from __future__ import annotations

import asyncio
import sys
import urllib.parse
from pathlib import Path
from typing import Any, cast

import httpx
import pytest

sys.path.insert(0, str(Path(__file__).resolve().parents[1] / "scripts"))

from gibby.client import OpenAIAPIError
from gibby.models import UsageSnapshot, UsageWindow
from gibby.oauth import build_authorize_url, generate_pkce_pair
from gibby.settings import Settings
from oauth_helper import (  # type: ignore[import-not-found]
    exchange_and_store_account,
    parse_redirect_url,
    wait_for_callback,
)
from gibby.store import JsonStateStore


class FakeClient:
    def __init__(
        self,
        settings: Settings,
        usage: UsageSnapshot,
        *,
        transient_usage_failure: bool = False,
    ):
        self.settings = settings
        self.usage = usage
        self.transient_usage_failure = transient_usage_failure

    async def exchange_code(self, code: str, verifier: str) -> tuple[str, str, int]:
        return ("access-token", "refresh-token", 1776000000)

    async def refresh_access_token(self, refresh_token: str) -> tuple[str, str, int]:
        return ("access-token", refresh_token, 1776000000)

    async def fetch_usage_payload(self, access_token: str) -> dict:
        if self.transient_usage_failure:
            raise OpenAIAPIError("usage timeout", permanent=False)
        primary_window = self.usage.primary_window
        assert primary_window is not None
        secondary_window = (
            {
                "used_percent": self.usage.secondary_window.used_percent,
                "reset_at": self.usage.secondary_window.reset_at,
            }
            if self.usage.secondary_window is not None
            else None
        )
        return {
            "email": "oauth@example.com",
            "account_id": "oauth-1",
            "rate_limit": {
                "allowed": self.usage.allowed,
                "limit_reached": self.usage.limit_reached,
                "primary_window": {
                    "used_percent": primary_window.used_percent,
                    "reset_at": primary_window.reset_at,
                },
                "secondary_window": secondary_window,
            },
        }


def make_usage(primary: int, secondary: int | None = None) -> UsageSnapshot:
    return UsageSnapshot(
        checked_at=1775000000,
        primary_window=UsageWindow(primary, 1775000100),
        secondary_window=UsageWindow(secondary or 0, 1775000100)
        if secondary is not None
        else None,
    )


def test_generate_pkce_pair_shapes() -> None:
    verifier, challenge = generate_pkce_pair()
    assert len(verifier) > 40
    assert len(challenge) > 40
    assert "=" not in challenge


def test_build_authorize_url_contains_redirect_and_state() -> None:
    settings = Settings(callback_host="localhost", callback_port=1455)
    url = build_authorize_url(settings, "challenge", "state-123")
    parsed = urllib.parse.urlparse(url)
    query = urllib.parse.parse_qs(parsed.query)
    assert parsed.scheme == "https"
    assert query["redirect_uri"] == ["http://localhost:1455/auth/callback"]
    assert query["state"] == ["state-123"]
    assert query["code_challenge"] == ["challenge"]


def test_parse_redirect_url_extracts_code_and_state() -> None:
    code, state = parse_redirect_url(
        "http://127.0.0.1:1455/auth/callback?code=abc&state=xyz"
    )
    assert code == "abc"
    assert state == "xyz"


@pytest.mark.asyncio
async def test_wait_for_callback_receives_code_and_state() -> None:
    task = asyncio.create_task(
        wait_for_callback("127.0.0.1", 18555, "state-1", timeout=5)
    )
    await asyncio.sleep(0.05)
    async with httpx.AsyncClient() as client:
        response = await client.get(
            "http://127.0.0.1:18555/auth/callback?code=abc123&state=state-1",
            timeout=5,
        )
    result = await task

    assert response.status_code == 200
    assert result == ("abc123", "state-1")


@pytest.mark.asyncio
async def test_exchange_and_store_account_populates_usage_snapshot(
    tmp_path: Path,
) -> None:
    store = JsonStateStore(tmp_path / "accounts.json")
    settings = Settings(data_dir=tmp_path)
    client = FakeClient(settings, make_usage(12, 3))

    account = await exchange_and_store_account(
        store,
        cast(Any, client),
        "code",
        "verifier",
        False,
    )

    assert account.usage is not None
    assert account.email == "oauth@example.com"
    assert account.usage.primary_window is not None
    assert account.usage.primary_window.used_percent == 12
    assert account.usage.secondary_window is not None
    assert account.usage.secondary_window.used_percent == 3


@pytest.mark.asyncio
async def test_exchange_and_store_account_raises_on_transient_usage_failure(
    tmp_path: Path,
) -> None:
    store = JsonStateStore(tmp_path / "accounts.json")
    settings = Settings(data_dir=tmp_path)
    client = FakeClient(settings, make_usage(12, 3), transient_usage_failure=True)

    with pytest.raises(OpenAIAPIError):
        await exchange_and_store_account(
            store,
            cast(Any, client),
            "code",
            "verifier",
            False,
        )

    assert store.load().accounts == []