"""Map wM-Bus 3-letter FLAG manufacturer codes to full names.

The DLL header only carries the 3-letter FLAG code (e.g. "KAM"). This is a
best-effort lookup of common metering manufacturers; unknown codes fall back
to the code itself.
"""

_FLAG = {
    "ABB": "ABB",
    "AMT": "Aquametro",
    "APA": "Apator",
    "APT": "Apator",
    "BME": "BMeters",
    "BME": "BMeters",
    "DME": "Diehl Metering",
    "DWZ": "Lorenz",
    "EFE": "Engelmann",
    "ELS": "Elster",
    "ELV": "Elvaco",
    "EMH": "EMH Metering",
    "ESY": "EasyMeter",
    "GAV": "Carlo Gavazzi",
    "GWF": "GWF",
    "HYD": "Diehl (Hydrometer)",
    "INE": "Innotas",
    "ITW": "Itron",
    "ITR": "Itron",
    "KAM": "Kamstrup",
    "KAW": "Kamstrup",
    "LUG": "Landis+Gyr",
    "LGB": "Landis+Gyr",
    "MAD": "Maddalena",
    "MTR": "Metrona",
    "NZR": "NZR",
    "QDS": "Qundis",
    "REL": "Relay",
    "RKE": "Viterra / Ista",
    "SAP": "Sappel",
    "SEN": "Sensus",
    "SON": "Sontex",
    "SPX": "Spanner-Pollux",
    "TCH": "Techem",
    "WEP": "Weptech",
    "ZRI": "Zenner",
}


def manufacturer_name(code: str) -> str:
    if not code:
        return ""
    return _FLAG.get(code.upper(), code.upper())