from decimal import Decimal

import pytest
from fastapi import FastAPI, status
from pydantic import BaseModel, ConfigDict


def get_app(
    separate_input_output_schemas: bool,
    json_schema_serialization_defaults_required: bool,
):
    class Model(BaseModel):
        model_config = ConfigDict(
            json_schema_serialization_defaults_required=json_schema_serialization_defaults_required,
        )

        foo: int = 42
        bar: Decimal  # Decimal has different schemas for input (validation) and output (serialization)

    app = FastAPI(separate_input_output_schemas=separate_input_output_schemas)

    @app.post(
        "/",
        responses={
            status.HTTP_402_PAYMENT_REQUIRED: {
                "model": Model,
            },
        },
    )
    def root(model: Model) -> Model:
        return model

    return app


@pytest.mark.parametrize("json_schema_serialization_defaults_required", [True, False])
def test_suppress_separate_io_models(
    json_schema_serialization_defaults_required: bool,
):
    """
    Case #1 - this works fine, skip this function if you want.

    Setting separate_input_output_schemas to False
    suppresses generating separate schemas for input and output
    regardless of json_schema_serialization_defaults_required value.
    """
    app = get_app(
        separate_input_output_schemas=False,
        json_schema_serialization_defaults_required=json_schema_serialization_defaults_required,
    )
    schema = app.openapi()

    assert "Model" in schema["components"]["schemas"]
    assert "Model-Input" not in schema["components"]["schemas"]
    assert "Model-Output" not in schema["components"]["schemas"]


@pytest.mark.parametrize("json_schema_serialization_defaults_required", [True, False])
def test_separate_io_models(
    json_schema_serialization_defaults_required: bool,
):
    """
    Case #2

    Setting separate_input_output_schemas to True
    generates separate schemas for input and output
    regardless of json_schema_serialization_defaults_required value (because we have the Decimal field),
    but (bug?) generates the "Input" schema for the custom response.
    """

    app = get_app(
        separate_input_output_schemas=True,
        json_schema_serialization_defaults_required=json_schema_serialization_defaults_required,
    )

    schema = app.openapi()

    assert "Model" not in schema["components"]["schemas"]
    assert "Model-Input" in schema["components"]["schemas"]
    assert "Model-Output" in schema["components"]["schemas"]

    # Separate Input model for the request
    assert (
        "Model-Input"
        in schema["paths"]["/"]["post"]["requestBody"]["content"]["application/json"]["schema"]["$ref"]
    )

    # Separate Output model for the 200 response
    assert (
        "Model-Output"
        in schema["paths"]["/"]["post"]["responses"]["200"]["content"]["application/json"]["schema"]["$ref"]
    )

    # Separate Output model for the 402 response
    # This fails!
    assert (
        "Model-Output"
        in schema["paths"]["/"]["post"]["responses"]["402"]["content"]["application/json"]["schema"]["$ref"]
    )