source: orbit/iOS/Orbit/Orbit/ViewController.m @ 067ea71

//
//  ViewController.m
//  Orbit
//
//  Copyright (c) 2012 Puzzlebox Productions, LLC. All rights reserved.
//  Originally created by Jonathon Horsman.
//
//  This code is released under the GNU Public License (GPL) version 2
//  For more information please refer to http://www.gnu.org/copyleft/gpl.html
//

#import "ViewController.h"
#import <AVFoundation/AVFoundation.h>

//#define LOGGING true // set to false to stop each received signal being logged
#define LOGGING false // set to false to stop each received signal being logged

#define AUDIO_FILE_NAME @"throttle_hover_ios.wav" // @"iOS_noflip.wav" //
#define POOR_SIGNAL_KEY @"poorSignal"
#define ATTENTION_KEY @"eSenseAttention"
#define MEDITATION_KEY @"eSenseMeditation"

@implementation ViewController {
   // these 2 arrays hold the values of the thrust which should be applied to the helicopter
   // (by way of volume level through the headphones) at each level of attention and meditation.
   // this could be calculated on the fly, but because it happens ~20 times per second, the
   // better option is to store all the values in arrays, and recalculate when the sliders are changed.
   float attentionPower[101];
   float meditationPower[101];
   
   int currentAttentionLevel, currentMeditationLevel; // the latest readings from the headset
   BOOL processingDevice;
   BOOL demoRunning;
}

@synthesize log, attention, meditation, signal, power, attentionThreshold, meditationThreshold, connectButton, demoButton;

- (void)viewDidLoad
{
   [super viewDidLoad];
   [self prepareAudio];
   [self.attentionThreshold addTarget:self action:@selector(calculatePowerValues) forControlEvents:UIControlEventValueChanged];
   [self.meditationThreshold addTarget:self action:@selector(calculatePowerValues) forControlEvents:UIControlEventValueChanged];
   [self calculatePowerValues];
   
}

- (void)didReceiveMemoryWarning
{
   [super didReceiveMemoryWarning];
   // Dispose of any resources that can be recreated.
   [self stopDemo];
}

// Start the data stream from the bluetooth headset if it's attached, and reset the display output
- (void) appForegrounded
{
   [self resetViews]; // just in case it didn't happen on close
}

// Set all levels back to zero and clear the log
- (void) resetViews
{
   [self resetOutputToZero];
   self.log.text = @"";
   [self printInstructions];
   
}

- (void) printInstructions
{
   [self logMessage:@"\nWelcome to Puzzlebox Orbit!\n\nInstructions for Use:\n1. Pair with EEG headset under Bluetooth Settings\n2. Attach infrared dongle to headphone port\n3. Raise volume to maximum level\n4. Press Connect button below to begin processing\n5. When Attention or Meditation levels cross the indicated threshold, the helicopter will take off\n\nPlease visit http://orbit.puzzlebox.info for more details"];
}

- (void) resetOutputToZero
{
   [self showSignalStrength:[NSNumber numberWithInt:200]];
   [self setAttentionLevel:[NSNumber numberWithInt:0]];
   [self setMeditationLevel:[NSNumber numberWithInt:0]];
   [self showPowerLevel];
}

- (void) appClosed
{
   [self stopDemo];
   [self resetViews];
   if ([[TGAccessoryManager sharedTGAccessoryManager] connected]) {
      [[TGAccessoryManager sharedTGAccessoryManager] stopStream];
   }
}

- (void) prepareAudio
{
   NSURL *audioFilePath = [[NSBundle mainBundle] URLForResource:AUDIO_FILE_NAME withExtension:nil];
   
   NSError *error;
   audioPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL:audioFilePath error:&error];
   if (!audioPlayer) {
      [self logMessage:[NSString stringWithFormat:@"Failed to initialize audio player: %@", [error debugDescription]]];
   } else {
      [audioPlayer prepareToPlay];
   }
}

- (void) logMessage:(NSString *) str
{
   log.text = [[NSString alloc] initWithFormat:@"%@\n%@", str, log.text];
}

- (void) logDataReceived:(NSDictionary *) data
{
   NSNumber *sig = [data valueForKey:POOR_SIGNAL_KEY];
   if (sig != NULL) {
      int val = (200 - [sig intValue]) / 2;
      [self logMessage:[NSString stringWithFormat:@"Signal strength: %u%%, Attention: %@%%, Meditation: %@%%",
                        val, [data valueForKey:ATTENTION_KEY], [data valueForKey:MEDITATION_KEY]]];
   }
   
}

#pragma mark - TGAccessoryDelegate methods

- (void)dataReceived:(NSDictionary *)data {
   [self performSelectorOnMainThread:@selector(updatedSignalReceived:)
                          withObject:data
                       waitUntilDone:NO];
}

- (void) updatedSignalReceived:(id) data
{
   if (LOGGING) {
      [self logDataReceived: data];
   }
   [self showSignalStrength:(NSNumber *)[data valueForKey:POOR_SIGNAL_KEY]];
   [self setAttentionLevel:(NSNumber *)[data valueForKey:ATTENTION_KEY]];
   [self setMeditationLevel:(NSNumber *)[data valueForKey:MEDITATION_KEY]];
   [self showPowerLevel];
   [self playAudio];
}

// The headset was switched on, start the data stream
- (void)accessoryDidConnect:(EAAccessory *)accessory {
   [self logMessage:[NSString stringWithFormat:@"%@ connected to this device", [accessory name]]];
   if ([[TGAccessoryManager sharedTGAccessoryManager] accessory] != nil) {
      [[TGAccessoryManager sharedTGAccessoryManager] startStream];
   }
}

// The headset was switched off (or the Bluetooth signal was dropped).
// Reset the outputs back to zero
- (void)accessoryDidDisconnect {
   [self logMessage:@"Accessory was disconnected"];
   [self resetOutputToZero];
}

#pragma mark - display calculation and update methods

// when the user adjusts one of the 2 threshold sliders we recalculate the power values at each of the 101 possible levels
- (void) calculatePowerValues
{
   float threshold = self.attentionThreshold.value; // this is the user-selected minimum threshold - between 0 and 1
   for (int i = 0; i < 101; i++) {
      attentionPower[i] = [self calculatePowerAt:(float)i/100 withThreshold:threshold];
   }
   threshold = self.meditationThreshold.value; // this is the user-selected minimum threshold - between 0 and 1
   for (int i = 0; i < 101; i++) {
      meditationPower[i] = [self calculatePowerAt:(float)i/100 withThreshold:threshold];
   }
}

// Convert a value (attention or meditation) into the corresponding power output (which is the volume level)
// given the threshold is set at specified value.
// The threshold is the value set by the user as the minimum value (attention or meditation) to be reached
// before the helicopter is given the signal to fly.
// If the value if below the threshold, the value will be zero (threshold not yet met).
// Otherwise the returned power value will be between 0 and 1.
- (float) calculatePowerAt:(float)value withThreshold:(float)threshold
{
   if (value < threshold) { // threshold not met
      return 0;
   }
   // e.g. if the threshold is 0.55 and the current value is 0.7:
   // there is 0.45 remaining of the threshold slider, and the value is 0.15 past the threshold (0.7 - 0.55), which is 0.33 (0.15 / 0.45)
   return (value - threshold) / (1 - threshold);
}

- (void) showSignalStrength:(NSNumber *) value
{
   if (value != nil) {
      self.signal.progress = (200.0 - [value intValue]) / 200.0;
   }
}

- (void) setAttentionLevel:(NSNumber *) value
{
   if (value != nil) {
      currentAttentionLevel = [value intValue];
      self.attention.progress = (float)currentAttentionLevel / 100;
   }
}

- (void) setMeditationLevel:(NSNumber *) value
{
   if (value != nil) {
      currentMeditationLevel = [value intValue];
      self.meditation.progress = (float)currentMeditationLevel / 100;
   }
}

// updates the power output progress bar
- (void) showPowerLevel
{
   self.power.progress = [self currentPowerLevel];
}

// calculate the total power level to output through the headphones, a value between zero and 1.
// this is the attention signal level and meditation signal level added together
- (float) currentPowerLevel
{
   float powerLevel = attentionPower[currentAttentionLevel] + meditationPower[currentMeditationLevel];
   if (powerLevel > 1) {
      return 1.0;
   }
   return powerLevel;
}

- (void) playAudio
{
   //   audioPlayer.volume = [self currentPowerLevel];
   if ([self currentPowerLevel] > 0) {
      audioPlayer.volume = 1.0;
      [audioPlayer play];
   } else {
      [audioPlayer stop];
   }
}

#pragma mark - button press events

// allow simulation of values being generated by a headset and being received on the phone
- (IBAction) demoButtonPressed:(id) sender
{
   if (demoRunning) {
      [self stopDemo];
   } else {
      [self startDemo];
   }
}

- (void) stopDemo
{
   demoRunning = NO;
   [self resetOutputToZero];
   [demoButton setTitle:@"Demo" forState:UIControlStateNormal];
   if (audioPlayer != NULL && [audioPlayer isPlaying]) {
      [audioPlayer stop];
   }
   [self logMessage:@"Demo stopped"];
}

- (void) startDemo
{
   demoRunning = YES;
   [self logMessage:@"Running demo"];
   [demoButton setTitle:@"Stop" forState:UIControlStateNormal];
   [self performSelectorInBackground:@selector(generateDemoData) withObject:nil];
}

// generate some data in a background thread and invoke the methods the headset would invoke with the data
// for testing without a headset.
- (void) generateDemoData
{
   while (demoRunning) {
      for (int i = 0; i < 100; i++) {
         if (!demoRunning) {
            break; // break out if we stop the demo
         }
         NSDictionary *values = [NSDictionary dictionaryWithObjectsAndKeys:
                                 [NSNumber numberWithInt:i], ATTENTION_KEY,
                                 [NSNumber numberWithInt:i * 0.8], MEDITATION_KEY,
                                 [NSNumber numberWithInt:0], POOR_SIGNAL_KEY,
                                 nil];
         [self dataReceived:values];
         [NSThread sleepForTimeInterval:0.1];
      }
      
      for (int i = 100; i > 0; i--) {
         if (!demoRunning) {
            break; // break out if we stop the demo
         }
         NSDictionary *values = [NSDictionary dictionaryWithObjectsAndKeys:
                                 [NSNumber numberWithInt:i], ATTENTION_KEY,
                                 [NSNumber numberWithInt:i * 0.8], MEDITATION_KEY,
                                 [NSNumber numberWithInt:0], POOR_SIGNAL_KEY,
                                 nil];
         [self dataReceived:values];
         [NSThread sleepForTimeInterval:0.1];
      }
      
   }
}

- (void) startProcessing
{
   processingDevice = YES;
   [self logMessage:@"Connecting to EEG Headset"];
   [connectButton setTitle:@"Disconnect" forState:UIControlStateNormal];
   
   EAAccessory *accessory = [[TGAccessoryManager sharedTGAccessoryManager] accessory];
   if (accessory != nil) {
      [self logMessage:[NSString stringWithFormat:@"EEG device %@ connected", accessory.name]];
      [[TGAccessoryManager sharedTGAccessoryManager] startStream];
   }
   
}

- (void) stopProcessing
{
   processingDevice = NO;
   [self logMessage:@"Disconnecting from EEG Headset"];
   if ([[TGAccessoryManager sharedTGAccessoryManager] connected]) {
      [[TGAccessoryManager sharedTGAccessoryManager] stopStream];
   }
   [connectButton setTitle:@"Connect" forState:UIControlStateNormal];
   
   [self resetOutputToZero];
   [audioPlayer stop];
   
}

- (IBAction) connectButtonPressed:(id) sender {
   
   if (processingDevice) {
      [self stopProcessing];
   } else {
      [self startProcessing];
   }
   
}
@end