"""MCP endpoint (app/mcp_server.py): the tool surface, and that tools return the
same catalogue data as the REST API. Database tests are skipped when the local
Postgres container is not running."""
from __future__ import annotations

from decimal import Decimal

import anyio
from fastmcp import Client

from app.mcp_server import mcp


def _call(name: str, args: dict):
    async def go():
        async with Client(mcp) as c:
            return (await c.call_tool(name, args)).data
    return anyio.run(go)


def test_only_read_only_catalogue_tools_are_exposed():
    async def go():
        async with Client(mcp) as c:
            return {t.name: set(t.input_schema.get("properties", {})) for t in await c.list_tools()}
    tools = anyio.run(go)
    assert set(tools) == {"list_categories", "search_products", "get_product", "price_history"}
    assert tools["search_products"] == {"query", "category", "brand", "max_price", "min_price", "limit"}
    # Nothing that can start a run, log in, or change data.
    assert not any(w in name for name in tools for w in ("admin", "run", "login", "probe", "review"))


def test_mcp_endpoint_answers_an_initialize_handshake():
    from fastapi.testclient import TestClient

    from app.main import app

    body = {"jsonrpc": "2.0", "id": 1, "method": "initialize",
            "params": {"protocolVersion": "2025-06-18", "capabilities": {},
                       "clientInfo": {"name": "test", "version": "1"}}}
    headers = {"Accept": "application/json, text/event-stream"}
    with TestClient(app) as c:  # `with` runs the lifespan that starts MCP sessions
        r = c.post("/mcp/", json=body, headers=headers)
    assert r.status_code == 200, r.text
    assert "Electronics Catalog" in r.text  # server name in the initialize result


def test_tools_return_the_catalogue(db):
    from app.electronics.collector import Collector, RunOptions, RunStats
    from app.electronics.db import repository as repo
    from app.electronics.models import Listing
    from app.electronics.normalise.title_parser import parse_title, variant_key

    def listing(site, sku, price):
        title = "Samsung Galaxy S24 5G (8GB RAM, 256GB)"
        p = parse_title(title, "mobiles")
        l = Listing(site_domain=site, source_sku=sku, source_url=f"https://www.{site}/p/{sku}",
                    source_type="search_snippet", brand_slug="samsung", category="mobiles", title=title,
                    evidence_text=f"{title} ₹{price}", confidence=0.5, parser="test",
                    model=p.model, ram_gb=p.ram_gb, storage_gb=p.storage_gb, price=Decimal(price))
        l.model_norm, l.variant_key = p.model_norm, variant_key(p, "mobiles")
        return l

    c = Collector.__new__(Collector)
    c.opt = RunOptions(category="mobiles", brands=["samsung"])
    c.ids, c.run_id, c._touched_products, c.stats = repo.id_maps(), None, {}, RunStats()
    c.store(listing("amazon.in", "B0CS5XW6TN", 74999))
    c.store(listing("poorvika.com", "samsung-galaxy-s24", 73999))
    repo.refresh_verification()

    cats = {x["slug"]: x["product_count"] for x in _call("list_categories", {})}
    assert cats["mobiles"] == 1

    found = _call("search_products", {"query": "galaxy", "category": "mobiles", "max_price": 80000})
    assert found["total"] == 1
    hit = found["products"][0]
    assert hit["best_price"] == "73999.00" and hit["best_price_site"] == "Poorvika"
    assert _call("search_products", {"max_price": 1000})["total"] == 0

    detail = _call("get_product", {"product_id": hit["product_id"]})
    assert {o["site"] for o in detail["offers"]} == {"Amazon.in", "Poorvika"}
    assert all(o["source_url"].startswith("https://") for o in detail["offers"])
    assert detail["image_urls"] == [] and detail["rating"] is None

    history = _call("price_history", {"product_id": hit["product_id"]})
    assert {h["price"] for h in history} == {"74999.00", "73999.00"}


def test_unknown_product_is_a_tool_error(db):
    import pytest
    from fastmcp.exceptions import ToolError

    with pytest.raises(ToolError, match="not found"):
        _call("get_product", {"product_id": 999999})