import sys

import pytest

from .helpers import write_header
from .runners import RunnerPywasm3 as Runner

def setup_interpreter(phash_code: str) -> Runner:
    runner = Runner(phash_code)

    runner.parse()
    runner.compile_ast()
    runner.compile_wat()
    runner.compile_wasm()
    runner.interpreter_setup()
    runner.interpreter_load()

    write_header(sys.stderr, 'Phasm')
    runner.dump_phasm_code(sys.stderr)
    write_header(sys.stderr, 'Assembly')
    runner.dump_wasm_wat(sys.stderr)

    return runner

@pytest.mark.integration_test
def test___init__():
    code_py = """
@exported
def testEntry() -> u8:
    return 13
"""

    runner = setup_interpreter(code_py)

    # Garbage in the memory so we can test for it
    runner.interpreter_write_memory(0, range(128))

    write_header(sys.stderr, 'Memory (pre run)')
    runner.interpreter_dump_memory(sys.stderr)

    runner.call('stdlib.alloc.__init__')

    write_header(sys.stderr, 'Memory (post run)')
    runner.interpreter_dump_memory(sys.stderr)

    assert (
        b'\xC0\xA1\x00\x00'
        b'\x00\x00\x00\x00'
        b'\x00\x00\x00\x00'
        b'\x10\x00\x00\x00'
        b'\x10\x11\x12\x13' # Untouched because unused
    ) == runner.interpreter_read_memory(0, 20)

@pytest.mark.integration_test
def test___alloc___no_init():
    code_py = """
@exported
def testEntry() -> u8:
    return 13
"""

    runner = setup_interpreter(code_py)

    write_header(sys.stderr, 'Memory (pre run)')
    runner.interpreter_dump_memory(sys.stderr)

    with pytest.raises(Exception, match='unreachable'):
        runner.call('stdlib.alloc.__alloc__', 32)

@pytest.mark.integration_test
def test___alloc___ok():
    code_py = """
@exported
def testEntry() -> u8:
    return 13
"""

    runner = setup_interpreter(code_py)

    write_header(sys.stderr, 'Memory (pre run)')
    runner.interpreter_dump_memory(sys.stderr)

    runner.call('stdlib.alloc.__init__')
    offset0 = runner.call('stdlib.alloc.__alloc__', 32)
    offset1 = runner.call('stdlib.alloc.__alloc__', 32)
    offset2 = runner.call('stdlib.alloc.__alloc__', 32)

    write_header(sys.stderr, 'Memory (post run)')
    runner.interpreter_dump_memory(sys.stderr)

    assert (
        b'\xC0\xA1\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x7C\x00\x00\x00'
        b'\x20\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
        b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
        b'\x00\x00\x00\x00\x20\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
        b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
        b'\x00\x00\x00\x00\x00\x00\x00\x00\x20\x00\x00\x00\x00\x00\x00\x00'
    ) == runner.interpreter_read_memory(0, 0x60)

    assert 0x14 == offset0
    assert 0x38 == offset1
    assert 0x5C == offset2