from __future__ import annotations
import unittest

from tinygrad import Tensor
from tinygrad.codegen.kernel import Kernel
from tinygrad.helpers import DEBUG
from tinygrad.ops import UOp, Ops, print_uops
from tinygrad.spec import type_verify, shape_spec
from tinygrad.shape.shapetracker import ShapeTracker
from tinygrad import dtypes
from tinygrad.shape.view import View

class InvalidASTException(Exception): pass
def helper_test_verify_ast(*stores:UOp) -> Kernel:
  sink = UOp(Ops.SINK, dtypes.void, stores)
  if DEBUG >= 3:
    for op in stores: print(op)
  try: type_verify(list(sink.toposort), shape_spec)
  except RuntimeError as e: raise InvalidASTException(e.args)
  k = Kernel(sink)
  k.linearize()
  if DEBUG >= 6: print_uops(k.uops)
  if DEBUG >= 4: print(k.to_program().src)
  return k

class TestVerifyAST(unittest.TestCase):
  def test_tiny_add(self):
    dtype = dtypes.int
    buf_0 = UOp(Ops.DEFINE_GLOBAL, dtype.ptr(), (), 0)
    buf_1 = UOp(Ops.DEFINE_GLOBAL, dtype.ptr(), (), 1)
    buf_2 = UOp(Ops.DEFINE_GLOBAL, dtype.ptr(), (), 2)
    a = UOp(Ops.LOAD, dtype, (buf_1, ShapeTracker.from_shape((32, 1)).to_uop()))
    b = UOp(Ops.LOAD, dtype, (buf_2, ShapeTracker.from_shape((32, 1)).to_uop()))
    store = UOp(Ops.STORE, dtypes.void, (buf_0, ShapeTracker.from_shape((32, 1)).to_uop(), a+b))
    helper_test_verify_ast(store)

  def test_exactly_one_full_shape(self):
    dtype = dtypes.int
    bufs = [UOp(Ops.DEFINE_GLOBAL, dtype.ptr(), (), i) for i in range(6)]
    a = UOp(Ops.LOAD, dtype, (bufs[2], ShapeTracker.from_shape((32, 1)).to_uop()))
    b = UOp(Ops.LOAD, dtype, (bufs[3], ShapeTracker.from_shape((32, 1)).to_uop()))
    st0 = UOp.store(bufs[0], ShapeTracker.from_shape((32, 1)).to_uop(), a+b)
    a = UOp(Ops.LOAD, dtype, (bufs[4], ShapeTracker.from_shape((32, 32)).to_uop()))
    b = UOp(Ops.LOAD, dtype, (bufs[5], ShapeTracker.from_shape((32, 32)).to_uop()))
    st1 = UOp.store(bufs[1], ShapeTracker.from_shape((32, 32)).to_uop(), a+b)
    with self.assertRaises(InvalidASTException): helper_test_verify_ast(st0, st1)

  def test_no_implicit_broadcasting(self):
    bufs = [UOp(Ops.DEFINE_GLOBAL, dtypes.float.ptr(), (), i) for i in range(2)]
    a = UOp(Ops.LOAD, dtypes.float, (bufs[1], ShapeTracker.from_shape((4, 32)).to_uop()))
    b = a + UOp(Ops.REDUCE_AXIS, dtypes.float, (a,), (Ops.MAX, (1,)))
    st = UOp(Ops.STORE, dtypes.void, (bufs[0], ShapeTracker.from_shape((4, 32)).to_uop(), b))
    with self.assertRaises(InvalidASTException): helper_test_verify_ast(st)

  def test_shrink_ok(self):
    bufs = [UOp(Ops.DEFINE_GLOBAL, dtypes.float.ptr(), (), i) for i in range(2)]
    a = UOp(Ops.LOAD, dtypes.float, (bufs[1], ShapeTracker((View((32, 32), strides=(32, 1), offset=0, mask=None, contiguous=True),)).to_uop()))
    b = UOp(Ops.LOAD, dtypes.float, (bufs[1], ShapeTracker((View((32, 32), strides=(0, 1), offset=0, mask=None, contiguous=False),)).to_uop()))
    st = UOp.store(bufs[0], ShapeTracker.from_shape((32, 32)).to_uop(), a+b)
    helper_test_verify_ast(st)

  def test_reduce_store(self):
    bufs = [UOp(Ops.DEFINE_GLOBAL, dtypes.float.ptr(), (), i) for i in range(2)]
    a = UOp(Ops.LOAD, dtypes.float, (bufs[1], ShapeTracker.from_shape((32, 1)).to_uop()))
    r = UOp(Ops.REDUCE_AXIS, dtypes.float, (a,), (Ops.ADD, (0,)))
    st = UOp.store(bufs[0], ShapeTracker.from_shape((32, 1)).to_uop(), r)
    with self.assertRaises(InvalidASTException): helper_test_verify_ast(st)

  def test_reduce_add_store(self):
    bufs = [UOp(Ops.DEFINE_GLOBAL, dtypes.float.ptr(), (), i) for i in range(2)]
    a = UOp(Ops.LOAD, dtypes.float, (bufs[1], ShapeTracker.from_shape((32, 1)).to_uop()))
    r = UOp(Ops.REDUCE_AXIS, dtypes.float, (a,), (Ops.ADD, (0,)))
    st = UOp.store(bufs[0], ShapeTracker.from_shape((32, 1)).to_uop(), r+a)
    with self.assertRaises(InvalidASTException): helper_test_verify_ast(st)

  def test_buffer_uops_st(self):
    a = Tensor.randn(4, 4)+2
    helper_test_verify_ast(ast:=a.schedule()[-1].ast)
    store_st = [u.st for u in ast.toposort if u.op is Ops.STORE][0]
    self.assertEqual(store_st, ShapeTracker.from_shape((4, 4)))
    const_st = [u.st for u in ast.toposort if u.op is Ops.CONST][0]
    self.assertEqual(const_st, ShapeTracker.from_shape((1, 1)).expand((4, 4)))

  @unittest.skip("questionable if we want this")
  def test_assert_swizzle(self):
    buf = UOp(Ops.DEFINE_GLOBAL, dtypes.float.ptr(), (), 0)
    a = UOp(Ops.LOAD, dtypes.float, (buf, ShapeTracker.from_shape((32, 1)).to_uop()))
    r = UOp(Ops.REDUCE_AXIS, dtypes.float, (a,), (Ops.ADD, (0,)))
    st = UOp.store(buf, ShapeTracker.from_shape((32, 1)).to_uop(), r.view(r.st.expand((32, 1)))+a)
    with self.assertRaisesRegex(InvalidASTException, "swizzle"): helper_test_verify_ast(st)

  def test_const_view_always_valid(self):
    buf = UOp(Ops.DEFINE_GLOBAL, dtypes.float.ptr(), (), 0)
    a = UOp.const(dtypes.int, 0).replace(src=(UOp(Ops.VIEW, dtypes.void, (UOp(Ops.DEVICE, arg="CPU"),), ShapeTracker.from_shape(())),))
    st = UOp.store(buf, ShapeTracker.from_shape(()).to_uop(), a.cast(dtypes.float))
    helper_test_verify_ast(st)

if __name__ == '__main__':
  unittest.main()