"""Illustrative in-memory JSON-RPC/stdio subset. NOT a complete MCP server.
No network, credentials, SDK, real tenant authentication or durable state.
The fixed fixture principal belongs to team-a. fault is test-only injection.
"""
import hashlib
import json
import sys

version = '2025-11-25'
initialized = False
negotiated = False
tickets = {'A-1': {'tenant': 'team-a', 'status': 'open', 'effects': 0}, 'A-2': {'tenant': 'team-a', 'status': 'open', 'effects': 0}, 'B-1': {'tenant': 'team-b', 'status': 'open', 'effects': 0}}
operations = {}


def error(code, message):
    return {'error': {'code': code, 'message': message}}


def result(value=None, failure=None):
    if failure:
        return {'result': {'content': [{'type': 'text', 'text': failure}], 'isError': True}}
    return {'result': {'content': [{'type': 'text', 'text': json.dumps(value)}], 'structuredContent': value, 'isError': False}}


def handle(req):
    global initialized, negotiated
    method = req.get('method')
    if method == 'initialize':
        negotiated = True
        return {'result': {'protocolVersion': version, 'capabilities': {'tools': {}}, 'serverInfo': {'name': 'article-safe-fixture', 'version': '0.1.0'}}}
    if method == 'notifications/initialized':
        initialized = negotiated
        return None
    if not initialized:
        return error(-32000, 'Fixture not initialized')
    if method == 'tools/list':
        definitions = []
        for name in ['get_ticket', 'close_ticket']:
            props = {'ticket_id': {'type': 'string'}}
            required = ['ticket_id']
            if name == 'close_ticket':
                props.update({'operation_key': {'type': 'string'}, 'fault': {'type': 'string', 'enum': ['after_write']}})
                required.append('operation_key')
            definitions.append({'name': name, 'description': 'Fictional local ticket fixture', 'inputSchema': {'type': 'object', 'properties': props, 'required': required, 'additionalProperties': False}})
        return {'result': {'tools': definitions}}
    if method != 'tools/call':
        return error(-32601, 'Method not in fixture profile')
    params = req.get('params', {})
    name, args = params.get('name'), params.get('arguments')
    if name not in ['get_ticket', 'close_ticket']:
        return error(-32602, 'Unknown fixture tool')
    allowed = {'ticket_id'} if name == 'get_ticket' else {'ticket_id', 'operation_key', 'fault'}
    if not isinstance(args, dict) or set(args) - allowed or not isinstance(args.get('ticket_id'), str):
        return result(failure='Invalid fixture arguments')
    ticket = tickets.get(args['ticket_id'])
    if not ticket or ticket['tenant'] != 'team-a':
        return result(failure='Access denied')
    if name == 'get_ticket':
        return result({'ticket_id': args['ticket_id'], **ticket})
    key = args.get('operation_key')
    if not isinstance(key, str) or not key or len(key) > 100 or args.get('fault') not in [None, 'after_write']:
        return result(failure='Invalid operation key or fault setting')
    digest = hashlib.sha256(json.dumps({'ticket_id': args['ticket_id'], 'status': 'closed'}, sort_keys=True).encode()).hexdigest()
    if key in operations:
        prior = operations[key]
        return result(prior['value']) if prior['digest'] == digest else result(failure='Operation key conflicts with changed intent')
    ticket['status'] = 'closed'
    ticket['effects'] += 1
    value = {'ticket_id': args['ticket_id'], 'status': 'closed', 'effects': ticket['effects']}
    operations[key] = {'digest': digest, 'value': value}
    if args.get('fault') == 'after_write':
        return result(failure='Simulated uncertain response after local effect; check state before retry')
    return result(value)


for line in sys.stdin:
    req = None
    try:
        req = json.loads(line)
        if not isinstance(req, dict) or req.get('jsonrpc') != '2.0' or not isinstance(req.get('method'), str):
            response = error(-32600, 'Invalid fixture request')
        else:
            response = handle(req)
        if isinstance(req, dict) and 'id' not in req:
            continue
        if response is not None:
            print(json.dumps({'jsonrpc': '2.0', 'id': req.get('id') if isinstance(req, dict) else None, **response}), flush=True)
    except json.JSONDecodeError:
        print(json.dumps({'jsonrpc': '2.0', 'id': None, **error(-32700, 'Invalid JSON')}), flush=True)