// Copyright 2018 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.hardware.powersource;
using zx;

type PowerType = strict enum : uint8 {
    AC = 0;
    BATTERY = 1;
};

const POWER_STATE_ONLINE uint8 = 0x1;
const POWER_STATE_DISCHARGING uint8 = 0x2;
const POWER_STATE_CHARGING uint8 = 0x4;
const POWER_STATE_CRITICAL uint8 = 0x8;

type SourceInfo = struct {
    type PowerType;
    state uint8;
};

type BatteryUnit = strict enum {
    /// Milliwatts
    MW = 0;
    /// Milliamps
    MA = 1;
};

type BatteryInfo = struct {
    /// capacity unit. all voltage fields are in millivolts
    unit BatteryUnit;
    /// nominal capacity of a new battery
    design_capacity uint32;
    /// predicted battery capacity when fully charged
    last_full_capacity uint32;
    /// nominal voltage of a new battery
    design_voltage uint32;
    /// capacity when the device will generate a warning notification
    capacity_warning uint32;
    /// capacity when the device will generate a low battery notification
    capacity_low uint32;
    /// the smallest increment the battery is capable of measuring between the
    /// low and warning capacities
    capacity_granularity_low_warning uint32;
    /// the smallest increment the battery is capable of measuring between the low
    /// and warning capacities
    capacity_granularity_warning_full uint32;

    /// below fields are in units specified the `unit` field.
    /// charging/discharging rate in the capacity unit. positive is charging,
    /// negative is discharging
    present_rate int32;
    remaining_capacity uint32;
    present_voltage uint32;
};

closed protocol Source {
    /// Get device info.
    strict GetPowerInfo() -> (struct {
        status zx.Status;
        info SourceInfo;
    });

    /// Get an event to receive state change notifications on. ZX_USER_SIGNAL_0 is
    /// asserted when power_info_t.state is changed. It is deasserted when the
    /// state is read via `GetPowerInfo`.
    strict GetStateChangeEvent() -> (resource struct {
        status zx.Status;
        handle zx.Handle:<EVENT, zx.Rights.WAIT>;
    });

    /// Get battery info. Only supported if type == PowerType::BATTERY.
    strict GetBatteryInfo() -> (struct {
        status zx.Status;
        info BatteryInfo;
    });
};