{
 * Structures and functions to receive and process sensor events in
 * native code.
 *
}

Unit sensor;

Interface
Uses ctypes, looper;

{
 * Sensor types
 * (keep in sync with hardware/sensor.h)
 }
Const

  ASENSOR_TYPE_ACCELEROMETER      = 1;
  ASENSOR_TYPE_MAGNETIC_FIELD     = 2;
  ASENSOR_TYPE_GYROSCOPE          = 4;
  ASENSOR_TYPE_LIGHT              = 5;
  ASENSOR_TYPE_PROXIMITY          = 8;

// * Sensor accuracy measure
  ASENSOR_STATUS_UNRELIABLE       = 0;
  ASENSOR_STATUS_ACCURACY_LOW     = 1;
  ASENSOR_STATUS_ACCURACY_MEDIUM  = 2;
  ASENSOR_STATUS_ACCURACY_HIGH    = 3;

// * A few useful constants

// Earth's gravity in m/s^2
  ASENSOR_STANDARD_GRAVITY           = 9.80665;
// Maximum magnetic field on Earth's surface in uT
  ASENSOR_MAGNETIC_FIELD_EARTH_MAX   = 60.0;
// Minimum magnetic field on Earth's surface in uT
  ASENSOR_MAGNETIC_FIELD_EARTH_MIN   = 30.0;

// A sensor event.

Type
  ASensorVector = Packed Record
    x:Single;
    y:Single;
    z:Single;
    status:Shortint;
    reserved:Array[0..2] Of Byte;
  End;

  PASensorEvent = ^ASensorEvent;
  ASensorEvent = Packed Record
    version:Integer; // sizeof(struct ASensorEvent)
    sensor:Integer;
    _type:Integer;
    reserved0:Integer;
    timestamp:Int64;
    vector:ASensorVector;
(*        float           data[16];
        ASensorVector   vector;
        ASensorVector   acceleration;
        ASensorVector   magnetic;
        float           temperature;
        float           distance;
        float           light;
        float           pressure;
    };*)
    reserved1:Array[0..3]Of Integer;
  End;

  PASensorManager = ^ASensorManager;
  ASensorManager = Record End;

  PASensorEventQueue = ^ASensorEventQueue;
  ASensorEventQueue = Record End;

  PASensor =  ^ASensor;
  ASensor = Record End;

//typedef ASensor const* ASensorRef;
//typedef ASensorRef const* ASensorList;


// Get a reference to the sensor manager. ASensorManager is a singleton.
Function ASensorManager_getInstance():PASensorManager; cdecl; external;


// Returns the list of available sensors.
//Function ASensorManager_getSensorList(manager:PASensorManager; Var ASensorList* list);

// Returns the default sensor for the given type, or NULL if no sensor of that type exist.
Function ASensorManager_getDefaultSensor(manager:PASensorManager; _type:Integer):PASensor; cdecl; external;

// Creates a new sensor event queue and associate it with a looper.
Function ASensorManager_createEventQueue(manager:PASensorManager; looper:PALooper; ident:Integer; callback:ALooper_callbackFunc; data:Pointer):PASensorEventQueue; cdecl; external;

// Destroys the event queue and free all resources associated to it.
Function ASensorManager_destroyEventQueue(manager:PASensorManager; queue:ASensorEventQueue):Integer; cdecl; external;


// Enable the selected sensor. Returns a negative error code on failure.
Function ASensorEventQueue_enableSensor(queue:PASensorEventQueue; sensor:PASensor):Integer; cdecl; external;

// Disable the selected sensor. Returns a negative error code on failure.
Function ASensorEventQueue_disableSensor(queue:PASensorEventQueue; sensor:PASensor):Integer; cdecl; external;

(*
 * Sets the delivery rate of events in microseconds for the given sensor.
 * Note that this is a hint only, generally event will arrive at a higher
 * rate. It is an error to set a rate inferior to the value returned by
 * ASensor_getMinDelay().
 * Returns a negative error code on failure.
 *)
Function ASensorEventQueue_setEventRate(queue:PASensorEventQueue; sensor:PASensor; usec:Integer):Integer; cdecl; external;

(*
 * Returns true if there are one or more events available in the
 * sensor queue.  Returns 1 if the queue has events; 0 if
 * it does not have events; and a negative value if there is an error.
 *)
Function ASensorEventQueue_hasEvents(queue:ASensorEventQueue):Integer; cdecl; external;

(*
 * Returns the next available events from the queue.  Returns a negative
 * value if no events are available or an error has occurred, otherwise
 * the number of events returned.
 *
 * Examples:
 *   ASensorEvent event;
 *   ssize_t numEvent = ASensorEventQueue_getEvents(queue, &event, 1);
 *
 *   ASensorEvent eventBuffer[8];
 *   ssize_t numEvent = ASensorEventQueue_getEvents(queue, eventBuffer, 8);
 *
 *)
Function ASensorEventQueue_getEvents(queue:PASensorEventQueue; events:PASensorEvent; count:csize_t):csize_t; cdecl; external;

// Returns this sensor's name (non localized)
Function ASensor_getName(sensor:PASensor):PChar; cdecl; external;

// Returns this sensor's vendor's name (non localized)
Function ASensor_getVendor(sensor:PASensor):PChar; cdecl; external;

// Return this sensor's type
Function ASensor_getType(sensor:PASensor):Integer; cdecl; external;

// Returns this sensors's resolution
Function ASensor_getResolution(sensor:PASensor):Single; cdecl; external;

(*
 * Returns the minimum delay allowed between events in microseconds.
 * A value of zero means that this sensor doesn't report events at a
 * constant rate, but rather only when a new data is available.
 *)
Function ASensor_getMinDelay(sensor:PASensor):Integer; cdecl; external;

Implementation

End.