from fastapi import FastAPI, Request
from fastapi.openapi.docs import get_swagger_ui_html, get_swagger_ui_oauth2_redirect_html
from fastapi.responses import HTMLResponse


def init_openapi(app: FastAPI):
    # https://github.com/tiangolo/fastapi/discussions/10524
    # Copied from FastAPI, and customized the version
    async def swagger_ui_html(req: Request) -> HTMLResponse:
        root_path = req.scope.get("root_path", "").rstrip("/")
        openapi_url = root_path + app.openapi_url
        oauth2_redirect_url = app.swagger_ui_oauth2_redirect_url
        if oauth2_redirect_url:
            oauth2_redirect_url = root_path + oauth2_redirect_url
        return get_swagger_ui_html(
            openapi_url=openapi_url,
            title=app.title + " - Swagger UI",
            oauth2_redirect_url=oauth2_redirect_url,
            init_oauth=app.swagger_ui_init_oauth,
            swagger_ui_parameters=app.swagger_ui_parameters,
            swagger_js_url="https://cdn.jsdelivr.net/npm/swagger-ui-dist@5.9.0/swagger-ui-bundle.js",
            swagger_css_url="https://cdn.jsdelivr.net/npm/swagger-ui-dist@5.9.0/swagger-ui.css",
        )

    app.add_route('/docs', swagger_ui_html, include_in_schema=False)

    if app.swagger_ui_oauth2_redirect_url:

        async def swagger_ui_redirect(req: Request) -> HTMLResponse:
            return get_swagger_ui_oauth2_redirect_html()

        app.add_route(
            app.swagger_ui_oauth2_redirect_url,
            swagger_ui_redirect,
            include_in_schema=False,
        )


app = FastAPI(
    docs_url=None,  # https://github.com/tiangolo/fastapi/discussions/10524
)
init_openapi(app)