import pytest

from markitect_tool.extension import (
    ExtensionDescriptor,
    ExtensionRegistry,
    ExtensionRegistryError,
    OptionalDependency,
    ProcessingCapability,
)


def test_extension_descriptor_serializes_contract_metadata():
    descriptor = ExtensionDescriptor(
        id="query.selector",
        kind="query-engine",
        summary="Small selector query engine.",
        capabilities=[ProcessingCapability(id="ast", kind="read")],
        input_contract="Document + selector",
        output_contract="QueryMatch[]",
        diagnostics_namespace="query",
        provenance_prefix="query.selector",
        cli={"command": "mkt query"},
        docs=["docs/query-extraction.md"],
    )

    data = descriptor.to_dict()

    assert data["id"] == "query.selector"
    assert data["kind"] == "query-engine"
    assert data["capabilities"][0]["id"] == "ast"
    assert data["cli"]["command"] == "mkt query"


def test_extension_registry_lists_by_kind_and_capability():
    selector = ExtensionDescriptor(
        id="query.selector",
        kind="query-engine",
        capabilities=[ProcessingCapability(id="ast")],
    )
    local = ExtensionDescriptor(
        id="backend.local-sqlite",
        kind="backend",
        capabilities=[ProcessingCapability(id="snapshots"), ProcessingCapability(id="fts")],
    )
    registry = ExtensionRegistry([local, selector])

    assert [descriptor.id for descriptor in registry.list()] == [
        "backend.local-sqlite",
        "query.selector",
    ]
    assert [descriptor.id for descriptor in registry.list(kind="query-engine")] == [
        "query.selector"
    ]
    assert [descriptor.id for descriptor in registry.require_capability("fts")] == [
        "backend.local-sqlite"
    ]
    assert registry.require_capability("missing") == []
    assert registry.list(kind="missing") == []


def test_extension_registry_rejects_duplicate_ids():
    descriptor = ExtensionDescriptor(id="query.selector", kind="query-engine")
    registry = ExtensionRegistry([descriptor])

    with pytest.raises(ExtensionRegistryError, match="Duplicate extension id"):
        registry.register(descriptor)


def test_extension_registry_checks_optional_dependencies():
    registry = ExtensionRegistry(
        [
            ExtensionDescriptor(
                id="query.jsonpath",
                kind="query-engine",
                optional_dependencies=[
                    OptionalDependency(
                        name="jsonpath_ng",
                        package="jsonpath-ng",
                        extra="query",
                        required=True,
                    ),
                    OptionalDependency(name="tabulate"),
                ],
            )
        ]
    )

    missing = registry.check_dependencies("query.jsonpath", available_modules=set())
    available = registry.check_dependencies(
        "query.jsonpath",
        available_modules={"jsonpath_ng", "tabulate"},
    )

    assert not missing.compatible
    assert missing.missing == ["jsonpath_ng"]
    assert missing.optional_missing == ["tabulate"]
    assert available.compatible


def test_extension_descriptor_instantiates_factory():
    descriptor = ExtensionDescriptor(
        id="fake.extension",
        kind="test",
        factory=lambda: {"ready": True},
    )

    assert descriptor.instantiate() == {"ready": True}


def test_extension_descriptor_requires_factory_to_instantiate():
    descriptor = ExtensionDescriptor(id="fake.extension", kind="test")

    with pytest.raises(ExtensionRegistryError, match="has no factory"):
        descriptor.instantiate()