/*
 * Copyright 2017 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package android.hardware.wifi.offload@1.0;

/**
 * Defines a bitmap of security modes
 */
enum SecurityMode : uint8_t {
    OPEN                    = 0x1 << 1,
    WEP                     = 0x1 << 2,
    PSK                     = 0x1 << 3,
    EAP                     = 0x1 << 4,
};

/**
 * SSID of the Access Point, maximum 32 characters
 */
typedef vec<uint8_t> Ssid;

/**
 * Preferred network information
 * SSID and associated security mode(s)
 */
struct NetworkInfo {
    Ssid ssid;
    /* SecurityMode flags that are associated with this SSID
     * More than one security mode can be supported, see SecurityMode */
    bitfield<SecurityMode> flags;
};

/**
 * This is a bit mask describing the capabilities of a BSS.
 * See IEEE Std 802.11: 8.4.1.4
 */
enum Capability : uint16_t {
    ESS                     = 1 << 0,
    IBSS                    = 1 << 1,
    CF_POLLABLE             = 1 << 2,
    CF_PLL_REQ              = 1 << 3,
    PRIVACY                 = 1 << 4,
    SHORT_PREAMBLE          = 1 << 5,
    PBCC                    = 1 << 6,
    CHANNEL_AGILITY         = 1 << 7,
    SPECTURM_MGMT           = 1 << 8,
    QOS                     = 1 << 9,
    SHORT_SLOT_TIME         = 1 << 10,
    APSD                    = 1 << 11,
    RADIO_MEASUREMENT       = 1 << 12,
    DSSS_OFDM               = 1 << 13,
    DELAYED_BLOCK_ACK       = 1 << 14,
    IMMEDIATE_BLOCK_ACK     = 1 << 15,
};

/**
 * Scan Results returned by the offload Hal
 */
struct ScanResult {
    /* Information about this BSS
     * SSID and security modes supported */
    NetworkInfo networkInfo;
    /* BSSID of the BSS */
    uint8_t[6] bssid;
    /* Can have multiple bits set, see Capability */
    bitfield<Capability> capability;
    /* Frequency scanned, in mHz */
    uint32_t frequency;
    /* Signal strength in dBm */
    int8_t rssi;
    /* TSF found in beacon/probe response */
    uint64_t tsf;
};


/**
 * Parameters for performing offload scans
 */
struct ScanParam {
    /* Specify a list of SSIDs to scan, an empty list implies no preferred
     * networks to scan */
    vec<Ssid> ssidList;
    /* Frequencies to scan, in mHz, an empty frequency list implies a full scan */
    vec<uint32_t> frequencyList;
    /* Periodicity of the scans to be performed by the offload module
     * A value of zero indicates disable periodic scans. For this revision,
     * where offload module is performing scans in disconnected mode, this value
     * should not be zero. In future versions, periodic scans can be eliminated */
    uint32_t disconnectedModeScanIntervalMs;
};

/**
 * Instruction on how to filter the scan result before performing network
 * selection and waking up the AP to connect
 */
struct ScanFilter {
    /* Preferred network List of SSIDs and their security mode of interest
     * The filter will drop the remaining scan results in the scan event.
     * An empty list implies no filtering of scan result based on SSID and
     * security mode. */
    vec<NetworkInfo> preferredNetworkInfoList;
    /* Minimum qualifying RSSI to be considered for network selection (dBm) */
    int8_t rssiThreshold;
};

struct ScanRecord {
    /* Amount of time spent scanning */
    uint64_t durationMs;
    /* Number of channels scanned */
    uint32_t numChannelsScanned;
    /* Number of entries aggregated into this record */
    uint32_t numEntriesAggregated;
};

/**
 * Enumerates the type of log that is recorded
 */
enum RecordName : uint32_t {
    CMD_BASE                        = 0x00001000,
    /* Record name corresponding to initialization */
    CMD_INT                         = CMD_BASE + 0,
   /* Record name corresponding to configureScans() API */
    CMD_CONFIG_SCANS                = CMD_BASE + 1,
    /* Record name corresponding to subscribeScanResults() API */
    CMD_SUBSCRIBE_SCAN_RESULTS      = CMD_BASE + 2,
    /* Record name corresponding to unsubscribeScanResults() API */
    CMD_UNSUBSCRIBE_SCAN_RESULTS    = CMD_BASE + 3,
    /* Record name corresponding to getScanStats() API */
    CMD_GET_SCAN_STATS              = CMD_BASE + 4,
    /* Record name corresponding to a reset*/
    CMD_RESET                       = CMD_BASE + 5,
    /* Add new commands here */
    EVENT_RECVD_BASE                = 0x00002000,
    /* Record name corresponding to scan monitor event*/
    EVENT_RECVD_SCAN_RESULT_ASYNC   = EVENT_RECVD_BASE + 0,
    /* Record name corresponding to scan response event */
    EVENT_RECVD_SCAN_RESULT         = EVENT_RECVD_BASE + 1,
    /* Add new events received here */
    EVENT_SENT_BASE                 = 0x00003000,
    /* Record name corresponding to scan event sent */
    EVENT_SENT_SCAN_RESULT          = EVENT_SENT_BASE + 0,
    /* Record name corresponding to abort event sent */
    EVENT_SENT_ABORT                = EVENT_SENT_BASE + 1,
    /* Record name corresponding to error event sent */
    EVENT_SENT_ERROR                = EVENT_SENT_BASE + 2,
    /* Add new events sent here */
    REQ_BASE                        = 0x00004000,
    /* Record name corresponding to scan request sent*/
    REQ_SCAN                        = REQ_BASE + 0,
    /* Add new requests here */
};

/**
 * Defines the structure of each log record
 */
struct LogRecord {
    /* Indicates the log recorded */
    RecordName recordName;
    /* Platform reference time in milliseconds when the log is recorded */
    uint64_t logTimeMs;
};

/**
 * Defines the scan statistics to be returned to the framework
 */
struct ScanStats {
    /* Incremented everytime a new scan is requested */
    uint32_t numScansRequestedByWifi;
    /* Incremented everytime the scan is serviced by performing a scan*/
    uint32_t numScansServicedByWifi;
    /* Incremented everytime the scan is serviced by the scan cache */
    uint32_t numScansServicedbyCache;
    /* The last (CHRE reference) time this data structure is updated */
    uint64_t lastUpdated;
    /* The last (CHRE reference) time this data structure is read */
    uint64_t lastRead;
    /* The total time when the Offload module could be performing scans (T2 - T1)
     * T1 - time when the framework subscribes for scan result (includes delayMs)
     * T2 - min (time when the framework unsubscribes for scan result,
     * currentTime) */
    uint64_t subscriptionDurationMs;
    /* Histograms of the channels scanned, 802.11 and with an 8 bit
     * representation, only 256 channels are available */
    uint8_t[256] histogramChannelsScanned;
    /* Scan Record for this subscribe duration */
    vec<ScanRecord> scanRecord;
    /* Vector of the logRecord entries */
    vec<LogRecord> logRecord;
};

/**
 * Defines a list of return codes to indicate status of Offload HAL
 */
enum OffloadStatusCode : uint32_t {
    /* No error */
    OK,
    /* No Connection to underlying implementation */
    NO_CONNECTION,
    /* Operation timeout */
    TIMEOUT,
    /* Other errors */
    ERROR
};

/**
 * Generic structures to return the status of an operation
 */
struct OffloadStatus {
  OffloadStatusCode code;
  /* Error message */
  string description;
};