"""The registry is the extension point, so its contract is worth pinning down."""

from datetime import date
from typing import Optional, Sequence

import pytest

from finbot.features.base import (
    Attachment,
    BotContext,
    CommandSpec,
    Feature,
    Reply,
    Services,
    SimpleFeature,
)
from finbot.registry import DuplicateCommand, FeatureRegistry

TODAY = date(2026, 8, 15)


class Greeter(SimpleFeature):
    name = "greeter"
    description = "Greetings"
    priority = 10

    def commands(self) -> Sequence[CommandSpec]:
        return (
            CommandSpec("hello", "Say hello", aliases=("hi",)),
            CommandSpec("secret", "Hidden thing", hidden=True),
        )

    def cmd_hello(self, ctx: BotContext) -> Reply:
        return Reply(f"hello {ctx.args or 'world'}")

    def cmd_secret(self, ctx: BotContext) -> Reply:
        return Reply("shh")


class Echo(Feature):
    name = "echo"
    description = "Echo"
    priority = 50

    def handle_message(self, ctx: BotContext) -> Optional[Reply]:
        if ctx.text.startswith("say "):
            return Reply(ctx.text[4:])
        return None


class Filer(Feature):
    name = "filer"
    description = "Files"
    priority = 5

    def handle_attachment(self, ctx: BotContext) -> Optional[Reply]:
        return Reply(f"got {ctx.attachment.filename}")


class Exploder(Feature):
    name = "exploder"
    priority = 1

    def commands(self) -> Sequence[CommandSpec]:
        return (CommandSpec("boom", "Raises"),)

    def handle_command(self, ctx: BotContext) -> Reply:
        raise RuntimeError("intentional")


def make_ctx(registry, text="", command="", args="", attachment=None) -> BotContext:
    services = Services(
        settings=None, store=None, llm=None, ingestor=None, advisor=None, registry=registry
    )
    return BotContext(
        user_id=1,
        chat_id=1,
        services=services,
        today=TODAY,
        text=text,
        command=command,
        args=args,
        attachment=attachment,
    )


@pytest.fixture
def registry():
    reg = FeatureRegistry()
    reg.register_all([Greeter(), Echo(), Filer()])
    return reg


class TestRegistration:
    def test_features_sorted_by_priority(self, registry):
        assert [f.name for f in registry.features] == ["filer", "greeter", "echo"]

    def test_duplicate_command_is_rejected(self, registry):
        class Clash(SimpleFeature):
            name = "clash"

            def commands(self):
                return (CommandSpec("hello", "clashing"),)

        with pytest.raises(DuplicateCommand, match="greeter"):
            registry.register(Clash())

    def test_duplicate_alias_is_rejected(self, registry):
        class Clash(SimpleFeature):
            name = "clash"

            def commands(self):
                return (CommandSpec("other", "x", aliases=("hi",)),)

        with pytest.raises(DuplicateCommand):
            registry.register(Clash())

    def test_known_command(self, registry):
        assert registry.known_command("hello")
        assert registry.known_command("hi")
        assert not registry.known_command("nope")


class TestDispatch:
    def test_command(self, registry):
        reply = registry.dispatch(make_ctx(registry, command="hello", args="there"))
        assert reply.text == "hello there"

    def test_alias(self, registry):
        reply = registry.dispatch(make_ctx(registry, command="hi"))
        assert reply.text == "hello world"

    def test_unknown_command_is_reported(self, registry):
        reply = registry.dispatch(make_ctx(registry, command="nonsense"))
        assert "don't know" in reply.text

    def test_plain_message_routes_to_a_message_handler(self, registry):
        reply = registry.dispatch(make_ctx(registry, text="say cheese"))
        assert reply.text == "cheese"

    def test_declined_message_returns_none(self, registry):
        assert registry.dispatch(make_ctx(registry, text="unhandled")) is None

    def test_attachment_routes_to_attachment_handler(self, registry):
        attachment = Attachment(data=b"x", filename="a.csv")
        reply = registry.dispatch(make_ctx(registry, attachment=attachment))
        assert reply.text == "got a.csv"

    def test_a_failing_feature_does_not_crash_the_bot(self, registry):
        registry.register(Exploder())
        reply = registry.dispatch(make_ctx(registry, command="boom"))
        assert "went wrong" in reply.text


class TestHelpGeneration:
    def test_help_lists_visible_commands(self, registry):
        text = registry.help_text()
        assert "/hello" in text
        assert "Greetings" in text

    def test_help_omits_hidden_commands(self, registry):
        assert "/secret" not in registry.help_text()

    def test_telegram_commands_payload(self, registry):
        payload = registry.telegram_commands()
        names = {c["command"] for c in payload}
        assert "hello" in names
        assert "secret" not in names
        assert all(len(c["description"]) <= 256 for c in payload)

    def test_help_escapes_html(self):
        class Sneaky(SimpleFeature):
            name = "sneaky"
            description = "<b>bold</b>"

            def commands(self):
                return (CommandSpec("x", "a & b"),)

        reg = FeatureRegistry()
        reg.register(Sneaky())
        text = reg.help_text()
        assert "&lt;b&gt;bold&lt;/b&gt;" in text
        assert "a &amp; b" in text