Add config-flow to Snapcast (#80288)

* initial stab at snapcast config flow

* fix linting errors

* Fix linter errors

* Add import flow, support unloading

* Add test for import flow

* Add dataclass and remove unique ID in config-flow

* remove translations

* Apply suggestions from code review

Co-authored-by: epenet <6771947+epenet@users.noreply.github.com>

* Refactor config flow and terminate connection

* Rename test_config_flow.py

* Fix tests

* Minor fixes

* Make mock_create_server a fixture

* Combine tests

* Abort if entry already exists

* Apply suggestions from code review

Co-authored-by: epenet <6771947+epenet@users.noreply.github.com>

* Move HomeAssistantSnapcast to own file. Clean-up last commit

* Split import flow from user flow. Fix tests.

* Use explicit asserts. Add default values to dataclass

* Change entry title to Snapcast

---------

Co-authored-by: Barrett Lowe <barrett.lowe@gmail.com>
Co-authored-by: epenet <6771947+epenet@users.noreply.github.com>

tests/components/snapcast/test_config_flow.py

@@ -0,0 +1,110 @@
+"""Test the Snapcast module."""
+
+import socket
+from unittest.mock import AsyncMock, patch
+
+import pytest
+
+from homeassistant import config_entries, setup
+from homeassistant.components.snapcast.const import DOMAIN
+from homeassistant.const import CONF_HOST, CONF_PORT
+from homeassistant.core import HomeAssistant
+from homeassistant.data_entry_flow import FlowResultType
+
+from tests.common import MockConfigEntry
+
+TEST_CONNECTION = {CONF_HOST: "snapserver.test", CONF_PORT: 1705}
+
+pytestmark = pytest.mark.usefixtures("mock_setup_entry", "mock_create_server")
+
+
+async def test_form(
+    hass: HomeAssistant, mock_setup_entry: AsyncMock, mock_create_server: AsyncMock
+) -> None:
+    """Test we get the form and handle errors and successful connection."""
+    await setup.async_setup_component(hass, "persistent_notification", {})
+    result = await hass.config_entries.flow.async_init(
+        DOMAIN, context={"source": config_entries.SOURCE_USER}
+    )
+    assert result["type"] == FlowResultType.FORM
+    assert result["step_id"] == "user"
+    assert not result["errors"]
+
+    # test invalid host error
+    with patch("snapcast.control.create_server", side_effect=socket.gaierror):
+        result = await hass.config_entries.flow.async_configure(
+            result["flow_id"],
+            TEST_CONNECTION,
+        )
+        await hass.async_block_till_done()
+
+    assert result["type"] == FlowResultType.FORM
+    assert result["step_id"] == "user"
+    assert result["errors"] == {"base": "invalid_host"}
+
+    # test connection error
+    with patch("snapcast.control.create_server", side_effect=ConnectionRefusedError):
+        result = await hass.config_entries.flow.async_configure(
+            result["flow_id"],
+            TEST_CONNECTION,
+        )
+        await hass.async_block_till_done()
+
+    assert result["type"] == FlowResultType.FORM
+    assert result["step_id"] == "user"
+    assert result["errors"] == {"base": "cannot_connect"}
+
+    # test success
+    result = await hass.config_entries.flow.async_configure(
+        result["flow_id"], TEST_CONNECTION
+    )
+    await hass.async_block_till_done()
+
+    assert result["type"] == FlowResultType.CREATE_ENTRY
+    assert result["title"] == "Snapcast"
+    assert result["data"] == {CONF_HOST: "snapserver.test", CONF_PORT: 1705}
+    assert len(mock_create_server.mock_calls) == 1
+    assert len(mock_setup_entry.mock_calls) == 1
+
+
+async def test_abort(
+    hass: HomeAssistant, mock_setup_entry: AsyncMock, mock_create_server: AsyncMock
+) -> None:
+    """Test config flow abort if device is already configured."""
+    entry = MockConfigEntry(
+        domain=DOMAIN,
+        data=TEST_CONNECTION,
+    )
+    entry.add_to_hass(hass)
+
+    result = await hass.config_entries.flow.async_init(
+        DOMAIN, context={"source": config_entries.SOURCE_USER}
+    )
+    assert result["type"] == FlowResultType.FORM
+    assert result["step_id"] == "user"
+    assert not result["errors"]
+
+    with patch("snapcast.control.create_server", side_effect=socket.gaierror):
+        result = await hass.config_entries.flow.async_configure(
+            result["flow_id"],
+            TEST_CONNECTION,
+        )
+        await hass.async_block_till_done()
+
+    assert result["type"] == FlowResultType.ABORT
+    assert result["reason"] == "already_configured"
+
+
+async def test_import(hass: HomeAssistant) -> None:
+    """Test successful import."""
+
+    result = await hass.config_entries.flow.async_init(
+        DOMAIN,
+        context={"source": config_entries.SOURCE_IMPORT},
+        data=TEST_CONNECTION,
+    )
+    await hass.async_block_till_done()
+
+    assert result["type"] == FlowResultType.CREATE_ENTRY
+    assert result["title"] == "Snapcast"
+    assert result["data"] == {CONF_HOST: "snapserver.test", CONF_PORT: 1705}