room_price_calc/mcp_server.py

import json
import os
from mcp.server.fastmcp import FastMCP

_here = os.path.dirname(__file__)

with open(os.path.join(_here, "config.json")) as f:
  _config = json.load(f)

SERVICES = _config['services']
SALES_TAX = _config['global']['taxes']['sales']

mcp = FastMCP("room-price-calc")

def _dollar(v: float) -> str:
  return "{:.2f}".format(round(v, 2))

def _details_fmt(details: dict) -> dict:
  return {k.replace('_', ' ').title(): _dollar(v) for k, v in details.items()}

def _resolve_service(service: str):
  svc = SERVICES.get(service.lower().strip())
  if svc is None:
    keys = ', '.join(SERVICES.keys())
    raise ValueError(f"Unknown service '{service}'. Valid keys: {keys}")
  return svc

def _n2l(svc, net, det):
  comm_rate = svc.get('fees', {}).get('commission', 0)
  wrong_rate = svc.get('taxes', {}).get('wrong', SALES_TAX)
  list_ = net / (1 - comm_rate - SALES_TAX + wrong_rate)
  if 'fees' in svc and 'commission' in svc['fees']:
    det['commission'] = list_ * comm_rate
  if 'taxes' in svc and 'wrong' in svc['taxes']:
    det['wrong_tax'] = list_ * wrong_rate
    det['sales_tax'] = list_ * SALES_TAX
    det['wrong_tax_loss'] = det['sales_tax'] - det['wrong_tax']
  return round(list_, 2)

def _l2n(svc, list_, det):
  net = list_
  if 'fees' in svc and 'commission' in svc['fees']:
    det['commission'] = net * svc['fees']['commission']
  if 'taxes' in svc and 'wrong' in svc['taxes']:
    det['sales_tax'] = net * SALES_TAX
    det['wrong_tax'] = net * svc['taxes']['wrong']
    det['wrong_tax_loss'] = det['sales_tax'] - det['wrong_tax']
  for k in ['commission', 'wrong_tax_loss']:
    if k in det:
      net -= det[k]
  return round(net, 2)

def _l2r(svc, list_, det):
  retail = list_
  if 'fees' in svc and 'client_fee' in svc['fees']:
    det['client_fee'] = retail * svc['fees']['client_fee']
    retail += det['client_fee']
  if 'taxes' in svc and 'wrong' in svc['taxes']:
    det['wrong_tax'] = retail * svc['taxes']['wrong']
    retail += det['wrong_tax']
  else:
    det['sales_tax'] = retail * SALES_TAX
    retail += det['sales_tax']
  if 'taxes' in svc and 'flat_tax' in svc['taxes']:
    det['service_tax'] = svc['taxes']['flat_tax']
    retail += det['service_tax']
  return round(retail, 2)

def _r2l(svc, retail, det):
  list_ = retail
  if 'taxes' in svc and 'flat_tax' in svc['taxes']:
    det['service_tax'] = svc['taxes']['flat_tax']
    list_ -= det['service_tax']
  if 'taxes' in svc and 'wrong' in svc['taxes']:
    det['wrong_tax'] = list_ - (list_ / (1 + svc['taxes']['wrong']))
    list_ -= det['wrong_tax']
  else:
    det['sales_tax'] = list_ - (list_ / (1 + SALES_TAX))
    list_ -= det['sales_tax']
  if 'fees' in svc and 'client_fee' in svc['fees']:
    det['client_fee'] = list_ - (list_ / (1 + svc['fees']['client_fee']))
    list_ -= det['client_fee']
  return round(list_, 2)

def _result(service_key, **amounts) -> dict:
  det = {k: _dollar(v) for k, v in amounts.items() if k != 'details'}
  return {'service': service_key, **det}

@mcp.tool()
def list_services() -> list:
  """List all available booking services with their keys and display names."""
  return [{'key': k, 'name': v['name']} for k, v in SERVICES.items()]

@mcp.tool()
def net_to_list(service: str, amount: float) -> dict:
  """Convert a net (owner payout) amount to the list (booking) price for a service.

  Args:
    service: Service key (e.g. 'airbnb', 'booking')
    amount: Net amount in dollars
  """
  svc = _resolve_service(service)
  det = {}
  list_ = _n2l(svc, amount, det)
  return {'service': service, 'net': _dollar(amount), 'list': _dollar(list_), 'details': _details_fmt(det)}

@mcp.tool()
def list_to_net(service: str, amount: float) -> dict:
  """Convert a list (booking) price to the net (owner payout) amount for a service.

  Args:
    service: Service key (e.g. 'airbnb', 'booking')
    amount: List price in dollars
  """
  svc = _resolve_service(service)
  det = {}
  net = _l2n(svc, amount, det)
  return {'service': service, 'list': _dollar(amount), 'net': _dollar(net), 'details': _details_fmt(det)}

@mcp.tool()
def list_to_retail(service: str, amount: float) -> dict:
  """Convert a list (booking) price to the retail (guest-facing) price for a service.

  Args:
    service: Service key (e.g. 'airbnb', 'booking')
    amount: List price in dollars
  """
  svc = _resolve_service(service)
  det = {}
  retail = _l2r(svc, amount, det)
  return {'service': service, 'list': _dollar(amount), 'retail': _dollar(retail), 'details': _details_fmt(det)}

@mcp.tool()
def retail_to_list(service: str, amount: float) -> dict:
  """Convert a retail (guest-facing) price to the list (booking) price for a service.

  Args:
    service: Service key (e.g. 'airbnb', 'booking')
    amount: Retail price in dollars
  """
  svc = _resolve_service(service)
  det = {}
  list_ = _r2l(svc, amount, det)
  return {'service': service, 'retail': _dollar(amount), 'list': _dollar(list_), 'details': _details_fmt(det)}

@mcp.tool()
def net_to_retail(service: str, amount: float) -> dict:
  """Convert a net (owner payout) amount to the retail (guest-facing) price for a service.

  Args:
    service: Service key (e.g. 'airbnb', 'booking')
    amount: Net amount in dollars
  """
  svc = _resolve_service(service)
  det = {}
  list_ = _n2l(svc, amount, det)
  det2 = {}
  retail = _l2r(svc, list_, det2)
  det.update(det2)
  return {'service': service, 'net': _dollar(amount), 'list': _dollar(list_), 'retail': _dollar(retail), 'details': _details_fmt(det)}

@mcp.tool()
def retail_to_net(service: str, amount: float) -> dict:
  """Convert a retail (guest-facing) price to the net (owner payout) amount for a service.

  Args:
    service: Service key (e.g. 'airbnb', 'booking')
    amount: Retail price in dollars
  """
  svc = _resolve_service(service)
  det = {}
  list_ = _r2l(svc, amount, det)
  det2 = {}
  net = _l2n(svc, list_, det2)
  det.update(det2)
  return {'service': service, 'retail': _dollar(amount), 'list': _dollar(list_), 'net': _dollar(net), 'details': _details_fmt(det)}

if __name__ == "__main__":
  mcp.run()