#!/usr/bin/env python3
"""
MCP server pro Firebird/Medicus — používá oficiální MCP SDK (FastMCP)
Spustit: python mcp_firebird.py
"""

import sys
import fdb
import traceback
from typing import Optional
from mcp.server.fastmcp import FastMCP

FB_CONFIG = {
    'dsn': r'localhost:c:\medicus 3\data\medicus.fdb',
    'user': 'SYSDBA',
    'password': 'masterkey',
    'charset': 'win1250',
    'port': 3070,
}

# Všechny logy MUSÍ jít na stderr — stdout je rezervován pro JSON-RPC
def log(msg: str):
    print(msg, file=sys.stderr, flush=True)


# Připojení k Firebirdu
try:
    conn = fdb.connect(**FB_CONFIG)
    log("✓ Připojeno k Firebirdu (Medicus)")
except Exception as e:
    log(f"✗ Chyba připojení k Firebirdu: {e}")
    sys.exit(1)


def rows_to_json(rows, description):
    """Převede fdb rows na JSON-serializovatelný formát"""
    import datetime
    import decimal

    def convert(val):
        if isinstance(val, (datetime.date, datetime.datetime)):
            return val.isoformat()
        if isinstance(val, decimal.Decimal):
            return float(val)
        if isinstance(val, bytes):
            return val.decode('win1250', errors='replace')
        return val

    cols = [d[0].strip() for d in description]
    return [dict(zip(cols, [convert(v) for v in row])) for row in rows]


# MCP server
mcp = FastMCP("medicus-firebird")


@mcp.tool()
def execute_query(sql: str, params: Optional[list] = None) -> dict:
    """Spusť SQL dotaz na Medicus databázi.
    Pro SELECT vrátí columns + rows. Pro INSERT/UPDATE/DELETE vrátí rowcount.
    """
    try:
        cur = conn.cursor()
        if params:
            cur.execute(sql, params)
        else:
            cur.execute(sql)

        if sql.strip().upper().startswith('SELECT'):
            rows = rows_to_json(cur.fetchall(), cur.description or [])
            return {
                'rowcount': len(rows),
                'rows': rows
            }
        else:
            conn.commit()
            return {
                'rowcount': cur.rowcount,
                'message': f'Dotaz proveden: {cur.rowcount} řádků ovlivněno'
            }
    except Exception as e:
        log(f"execute_query chyba: {traceback.format_exc()}")
        raise


@mcp.tool()
def list_tables() -> list[str]:
    """Vrátí seznam všech uživatelských tabulek v Medicus databázi."""
    try:
        cur = conn.cursor()
        cur.execute("""
            SELECT TRIM(RDB$RELATION_NAME)
            FROM RDB$RELATIONS
            WHERE RDB$SYSTEM_FLAG = 0
            ORDER BY RDB$RELATION_NAME
        """)
        return [row[0] for row in cur.fetchall()]
    except Exception as e:
        log(f"list_tables chyba: {traceback.format_exc()}")
        raise


@mcp.tool()
def get_table_columns(table_name: str) -> list[str]:
    """Vrátí seznam sloupců dané tabulky."""
    try:
        cur = conn.cursor()
        cur.execute("""
            SELECT TRIM(RDB$FIELD_NAME)
            FROM RDB$RELATION_FIELDS
            WHERE TRIM(RDB$RELATION_NAME) = ?
            ORDER BY RDB$FIELD_POSITION
        """, [table_name.upper()])
        return [row[0] for row in cur.fetchall()]
    except Exception as e:
        log(f"get_table_columns chyba: {traceback.format_exc()}")
        raise


@mcp.tool()
def get_schema() -> dict:
    """Vrátí kompletní schéma DB — všechny tabulky a jejich sloupce."""
    try:
        cur = conn.cursor()
        cur.execute("""
            SELECT r.RDB$RELATION_NAME, f.RDB$FIELD_NAME
            FROM RDB$RELATIONS r
            LEFT JOIN RDB$RELATION_FIELDS f ON r.RDB$RELATION_NAME = f.RDB$RELATION_NAME
            WHERE r.RDB$SYSTEM_FLAG = 0
            ORDER BY r.RDB$RELATION_NAME, f.RDB$FIELD_POSITION
        """)

        schema = {}
        for tbl_name, col_name in cur.fetchall():
            tbl = tbl_name.strip() if tbl_name else 'unknown'
            col = col_name.strip() if col_name else ''
            if tbl not in schema:
                schema[tbl] = []
            if col:
                schema[tbl].append(col)

        return {
            'table_count': len(schema),
            'tables': list(schema.keys()),
            'schema': schema
        }
    except Exception as e:
        log(f"get_schema chyba: {traceback.format_exc()}")
        raise


if __name__ == '__main__':
    log("MCP Firebird server spuštěn (FastMCP)")
    mcp.run()