"""Tests für den Scanner-Server (HTTP-Upload für Backcover/EAN-Fotos)."""

from __future__ import annotations

import base64
import json
import socket
import urllib.error
import urllib.request
from pathlib import Path
from unittest.mock import patch

from musiksammlung.scanner_server import ScannerServer, _get_local_ip, print_qr


def _free_port() -> int:
    """Gibt einen freien TCP-Port zurück."""
    with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
        s.bind(("", 0))
        return s.getsockname()[1]


class TestScannerServerBasics:
    """Grundlegende ScannerServer-Tests ohne Netzwerk."""

    def test_url_format(self) -> None:
        server = ScannerServer(port=12345)
        url = server.url()
        assert url.startswith("http://")
        assert "12345" in url

    def test_get_photo_empty_queue_returns_none(self, tmp_path: Path) -> None:
        server = ScannerServer(port=_free_port(), upload_dir=tmp_path)
        assert server.get_photo(timeout=0) is None

    def test_custom_upload_dir(self, tmp_path: Path) -> None:
        server = ScannerServer(port=_free_port(), upload_dir=tmp_path)
        assert server._upload_dir == tmp_path


class TestScannerServerHttp:
    """Integrationstests mit echtem HTTP-Server."""

    def test_get_root_returns_html(self, tmp_path: Path) -> None:
        port = _free_port()
        server = ScannerServer(port=port, upload_dir=tmp_path)
        server.start()
        try:
            with urllib.request.urlopen(f"http://127.0.0.1:{port}/") as resp:
                assert resp.status == 200
                html = resp.read().decode("utf-8")
                assert "<html" in html.lower()
                assert "upload" in html.lower()
        finally:
            server.stop()

    def test_get_index_html_alias(self, tmp_path: Path) -> None:
        port = _free_port()
        server = ScannerServer(port=port, upload_dir=tmp_path)
        server.start()
        try:
            with urllib.request.urlopen(f"http://127.0.0.1:{port}/index.html") as resp:
                assert resp.status == 200
        finally:
            server.stop()

    def test_get_unknown_path_returns_404(self, tmp_path: Path) -> None:
        port = _free_port()
        server = ScannerServer(port=port, upload_dir=tmp_path)
        server.start()
        try:
            try:
                urllib.request.urlopen(f"http://127.0.0.1:{port}/unknown")
                assert False, "Should have raised HTTPError"
            except urllib.error.HTTPError as e:
                assert e.code == 404
        finally:
            server.stop()

    def test_post_upload_valid_image(self, tmp_path: Path) -> None:
        port = _free_port()
        server = ScannerServer(port=port, upload_dir=tmp_path)
        server.start()
        try:
            fake_img = b"fake image bytes for testing"
            b64 = base64.b64encode(fake_img).decode()
            payload = json.dumps({"image": f"data:image/jpeg;base64,{b64}"}).encode()
            req = urllib.request.Request(
                f"http://127.0.0.1:{port}/upload",
                data=payload,
                headers={"Content-Type": "application/json"},
            )
            with urllib.request.urlopen(req) as resp:
                data = json.loads(resp.read())
                assert data["status"] == "ok"

            photo = server.get_photo(timeout=2.0)
            assert photo is not None
            assert photo.suffix == ".jpg"
            assert photo.read_bytes() == fake_img
        finally:
            server.stop()

    def test_post_upload_png_extension(self, tmp_path: Path) -> None:
        port = _free_port()
        server = ScannerServer(port=port, upload_dir=tmp_path)
        server.start()
        try:
            b64 = base64.b64encode(b"png data").decode()
            payload = json.dumps({"image": f"data:image/png;base64,{b64}"}).encode()
            req = urllib.request.Request(
                f"http://127.0.0.1:{port}/upload",
                data=payload,
                headers={"Content-Type": "application/json"},
            )
            with urllib.request.urlopen(req):
                pass

            photo = server.get_photo(timeout=2.0)
            assert photo is not None
            assert photo.suffix == ".png"
        finally:
            server.stop()

    def test_post_upload_invalid_json_returns_400(self, tmp_path: Path) -> None:
        port = _free_port()
        server = ScannerServer(port=port, upload_dir=tmp_path)
        server.start()
        try:
            payload = b"not valid json at all"
            req = urllib.request.Request(
                f"http://127.0.0.1:{port}/upload",
                data=payload,
                headers={"Content-Type": "application/json"},
            )
            try:
                urllib.request.urlopen(req)
                assert False, "Should have raised HTTPError"
            except urllib.error.HTTPError as e:
                assert e.code == 400
        finally:
            server.stop()

    def test_post_upload_missing_image_key_returns_400(self, tmp_path: Path) -> None:
        port = _free_port()
        server = ScannerServer(port=port, upload_dir=tmp_path)
        server.start()
        try:
            payload = json.dumps({"wrong_key": "data"}).encode()
            req = urllib.request.Request(
                f"http://127.0.0.1:{port}/upload",
                data=payload,
                headers={"Content-Type": "application/json"},
            )
            try:
                urllib.request.urlopen(req)
                assert False, "Should have raised HTTPError"
            except urllib.error.HTTPError as e:
                assert e.code == 400
        finally:
            server.stop()

    def test_post_to_unknown_path_returns_404(self, tmp_path: Path) -> None:
        port = _free_port()
        server = ScannerServer(port=port, upload_dir=tmp_path)
        server.start()
        try:
            req = urllib.request.Request(
                f"http://127.0.0.1:{port}/other",
                data=b"data",
                headers={"Content-Type": "application/json"},
            )
            try:
                urllib.request.urlopen(req)
                assert False, "Should have raised HTTPError"
            except urllib.error.HTTPError as e:
                assert e.code == 404
        finally:
            server.stop()


class TestGetLocalIp:
    """Tests für _get_local_ip."""

    def test_returns_ip_string(self) -> None:
        ip = _get_local_ip()
        assert isinstance(ip, str)
        parts = ip.split(".")
        assert len(parts) == 4

    def test_fallback_on_network_error(self) -> None:
        with patch("socket.socket") as mock_sock:
            mock_sock.return_value.__enter__.return_value.connect.side_effect = OSError
            result = _get_local_ip()
        assert result == "127.0.0.1"


class TestPrintQr:
    """Tests für print_qr."""

    def test_with_qrcode_installed(self, capsys) -> None:
        # qrcode ist installiert (steht in pyproject.toml); kein Fehler erwartet
        print_qr("http://192.168.1.1:8765")
        # Ausgabe enthält mindestens etwas (QR oder leer — beides ok)

    def test_without_qrcode_graceful(self, monkeypatch) -> None:
        """Wenn qrcode nicht installiert ist, wird kein Fehler geworfen."""
        import builtins
        original_import = builtins.__import__

        def mock_import(name, *args, **kwargs):
            if name == "qrcode":
                raise ImportError("No module named 'qrcode'")
            return original_import(name, *args, **kwargs)

        monkeypatch.setattr(builtins, "__import__", mock_import)
        print_qr("http://example.com")  # darf keinen Fehler werfen