Making a Voice Recorder on Windows Phone

using System;
using System.ComponentModel;
using System.Collections.Generic;
using System.Diagnostics;
using System.IO;
using System.Linq;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Shapes;
using System.Collections.ObjectModel;
using J2i.Net.VoiceRecorder.Utility;
using Microsoft.Phone.Shell;
using Microsoft.Xna.Framework.Audio;


namespace J2i.Net.VoiceRecorder.ViewModels
{
    public class MainViewModel : INotifyPropertyChanged
    {
        public MainViewModel()
        {
            this.Items = new ObservableCollection<RecordingDetails>();

            var isoStore = System.IO.IsolatedStorage.IsolatedStorageFile.GetUserStoreForApplication();

            if (!isoStore.DirectoryExists("settings"))
                isoStore.CreateDirectory("settings");
            if (!isoStore.DirectoryExists("data"))
                isoStore.CreateDirectory("data");
            if (!isoStore.DirectoryExists("recordings"))
                isoStore.CreateDirectory("recordings");

        }

        //public bool IsRecording { get; private set; }
        private Microphone _currentMicrophone;
        private MemoryStream _currentRecordingStream;
        private byte[] _audioBuffer;
        private bool _stopRequested;
        private int _sampleRate = 0;
        private string _baseFileName;

        private SoundEffectInstance _currentSound = null;
                
        // MyConfiguration - generated from ObservableField snippet - Joel Ivory Johnson
        private ConfigurationViewModel _myConfiguration;
        public ConfigurationViewModel MyConfiguration
        {
        get { return _myConfiguration ?? (_myConfiguration = ConfigurationViewModel.GetConfiguration()); }
            set
            {
                if (_myConfiguration != value)
                {
                    _myConfiguration = value;
                    NotifyPropertyChanged("MyConfiguration");
                }
            }
        }
        //-----


                
        // IsRecording - generated from ObservableField snippet - Joel Ivory Johnson

        private bool _isRecording;
        public bool IsRecording
        {
        get { return _isRecording; }
            set
            {
                if (_isRecording != value)
                {
                    _isRecording = value;
                    NotifyPropertyChanged("IsRecording");
                }
            }
        }
        //-----

        /// <summary>
        /// A collection for ItemViewModel objects.
        /// </summary>
        public ObservableCollection<RecordingDetails> Items { get; private set; }

        private RecordingDetails _selectedRecording;
        public RecordingDetails SelectedRecording
        {
            get { return _selectedRecording;  }
            set
            {
                if(value!=_selectedRecording)
                {
                    _selectedRecording = value;
                    NotifyPropertyChanged("SelectedRecording");
                    if (value != null)
                        LastSelectedRecording = value;
                }
            }
        }

                
        // LastSelectedRecording - generated from ObservableField snippet - Joel Ivory Johnson

        private RecordingDetails _lastSelectedRecording;
        public RecordingDetails LastSelectedRecording
        {
        get { return _lastSelectedRecording; }
            set
            {
                if (_lastSelectedRecording != value)
                {
                    _lastSelectedRecording = value;
                    NotifyPropertyChanged("LastSelectedRecording");
                }
            }
        }
        //-----


        public void ApplySettings()
        {
            PhoneApplicationService.Current.ApplicationIdleDetectionMode = (MyConfiguration.AllowRunUnderLockScreen)
                                                                               ? IdleDetectionMode.Disabled
                                                                               : IdleDetectionMode.Enabled;
        }

        public void CreateNewRecording()
        {
            SelectedRecording = new RecordingDetails() {Title = DateTime.Now.ToLongDateString(), IsNew = true};
        }

        public void StartRecording()
        {
            if (_currentMicrophone == null)
            {
                _currentMicrophone = Microphone.Default;
                _currentMicrophone.BufferReady += new EventHandler<EventArgs>(_currentMicrophone_BufferReady);
                _audioBuffer = new byte[_currentMicrophone.GetSampleSizeInBytes(_currentMicrophone.BufferDuration)];
                _sampleRate = _currentMicrophone.SampleRate;
            }

            //SelectedRecording = new RecordingDetails(){Title = DateTime.Now.ToString(), TimeStamp = DateTime.Now};
            _baseFileName = (DateTime.Now.Ticks/10000).ToString();            
            _stopRequested = false;
            _currentRecordingStream = new MemoryStream(1048576);
            IsRecording = true;
            _currentMicrophone.Start();
        }


        public void RequestStopRecording()
        {
            _stopRequested = true;
        }

        void _currentMicrophone_BufferReady(object sender, EventArgs e)
        {
            _currentMicrophone.GetData(_audioBuffer);
            _currentRecordingStream.Write(_audioBuffer,0,_audioBuffer.Length);
            if (!_stopRequested) return;
            _currentMicrophone.Stop();
            var isoStore = System.IO.IsolatedStorage.IsolatedStorageFile.GetUserStoreForApplication();

            using (var targetFile = isoStore.CreateFile(SelectedRecording.FilePath = String.Format("recordings/{0}.wav", _baseFileName)))
            {
                WaveHeaderWriter.WriteHeader(targetFile, (int)_currentRecordingStream.Length, 1, _sampleRate);
                var dataBuffer = _currentRecordingStream.GetBuffer();
                targetFile.Write(dataBuffer,0,(int)_currentRecordingStream.Length);                    
                targetFile.Flush();
                targetFile.Close();
            }
            IsRecording = false;
            CommitRecording();
            LoadData();
        }

        public void CommitRecording()
        {                
            var myDataSaver = new DataSaver<RecordingDetails>() {};
            myDataSaver.SaveMyData(LastSelectedRecording,String.Format("data/{0}.dat",_baseFileName) );
            
        }

        public void SaveUpdate()
        {
            var myDataSaver = new DataSaver<RecordingDetails>() {};
            myDataSaver.SaveMyData(LastSelectedRecording, LastSelectedRecording.SourceFileName);
        }

        public void ReloadUpdate()
        {
            var myDataSaver = new DataSaver<RecordingDetails>();
            var item = myDataSaver.LoadMyData(LastSelectedRecording.SourceFileName);
            item.SourceFileName = LastSelectedRecording.SourceFileName;
            LastSelectedRecording.Copy(item);
        }

        public void Delete(RecordingDetails target)
        {
            var isoStore = System.IO.IsolatedStorage.IsolatedStorageFile.GetUserStoreForApplication();

            //delete the wave file
            isoStore.DeleteFile(target.FilePath);
            //delete the file description
            isoStore.DeleteFile(target.SourceFileName);

            this.LoadData();
            
        }

        public void PlayRecording(RecordingDetails source)
        {
            SoundEffect se;
            if(_currentSound!=null)
            {
                _currentSound.Stop();
                _currentSound = null;
            }
            var isoStore = System.IO.IsolatedStorage.IsolatedStorageFile.GetUserStoreForApplication();
            if(isoStore.FileExists(source.FilePath))
            {
                byte[] fileContents;
                using (var fileStream = isoStore.OpenFile(source.FilePath, FileMode.Open))
                {
                    se = SoundEffect.FromStream(fileStream);
                    fileStream.Close();//not really needed, but it makes me feel better. 
                }

                _currentSound = se.CreateInstance();
                _currentSound.Play();
            }
        }



        private string _sampleProperty = "Sample Runtime Property Value";
        /// <summary>
        /// Sample ViewModel property; this property is used in the view to display its value using a Binding
        /// </summary>
        /// <returns></returns>
        public string SampleProperty
        {
            get
            {
                return _sampleProperty;
            }
            set
            {
                if (value != _sampleProperty)
                {
                    _sampleProperty = value;
                    NotifyPropertyChanged("SampleProperty");
                }
            }
        }

        public bool IsDataLoaded
        {
            get;
            private set;
        }

        /// <summary>
        /// Creates and adds a few ItemViewModel objects into the Items collection.
        /// </summary>
public void LoadData()
{
    var isoStore = System.IO.IsolatedStorage.IsolatedStorageFile.GetUserStoreForApplication();
    var recordingList = isoStore.GetFileNames("data/*.xml");
    var myDataSaver = new DataSaver<RecordingDetails>();
    Items.Clear();
    foreach (var desc in recordingList.Select(item =>
                                                    {
                                                        var result =myDataSaver.LoadMyData(String.Format("data/{0}", item));
                                                        result.SourceFileName = String.Format("data/{0}", item);
                                                        return result;
                                                    }))
    {
        Items.Add(desc);
    }
    this.IsDataLoaded = true;
}

        public event PropertyChangedEventHandler PropertyChanged;
        private void NotifyPropertyChanged(String propertyName)
        {
            PropertyChangedEventHandler handler = PropertyChanged;
            if (null != handler)
            {
                handler(this, new PropertyChangedEventArgs(propertyName));
            }
        }
    }
}