import pytest

from phasm.type3.entry import Type3Exception

from ..helpers import Suite
from .test_natnum import FLOAT_TYPES, INT_TYPES


@pytest.mark.integration_test
@pytest.mark.parametrize('length', [1, 5, 13])
@pytest.mark.parametrize('a_type', INT_TYPES + FLOAT_TYPES)
def test_foldable_sum(length, a_type):
    code_py = f"""
@exported
def testEntry(x: {a_type}[{length}]) -> {a_type}:
    return sum(x)
"""

    in_put = tuple(range(length))

    result = Suite(code_py).run_code(in_put)

    assert sum(in_put) == result.returned_value

@pytest.mark.integration_test
def test_foldable_sum_not_natnum():
    code_py = """
class Foo:
    bar: i32

@exported
def testEntry(x: Foo[4]) -> Foo:
    return sum(x)
"""

    with pytest.raises(Type3Exception, match='Missing type class instantation: NatNum Foo'):
        Suite(code_py).run_code()

@pytest.mark.integration_test
def test_foldable_foldl_size():
    code_py = """
def u8_or(l: u8, r: u8) -> u8:
    return l | r

@exported
def testEntry(b: bytes) -> u8:
    return foldl(u8_or, 128, b)
"""
    suite = Suite(code_py)

    result = suite.run_code(b'')
    assert 128 == result.returned_value

    result = suite.run_code(b'\x80')
    assert 128 == result.returned_value

    result = suite.run_code(b'\x80\x40')
    assert 192 == result.returned_value

    result = suite.run_code(b'\x80\x40\x20\x10')
    assert 240 == result.returned_value

    result = suite.run_code(b'\x80\x40\x20\x10\x08\x04\x02\x01')
    assert 255 == result.returned_value

@pytest.mark.integration_test
@pytest.mark.parametrize('direction, exp_result', [
    ('foldl', -55, ),
    ('foldr', -5, ),
])
def test_foldable_foldl_foldr(direction, exp_result):
    # See https://stackoverflow.com/a/13280185
    code_py = f"""
def i32_sub(l: i32, r: i32) -> i32:
    return l - r

@exported
def testEntry(b: i32[10]) -> i32:
    return {direction}(i32_sub, 0, b)
"""
    suite = Suite(code_py)

    result = suite.run_code(tuple(range(1, 10)))
    assert exp_result == result.returned_value

@pytest.mark.integration_test
@pytest.mark.parametrize('in_typ', ['i8', 'i8[3]'])
def test_foldable_argument_must_be_a_function(in_typ):
    code_py = f"""
@exported
def testEntry(x: {in_typ}, y: i32, z: i64[3]) -> i32:
    return foldl(x, y, z)
"""

    r_in_typ = in_typ.replace('[', '\\[').replace(']', '\\]')

    with pytest.raises(Type3Exception, match=f'{r_in_typ} must be a function instead'):
        Suite(code_py).run_code()

@pytest.mark.integration_test
def test_foldable_argument_must_be_right_function():
    code_py = """
def foo(l: i32, r: i64) -> i64:
    return extend(l) + r

@exported
def testEntry(i: i64, l: i64[3]) -> i64:
    return foldr(foo, i, l)
"""

    with pytest.raises(Type3Exception, match=r'\(i64 -> i64 -> i64\) must be \(i32 -> i64 -> i64\) instead'):
        Suite(code_py).run_code()

@pytest.mark.integration_test
def test_foldable_invalid_return_type():
    code_py = """
@exported
def testEntry(x: i32[5]) -> f64:
    return sum(x)
"""

    with pytest.raises(Type3Exception, match='i32 must be f64 instead'):
        Suite(code_py).run_code((4, 5, 6, 7, 8, ))

@pytest.mark.integration_test
def test_foldable_not_constructed():
    code_py = """
@exported
def testEntry(x: i32) -> i32:
    return sum(x)
"""

    with pytest.raises(Type3Exception, match='Missing type class instantation: Foldable i32.*i32 must be a constructed type instead'):
        Suite(code_py).run_code()

@pytest.mark.integration_test
def test_foldable_not_foldable():
    code_py = """
@exported
def testEntry(x: (i32, u32, )) -> i32:
    return sum(x)
"""

    with pytest.raises(Type3Exception, match='Missing type class instantation: Foldable tuple'):
        Suite(code_py).run_code()