// Copyright 2021 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
library fuchsia.wlan.internal;

using fuchsia.wlan.common;
using fuchsia.wlan.ieee80211 as ieee80211;

type BssType = strict enum {
    // The UNKNOWN value is added to this type instead of created a new
    // enum like `DetectedBssType` so that language bindings can avoid the use
    // of verbose constants like DETECTED_BSS_TYPE_INFRASTRUCTURE. The tradeoff
    // is to handle UNKNOWN when specifying the BSS type of a new AP.
    UNKNOWN = 0;

    INFRASTRUCTURE = 1;
    INDEPENDENT = 2;
    MESH = 3;
    PERSONAL = 4;
};

type BssConfig = struct {
    bssid ieee80211.MacAddr;
    bss_type BssType;
    remote bool;
};

// IEEE Std 802.11-2016, 9.4.1.4
alias CapabilityInfo = uint16;

// IEEE Std 802.11-2016 9.4.2.56
@namespaced
const HT_CAP_LEN uint8 = 26;

// IEEE Std 802.11-2016 9.4.2.57
@namespaced
const HT_OP_LEN uint8 = 22;

// IEEE Std 802.11-2016 9.5.2.158
@namespaced
const VHT_CAP_LEN uint8 = 12;

// IEEE Std 802.11-2016 9.5.2.159
@namespaced
const VHT_OP_LEN uint8 = 5;

// IEEE Std 802.11-2016 defines 12 values in dot11SupportedDataRatesRxTable.
// It is never necessary to report more than 12 basic rates.
//
// This constant is strictly meant to bound the number of supported basic rates
// communicated between WLAN components.
@namespaced
const MAX_SUPPORTED_BASIC_RATES uint8 = 12;

// IEEE Std 802.11-2016 defines 12 values in dot11SupportedDataRatesRxTable and
// 2 values for BSS Membership Selector in Table 9-78. The number of valid basic rates
// specified in the Beacon frame received from an AP is therefore bounded by 14.
//
// This constant is strictly meant to bound the number of basic rates communicated
// between WLAN components during association.
@namespaced
const MAX_ASSOC_BASIC_RATES uint8 = 14;

// IEEE Std 802.11-2016 9.4.2.56
type HtCapabilities = struct {
    bytes array<uint8, HT_CAP_LEN>;
};

// IEEE Std 802.11-2016 9.4.2.57
type HtOperation = struct {
    bytes array<uint8, HT_OP_LEN>;
};

// IEEE Std 802.11-2016 9.5.2.158
type VhtCapabilities = struct {
    bytes array<uint8, VHT_CAP_LEN>;
};

// IEEE Std 802.11-2016 9.5.2.159
type VhtOperation = struct {
    bytes array<uint8, VHT_OP_LEN>;
};

// IEEE Std 802.11-2016 6.3.3.3.2
type BssDescription = struct {
    bssid ieee80211.MacAddr;

    bss_type BssType;
    beacon_period uint16; // in TU
    capability_info CapabilityInfo;

    /// All info elements present in the beacon or probe response frame.
    ies bytes;

    // List up non-standard, Fuchsia only parameters
    channel fuchsia.wlan.common.WlanChannel;
    // The running average of received signal strength indicator in units of dBm. This value is
    // updated periodically when the client is associated to an AP.
    rssi_dbm int8; // dBm
    // The running average of snr in units of dB. This value is updated periodically when the
    // client is associated to an AP.
    snr_db int8;
};

type WmmStatusResponse = struct {
    apsd bool;
    ac_be_params WmmAcParams;
    ac_bk_params WmmAcParams;
    ac_vi_params WmmAcParams;
    ac_vo_params WmmAcParams;
};

/// WFA WMM v1.2, 2.2.2
type WmmAcParams = struct {
    /// Lower bound of contention window in exponential form
    /// `cw_min = 2^(ecw_min) - 1`. The unit for contention window is "slot time", which
    /// is different for each standard (e.g. 9 microseconds, 13 microseconds, etc.)
    ecw_min uint8;
    /// Upper bound of contention window in exponential form
    /// `cw_max = 2^(ecw_max) - 1`. The unit for contention window is "slot time", which
    /// is different for each standard (e.g. 9 microseconds, 13 microseconds, etc.)
    ecw_max uint8;
    /// Arbitration Interframe Spacing Number (control wait time between sending each frame)
    aifsn uint8;
    /// TXOP limit in unit of 32 microseconds
    txop_limit uint16;
    /// Whether admission control is mandatory
    acm bool;
};

type SignalReportIndication = struct {
    rssi_dbm int8;
    snr_db int8;
};

// IEEE 802.11-2016 9.4.2.19
// Unlike a normal channel switch announcement, a ChannelSwitchInfo is sent at the time the channel
// changes and does not include a delay field.
type ChannelSwitchInfo = struct {
    new_channel uint8;
    // The operating class/country may also be modified by an extended channel switch request, but
    // we do not currently support this.
};