from contextlib import asynccontextmanager
from typing import AsyncIterator
from typing import List
from unittest import mock

from sqlalchemy.dialects import postgresql
from sqlalchemy.sql import Executable

from clean_python import Json
from clean_python.sql import SQLProvider

__all__ = ["FakeSQLDatabase", "assert_query_equal"]


class FakeSQLDatabase(SQLProvider):
    def __init__(self):
        self.queries: List[List[Executable]] = []
        self.result = mock.Mock(return_value=[])

    async def execute(self, query: Executable) -> List[Json]:
        self.queries.append([query])
        return self.result()

    @asynccontextmanager
    async def transaction(self) -> AsyncIterator["SQLProvider"]:
        x = FakeSQLTransaction(result=self.result)
        self.queries.append(x.queries)
        yield x


class FakeSQLTransaction(SQLProvider):
    def __init__(self, result: mock.Mock):
        self.queries: List[Executable] = []
        self.result = result

    async def execute(self, query: Executable) -> List[Json]:
        self.queries.append(query)
        return self.result()


def assert_query_equal(q: Executable, expected: str, literal_binds: bool = True):
    """There are two ways of 'binding' parameters (for testing!):

    literal_binds=True: use the built-in sqlalchemy way, which fails on some datatypes (Range)
    literal_binds=False: do it yourself using %, there is no 'mogrify' so don't expect quotes.
    """
    assert isinstance(q, Executable)
    compiled = q.compile(
        compile_kwargs={"literal_binds": literal_binds},
        dialect=postgresql.dialect(),
    )
    if not literal_binds:
        actual = str(compiled) % compiled.params
    else:
        actual = str(compiled)
    actual = actual.replace("\n", "").replace("  ", " ")
    assert actual == expected