import os
import sys
import traceback
import logging
import pytest

from infernal_interpreter.Junk import JunkComparisonException
from infernal_interpreter.Emulator import Emulator, CodeParseException

logger = logging.getLogger(__name__)

################################################################################

code_tests = []

def add_test(name, result, register, code):
    code_tests.append((name, result, register, code))


################################################################################
# Arithmetic Operations

add_test(
    'constant $255',
    255,
    '%rsi',
    """
movq $255, %rsi
""",
)

add_test(
    'static addition 10+$20',
    30,
    '%rsi',
    """
movq $10, %rsi
addq $20, %rsi
""",
)

add_test(
    'register addition 10+20',
    30,
    '%rsi',
    """
movq $10, %rsi
movq $20, %rax
addq %rax, %rsi
""",
)

add_test(
    'register subtraction 10-20',
    -10,
    '%rsi',
    """
movq $10, %rsi
movq $20, %rax
subq %rax, %rsi
""",
)

################################################################################
# Branching

branch_tests = [
    ('jg', 10, '>', 5, 0),
    ('jg', 5, '>', 5, 1),
    ('jg', 5, '>', 10, 1),
    ('jl', 10, '<', 5, 1),
    ('jl', 5, '<', 5, 1),
    ('jl', 5, '<', 10, 0),
    ('je', 10, '==', 5, 1),
    ('je', 5, '==', 5, 0),
    ('je', 5, '==', 10, 1),
    ('jge', 10, '>=', 5, 0),
    ('jge', 5, '>=', 5, 0),
    ('jge', 5, '>=', 10, 1),
    ('jle', 10, '<=', 5, 1),
    ('jle', 5, '<=', 5, 0),
    ('jle', 5, '<=', 10, 0),
    ('jne', 10, '!=', 5, 0),
    ('jne', 5, '!=', 5, 1),
    ('jne', 5, '!=', 10, 0),
]

for jump_instruct, a, comp, b, result in branch_tests:
    add_test(
        f'branch {a} {comp} {b}={not result}',
        result,
        '%rsi',
        f"""
    start:	cmpq ${b}, ${a}
            {jump_instruct} true
            movq $1, %rsi
            jmp return
    true:	movq $0, %rsi
    return:	ret
    """,
    )

################################################################################
# Junk Comparisons

add_test(
    'invalid comparison 1',
    JunkComparisonException,
    'None',
    """
start:	movq $100, %rsp   # Set stack pointer to a random position.
        popq %rsi		  # Move a Junk value into %rsi
        cmpq $10, %rsi    # Do a Junk comparison, which triggers the `i` comp
                          # virtual register.
        jg start		  # Attempt to do a jump to the start, if (Junk-10)>0,
                          # which makes no sense, and thus throws an error.
""",
)

add_test(
    'invalid addition 1',
    JunkComparisonException,
    'None',
    """
start:	movq $100, %rsp   # Set stack pointer to a random position.
        popq %rsi		  # Move a Junk value into %rsi
        addq %rsi, %rsp   # Adds Junk to 101, which produces Junk.
        cmpq $10, %rsp    # Do a Junk comparison, which triggers the `i` comp
                          # virtual register.
        jg start		  # Attempt to do a jump to the start, if (Junk-10)>0,
                          # which makes no sense, and thus throws an error.
""",
)

add_test(
    'invalid addition 2',
    JunkComparisonException,
    'None',
    """
start:	movq $100, %rsp   # Set stack pointer to a random position.
        popq %rsi		  # Move a Junk value into %rsi
        addq %rsp, %rsi   # Adds 101 to Junk, which produces Junk.
        cmpq $10, %rsi    # Do a Junk comparison, which triggers the `i` comp
                          # virtual register.
        jg start		  # Attempt to do a jump to the start, if (Junk-10)>0,
                          # which makes no sense, and thus throws an error.
""",
)

add_test(
    'invalid subtraction 1',
    JunkComparisonException,
    'None',
    """
start:	movq $100, %rsp   # Set stack pointer to a random position.
        popq %rsi		  # Move a Junk value into %rsi
        subq %rsi, %rsp   # Adds Junk to 101, which produces Junk.
        cmpq $10, %rsp    # Do a Junk comparison, which triggers the `i` comp
                          # virtual register.
        jg start		  # Attempt to do a jump to the start, if (Junk-10)>0,
                          # which makes no sense, and thus throws an error.
""",
)

add_test(
    'invalid subtraction 2',
    JunkComparisonException,
    'None',
    """
start:	movq $100, %rsp   # Set stack pointer to a random position.
        popq %rsi		  # Move a Junk value into %rsi
        subq %rsp, %rsi   # Adds 101 to Junk, which produces Junk.
        cmpq $10, %rsi    # Do a Junk comparison, which triggers the `i` comp
                          # virtual register.
        jg start		  # Attempt to do a jump to the start, if (Junk-10)>0,
                          # which makes no sense, and thus throws an error.
""",
)

################################################################################

@pytest.mark.parametrize("name,result,register,code", code_tests)
def test_execution(name, result, register, code):
    line_nr = None
    try:
        emu = Emulator(code)
        emu.setStack('junk...', 'calling eip')
        emu.setRegs(rip=0, rbp='old bp')
    except CodeParseException as e:
        logger.exception(
            'Encountered error when parsing %s, at line %s: %s',
            name,
            e.line_nr,
            e.str,
        )
        raise
    emu = emu

    try:
        for line_nr in emu:
            pass
        if isinstance(result, BaseException):
            logger.error('Error should have happened in %s, but did not', name)
        output = emu.getVal(register)
        if output != result:
            logger.error(
                'Failed in %s. %s was %s, should be %s',
                name,
                register,
                output,
                result,
            )
    except BaseException as e:
        logger.exception('Failed')
        if not isinstance(result, BaseException) or not isinstance(e, result):
            logger.exception(
                'Encountered error in %s, at operation %s',
                name,
                emu.getVal('%rip'),
            )
            traceback.print_exc()
        raise