledger_sparse()
    test_kv_ledger_reset()
    test_cuda_device_move()
    print("\nAll ring buffer tests PASS")