"""Tests for modules/system.py."""

from unittest.mock import AsyncMock

import pytest


def make_mock_mcp():
    tools: dict = {}

    class MockMCP:
        def tool(self):
            def decorator(fn):
                tools[fn.__name__] = fn
                return fn

            return decorator

    return MockMCP(), tools


def make_config():
    from mcp_synology_container.config import AppConfig, ConnectionConfig

    return AppConfig(
        schema_version=1,
        connection=ConnectionConfig(host="nas.local", port=443, https=True, verify_ssl=True),
    )


SAMPLE_IMAGES = {
    "images": [
        {
            "id": "sha256:aaaa",
            "repository": "nginx",
            "tags": ["1.24"],
            "size": 50 * 1024 * 1024,
        },
        {
            "id": "sha256:bbbb",
            "repository": "postgres",
            "tags": ["15"],
            "size": 80 * 1024 * 1024,
        },
        {
            "id": "sha256:cccc",
            "repository": "<none>",
            "tags": [],
            "size": 10 * 1024 * 1024,
        },
    ]
}

SAMPLE_CONTAINERS = {
    "containers": [
        {"name": "web", "status": "running", "image_id": "sha256:aaaa"},
        {"name": "db", "status": "running", "image_id": "sha256:bbbb"},
        {"name": "old", "status": "stopped", "image_id": "sha256:aaaa"},
    ]
}


# ──────────────────────────────────────────────────────────────────────────────
#  system_df
# ──────────────────────────────────────────────────────────────────────────────


@pytest.mark.asyncio
async def test_system_df_shows_image_stats():
    from mcp_synology_container.modules.system import register_system

    client = AsyncMock()

    async def mock_request(api, method, **kwargs):
        if api == "SYNO.Docker.Image":
            return SAMPLE_IMAGES
        if api == "SYNO.Docker.Container":
            return SAMPLE_CONTAINERS
        return {}

    client.request.side_effect = mock_request
    mcp, tools = make_mock_mcp()
    register_system(mcp, make_config(), client)

    result = await tools["system_df"]()
    assert "Images" in result
    assert "3" in result  # total images
    assert "Containers" in result


@pytest.mark.asyncio
async def test_system_df_reclaimable():
    """Unused images (not referenced by any container) are counted as reclaimable."""
    from mcp_synology_container.modules.system import register_system

    client = AsyncMock()

    async def mock_request(api, method, **kwargs):
        if api == "SYNO.Docker.Image":
            return SAMPLE_IMAGES
        if api == "SYNO.Docker.Container":
            return SAMPLE_CONTAINERS
        return {}

    client.request.side_effect = mock_request
    mcp, tools = make_mock_mcp()
    register_system(mcp, make_config(), client)

    result = await tools["system_df"]()
    # sha256:cccc (<none>) is not referenced by any container → reclaimable
    assert "reclaimable" in result
    assert "unused" in result


@pytest.mark.asyncio
async def test_system_df_running_vs_stopped():
    from mcp_synology_container.modules.system import register_system

    client = AsyncMock()

    async def mock_request(api, method, **kwargs):
        if api == "SYNO.Docker.Image":
            return SAMPLE_IMAGES
        if api == "SYNO.Docker.Container":
            return SAMPLE_CONTAINERS
        return {}

    client.request.side_effect = mock_request
    mcp, tools = make_mock_mcp()
    register_system(mcp, make_config(), client)

    result = await tools["system_df"]()
    assert "running" in result
    assert "stopped" in result


@pytest.mark.asyncio
async def test_system_df_image_api_error_graceful():
    """Container data is still shown even when image API fails."""
    from mcp_synology_container.dsm_client import SynologyError
    from mcp_synology_container.modules.system import register_system

    client = AsyncMock()

    async def mock_request(api, method, **kwargs):
        if api == "SYNO.Docker.Image":
            raise SynologyError("image API down", code=102)
        if api == "SYNO.Docker.Container":
            return SAMPLE_CONTAINERS
        return {}

    client.request.side_effect = mock_request
    mcp, tools = make_mock_mcp()
    register_system(mcp, make_config(), client)

    result = await tools["system_df"]()
    # Should still show container section and a warning
    assert "Containers" in result or "Warnings" in result


@pytest.mark.asyncio
async def test_system_df_no_images():
    from mcp_synology_container.modules.system import register_system

    client = AsyncMock()

    async def mock_request(api, method, **kwargs):
        if api == "SYNO.Docker.Image":
            return {"images": []}
        if api == "SYNO.Docker.Container":
            return {"containers": []}
        return {}

    client.request.side_effect = mock_request
    mcp, tools = make_mock_mcp()
    register_system(mcp, make_config(), client)

    result = await tools["system_df"]()
    assert "0" in result


# ──────────────────────────────────────────────────────────────────────────────
#  system_prune
# ──────────────────────────────────────────────────────────────────────────────


@pytest.mark.asyncio
async def test_system_prune_preview():
    from mcp_synology_container.modules.system import register_system

    client = AsyncMock()

    async def mock_request(api, method, **kwargs):
        if api == "SYNO.Docker.Image":
            return SAMPLE_IMAGES
        if api == "SYNO.Docker.Container":
            return SAMPLE_CONTAINERS
        return {}

    client.request.side_effect = mock_request
    mcp, tools = make_mock_mcp()
    register_system(mcp, make_config(), client)

    result = await tools["system_prune"]()
    assert "preview" in result.lower()
    assert "confirmed=True" in result
    # prune API must NOT be called
    calls = [c.args[:2] for c in client.request.call_args_list]
    assert ("SYNO.Docker.Utils", "prune") not in calls


@pytest.mark.asyncio
async def test_system_prune_preview_lists_dangling():
    """Preview names dangling/unused images and stopped containers."""
    from mcp_synology_container.modules.system import register_system

    client = AsyncMock()

    async def mock_request(api, method, **kwargs):
        if api == "SYNO.Docker.Image":
            return SAMPLE_IMAGES
        if api == "SYNO.Docker.Container":
            return SAMPLE_CONTAINERS
        return {}

    client.request.side_effect = mock_request
    mcp, tools = make_mock_mcp()
    register_system(mcp, make_config(), client)

    result = await tools["system_prune"]()
    # <none>:<none> is dangling
    assert "<none>" in result
    # "old" container is stopped
    assert "old" in result


@pytest.mark.asyncio
async def test_system_prune_confirmed():
    from mcp_synology_container.modules.system import register_system

    client = AsyncMock()

    async def mock_request(api, method, **kwargs):
        if api == "SYNO.Docker.Image":
            return SAMPLE_IMAGES
        if api == "SYNO.Docker.Container":
            return SAMPLE_CONTAINERS
        if api == "SYNO.Docker.Utils" and method == "prune":
            return {"SpaceReclaimed": 10 * 1024 * 1024}
        return {}

    client.request.side_effect = mock_request
    mcp, tools = make_mock_mcp()
    register_system(mcp, make_config(), client)

    result = await tools["system_prune"](confirmed=True)
    assert "completed" in result.lower()
    assert "MiB" in result or "reclaimed" in result.lower()


@pytest.mark.asyncio
async def test_system_prune_confirmed_no_space_reported():
    """Prune works even when DSM doesn't report reclaimed bytes."""
    from mcp_synology_container.modules.system import register_system

    client = AsyncMock()

    async def mock_request(api, method, **kwargs):
        if api == "SYNO.Docker.Image":
            return SAMPLE_IMAGES
        if api == "SYNO.Docker.Container":
            return SAMPLE_CONTAINERS
        if api == "SYNO.Docker.Utils" and method == "prune":
            return {}
        return {}

    client.request.side_effect = mock_request
    mcp, tools = make_mock_mcp()
    register_system(mcp, make_config(), client)

    result = await tools["system_prune"](confirmed=True)
    assert "completed" in result.lower()
    assert "not reported" in result


@pytest.mark.asyncio
async def test_system_prune_api_error():
    from mcp_synology_container.dsm_client import SynologyError
    from mcp_synology_container.modules.system import register_system

    client = AsyncMock()

    async def mock_request(api, method, **kwargs):
        if api == "SYNO.Docker.Image":
            return SAMPLE_IMAGES
        if api == "SYNO.Docker.Container":
            return SAMPLE_CONTAINERS
        if api == "SYNO.Docker.Utils" and method == "prune":
            raise SynologyError("prune failed", code=100)
        return {}

    client.request.side_effect = mock_request
    mcp, tools = make_mock_mcp()
    register_system(mcp, make_config(), client)

    result = await tools["system_prune"](confirmed=True)
    assert "Error" in result