import io
import time

import pytest
from PIL import Image

from notify import staticmap


class _FakeResponse:
    def __init__(self, content):
        self.content = content

    def raise_for_status(self):
        pass


class _FakeAsyncClient:
    def __init__(self, content=None, exc=None, **kwargs):
        self._content = content
        self._exc = exc

    async def __aenter__(self):
        return self

    async def __aexit__(self, *args):
        return False

    async def get(self, url):
        if self._exc:
            raise self._exc
        return _FakeResponse(self._content)


def _make_tile_png() -> bytes:
    buf = io.BytesIO()
    Image.new("RGB", (256, 256), color="green").save(buf, format="PNG")
    return buf.getvalue()


def test_sign_map_token_is_deterministic_and_tamper_evident():
    exp = int(time.time()) + 300
    sig1 = staticmap.sign_map_token(28.6139, 77.2090, exp)
    sig2 = staticmap.sign_map_token(28.6139, 77.2090, exp)
    assert sig1 == sig2
    assert sig1 != staticmap.sign_map_token(28.6140, 77.2090, exp)
    assert sig1 != staticmap.sign_map_token(28.6139, 77.2091, exp)
    assert sig1 != staticmap.sign_map_token(28.6139, 77.2090, exp + 1)


def test_sign_map_token_rounds_to_fixed_precision():
    """A lat/lon that round-trips through a query string (parsed back to
    float by FastAPI) must still verify — both sides format to the same
    5-decimal precision before signing (see sign_map_token's docstring)."""
    exp = int(time.time()) + 300
    lat_str, lon_str = f"{28.6139:.5f}", f"{77.209:.5f}"
    built_sig = staticmap.sign_map_token(float(lat_str), float(lon_str), exp)
    # Simulates the endpoint re-parsing the exact query-string values.
    reparsed_sig = staticmap.sign_map_token(float(lat_str), float(lon_str), exp)
    assert built_sig == reparsed_sig


@pytest.mark.asyncio
async def test_render_static_map_returns_correctly_sized_png(monkeypatch):
    monkeypatch.setattr(staticmap.httpx, "AsyncClient", lambda **kw: _FakeAsyncClient(content=_make_tile_png()))

    result = await staticmap.render_static_map(28.6139, 77.2090)
    assert result is not None
    img = Image.open(io.BytesIO(result))
    assert img.format == "PNG"
    assert img.size == (staticmap._WIDTH, staticmap._HEIGHT)


@pytest.mark.asyncio
async def test_render_static_map_returns_none_on_fetch_failure(monkeypatch):
    monkeypatch.setattr(staticmap.httpx, "AsyncClient", lambda **kw: _FakeAsyncClient(exc=RuntimeError("boom")))
    assert await staticmap.render_static_map(28.6139, 77.2090) is None


@pytest.mark.asyncio
async def test_render_static_map_rejects_out_of_range_coordinates():
    assert await staticmap.render_static_map(999, 0) is None
    assert await staticmap.render_static_map(0, -999) is None