from __future__ import annotations

import base64
import hashlib
from datetime import datetime, timedelta, timezone
from pathlib import Path

import pytest
from fastapi.testclient import TestClient
from sqlalchemy import select

from app.container import build_container
from app.core.config import Settings
from app.mcp.registry import MCPRegistry
from app.security.context import auth_context
from app.security.errors import APIKeyConflictError, ForbiddenError, RateLimitError, UnauthorizedError
from app.security.models import APIKey, AuditLog
from app.security.schemas import APIKeyCreate
from app.security.service import APIKeyService
from main import create_app


def security_settings(tmp_path: Path, **overrides: object) -> Settings:
    values: dict[str, object] = {
        "_env_file": None,
        "temp_dir": tmp_path / "temp",
        "output_dir": tmp_path / "outputs",
        "database_url": f"sqlite+aiosqlite:///{tmp_path / 'security.db'}",
        "auth_enabled": True,
        "auth_last_used_update_seconds": 0,
        "cleanup_interval_seconds": 3600,
        "whisper_model": "tiny",
        "max_workers": 1,
    }
    values.update(overrides)
    return Settings(**values)


@pytest.fixture
async def security_container(tmp_path: Path):
    container = build_container(security_settings(tmp_path))
    await container.security_database.initialize()
    try:
        yield container
    finally:
        await container.security_database.close()


async def create_key(container, **overrides: object) -> tuple[APIKey, str]:
    values: dict[str, object] = {
        "name": "Automation",
        "environment": "test",
        "role": None,
        "scopes": ["templates:read"],
    }
    values.update(overrides)
    return await container.api_keys.create(APIKeyCreate(**values), created_by="tests")


async def test_key_generation_has_256_bits_and_database_never_stores_secret(
    security_container,
) -> None:
    record, secret = await create_key(security_container)

    environment, encoded_secret = secret.split("_", 2)[1:]
    raw_secret = base64.urlsafe_b64decode(encoded_secret + "=")
    assert environment == "test"
    assert len(raw_secret) == 32
    assert record.key_prefix == f"mp_test_{encoded_secret[:8]}"
    assert record.key_hash == hashlib.sha256(secret.encode()).hexdigest()

    async with security_container.security_database.session() as session:
        stored = await session.get(APIKey, record.id)
        assert stored is not None
        assert secret not in vars(stored).values()
        assert not hasattr(stored, "api_key")


async def test_authentication_rejects_invalid_expired_disabled_and_revoked_keys(
    security_container,
) -> None:
    active, active_secret = await create_key(security_container)
    assert (await security_container.api_keys.authenticate(active_secret)).api_key_id == active.id

    replacement = "A" if active_secret[-1] != "A" else "B"
    with pytest.raises(UnauthorizedError):
        await security_container.api_keys.authenticate(active_secret[:-1] + replacement)

    _, expired_secret = await create_key(
        security_container,
        name="Expired",
        expires_at=datetime.now(timezone.utc) - timedelta(seconds=1),
    )
    with pytest.raises(UnauthorizedError):
        await security_container.api_keys.authenticate(expired_secret)

    await security_container.api_keys.set_status(active.id, "disabled")
    with pytest.raises(UnauthorizedError):
        await security_container.api_keys.authenticate(active_secret)
    await security_container.api_keys.set_status(active.id, "active")
    assert (await security_container.api_keys.authenticate(active_secret)).api_key_id == active.id

    await security_container.api_keys.set_status(active.id, "revoked")
    with pytest.raises(UnauthorizedError):
        await security_container.api_keys.authenticate(active_secret)
    with pytest.raises(APIKeyConflictError):
        await security_container.api_keys.set_status(active.id, "disabled")
    with pytest.raises(APIKeyConflictError):
        await security_container.api_keys.set_status(active.id, "active")


async def test_scope_enforcement_and_rotation_grace_period(security_container) -> None:
    old, old_secret = await create_key(security_container)
    context = await security_container.api_keys.authenticate(old_secret)
    security_container.api_keys.authorize(context, "templates:read")
    with pytest.raises(ForbiddenError):
        security_container.api_keys.authorize(context, "operations:execute")

    replacement, replacement_secret = await security_container.api_keys.rotate(
        old.id, 60, created_by="tests"
    )
    assert replacement.rotated_from_id == old.id
    assert (await security_container.api_keys.authenticate(old_secret)).api_key_id == old.id
    assert (
        await security_container.api_keys.authenticate(replacement_secret)
    ).api_key_id == replacement.id
    with pytest.raises(APIKeyConflictError):
        await security_container.api_keys.set_status(old.id, "disabled")

    async with security_container.security_database.session() as session:
        rotating = await session.get(APIKey, old.id)
        assert rotating is not None
        rotating.grace_expires_at = datetime.now(timezone.utc) - timedelta(seconds=1)
        await session.commit()
    with pytest.raises(UnauthorizedError):
        await security_container.api_keys.authenticate(old_secret)
    assert (await security_container.api_keys.get(old.id)).status == "revoked"


async def test_per_key_request_and_concurrent_job_limits(security_container) -> None:
    _, request_secret = await create_key(
        security_container, name="RPM", requests_per_minute=1
    )
    request_context = await security_container.api_keys.authenticate(request_secret)
    lease = await security_container.rate_limiter.acquire(
        request_context, is_job=False, is_upload=False, uploaded_bytes=0
    )
    await lease.release()
    with pytest.raises(RateLimitError) as rate_error:
        await security_container.rate_limiter.acquire(
            request_context, is_job=False, is_upload=False, uploaded_bytes=0
        )
    assert rate_error.value.retry_after >= 1

    _, job_secret = await create_key(
        security_container, name="Concurrency", concurrent_jobs=1
    )
    job_context = await security_container.api_keys.authenticate(job_secret)
    running = await security_container.rate_limiter.acquire(
        job_context, is_job=True, is_upload=False, uploaded_bytes=0
    )
    with pytest.raises(RateLimitError):
        await security_container.rate_limiter.acquire(
            job_context, is_job=True, is_upload=False, uploaded_bytes=0
        )
    await running.release()
    next_job = await security_container.rate_limiter.acquire(
        job_context, is_job=True, is_upload=False, uploaded_bytes=0
    )
    await next_job.release()


async def test_stdio_mcp_uses_shared_context_scopes_rate_limits_and_audit(
    security_container,
) -> None:
    _, secret = await create_key(
        security_container, name="MCP Reader", scopes=["mcp:read"]
    )
    context = await security_container.api_keys.authenticate(secret)
    registry = MCPRegistry(security_container)
    unauthorized = await registry.run_metadata_tool("system_info", registry.system_info_data)
    token = auth_context.set(context)
    try:
        resource = await registry.safe_resource("version", registry.version_data)
        forbidden = await registry.run_metadata_tool("system_info", registry.system_info_data)
    finally:
        auth_context.reset(token)

    assert unauthorized["success"] is False
    assert unauthorized["error"]["code"] == "UNAUTHORIZED"
    assert resource["success"] is True
    assert forbidden["success"] is False
    assert forbidden["error"]["code"] == "FORBIDDEN"
    async with security_container.security_database.session() as session:
        logs = list((await session.scalars(select(AuditLog))).all())
    assert {log.endpoint for log in logs} >= {
        "mcp://tools/resource.version",
        "mcp://tools/system_info",
    }


def test_http_middleware_public_and_authentication_contracts(tmp_path: Path) -> None:
    material = APIKeyService.generate_material("test")
    settings = security_settings(
        tmp_path,
        auth_bootstrap_key_hash=material.key_hash,
        auth_bootstrap_key_prefix=material.key_prefix,
        auth_bootstrap_environment="test",
        auth_default_requests_per_minute=1000,
    )
    application = create_app(settings)
    authorization = {"Authorization": f"Bearer {material.api_key}"}

    with TestClient(application) as client:
        for path in ("/", "/health", "/version", "/docs", "/openapi.json", "/redoc"):
            assert client.get(path).status_code == 200

        missing = client.get("/v1/auth/context")
        malformed = client.get(
            "/v1/auth/context", headers={"Authorization": "Basic not-a-mediarouter-key"}
        )
        invalid = client.get(
            "/v1/auth/context", headers={"Authorization": "Bearer mp_test_invalid"}
        )
        for response in (missing, malformed, invalid):
            assert response.status_code == 401
            assert response.json() == {
                "error": "Unauthorized",
                "message": "Invalid or expired API key.",
            }
            assert response.headers["www-authenticate"] == "Bearer"

        mcp_missing = client.post("/mcp/", json={"jsonrpc": "2.0", "id": 1})
        assert mcp_missing.status_code == 401

        identity = client.get("/v1/auth/context", headers=authorization)
        assert identity.status_code == 200
        assert identity.json()["key_prefix"] == material.key_prefix
        assert "admin" in identity.json()["scopes"]

        created = client.post(
            "/v1/api-keys",
            headers=authorization,
            json={
                "name": "Template Reader",
                "environment": "test",
                "role": None,
                "scopes": ["templates:read"],
            },
        )
        assert created.status_code == 201
        limited_authorization = {
            "Authorization": f"Bearer {created.json()['api_key']}"
        }
        assert client.get("/v1/auth/context", headers=limited_authorization).status_code == 200
        forbidden = client.get("/v1/health", headers=limited_authorization)
        assert forbidden.status_code == 403
        assert forbidden.json() == {
            "error": "Forbidden",
            "message": "Missing required scope.",
        }

        mcp_forbidden = client.post(
            "/mcp/",
            headers=limited_authorization,
            json={
                "jsonrpc": "2.0",
                "id": 1,
                "method": "tools/call",
                "params": {"name": "health", "arguments": {}},
            },
        )
        assert mcp_forbidden.status_code == 403

        audit_logs = client.get("/v1/audit-logs", headers=authorization)
        assert audit_logs.status_code == 200
        entries = audit_logs.json()
        assert any(
            entry["endpoint"] == "/v1/auth/context"
            and entry["api_key_id"] == identity.json()["id"]
            and entry["response_code"] == 200
            for entry in entries
        )


def test_http_rate_limit_returns_retry_after(tmp_path: Path) -> None:
    material = APIKeyService.generate_material("test")
    application = create_app(
        security_settings(
            tmp_path,
            auth_bootstrap_key_hash=material.key_hash,
            auth_bootstrap_key_prefix=material.key_prefix,
            auth_bootstrap_environment="test",
            auth_default_requests_per_minute=1,
        )
    )
    headers = {"Authorization": f"Bearer {material.api_key}"}
    with TestClient(application) as client:
        assert client.get("/v1/auth/context", headers=headers).status_code == 200
        limited = client.get("/v1/auth/context", headers=headers)

    assert limited.status_code == 429
    assert limited.json() == {
        "error": "Rate limit exceeded",
        "message": "Retry later.",
    }
    assert int(limited.headers["retry-after"]) >= 1