/Source Code/SongDatabase/Items/SongItem.vb

Imports System.IO



Namespace Items



    ''' <summary>

    ''' Represents a type of item that is a song.

    ''' </summary>

    Public Class SongItem

        Inherits BaseItem



        Private FSongID As Guid = Nothing



        ''' <summary>

        ''' Gets or sets the song ID.

        ''' </summary>

        ''' <value>The unique ID of the song.</value>

        Public Property SongID() As Guid

            Get

                If FSongID = Nothing Then Throw New ApplicationException("No ID has been set for this song.")

                Return FSongID

            End Get

            Set(ByVal value As Guid)

                If FSongID <> Nothing Then Throw New ApplicationException("An ID has already been set for this song.")

                FSongID = value

            End Set

        End Property



        ''' <summary>

        ''' Gets or sets the authors of the song.

        ''' </summary>

        ''' <value>The song's authors.</value>

        Public Property Authors() As List(Of String) = New List(Of String)



        Private FCategories As New List(Of Guid)



        ''' <summary>

        ''' Gets the categories the song is assigned to.

        ''' </summary>

        ''' <value>The list of categories the song is assigned to.</value>

        Public ReadOnly Property Categories() As List(Of Guid)

            Get

                Return FCategories

            End Get

        End Property



        ''' <summary>

        ''' Initializes a new instance of the <see cref="SongItem" /> class.

        ''' </summary>

        Public Sub New()



        End Sub



        ''' <summary>

        ''' Initializes a new instance of the <see cref="SongItem" /> class.

        ''' </summary>

        ''' <param name="title">The title of the song.</param>

        ''' <param name="parts">The parts / verses that make up the song.</param>

        Public Sub New(ByVal title As String, ByVal ParamArray parts() As String)

            MyBase.Title = title

            For Each Part As String In parts

                Me.Parts.Add(Part)

            Next

        End Sub



        ''' <summary>

        ''' Loads the song from the specified file name.

        ''' </summary>

        ''' <param name="fileName">Name of the file to load.</param>

        ''' <returns>A song item, whose contents are defined in the specified file.</returns>

        Public Shared Function Load(ByVal fileName As String) As SongItem



            ' Open the file

            Dim File As New BinaryReader(New FileStream(fileName, FileMode.Open))



            ' Get the ID of the song

            Dim Result As New SongItem

            Result.SongID = New Guid(IO.Path.GetFileNameWithoutExtension(fileName))



            ' Keep reading the file

            While File.BaseStream.Position < File.BaseStream.Length



                ' Read the name of the next datum

                Select Case File.ReadString



                    Case "TITLE"

                        Result.Title = File.ReadString



                    Case "AUTHOR"

                        Result.Authors.Add(File.ReadString)



                    Case "COPYRIGHTLINE"

                        Result.CopyrightLine = File.ReadString



                    Case "PART"

                        Result.Parts.Add(File.ReadString)



                End Select

            End While



            ' Return the song

            File.Close()

            Return Result



        End Function



        ''' <summary>

        ''' Saves the song to the specified file name.

        ''' </summary>

        ''' <param name="fileName">Name of the file to write the song to.</param>

        Public Sub Save(ByVal fileName As String)



            ' Create a new file

            Dim File As New BinaryWriter(New FileStream(fileName, FileMode.Create))



            ' Write title

            File.Write("TITLE")

            File.Write(MyBase.Title)



            ' Write list of authors

            For Each Author As String In Me.Authors

                File.Write("AUTHOR")

                File.Write(Author)

            Next



            ' Write parts

            For Each Part As String In MyBase.Parts

                File.Write("PART")

                File.Write(Part)

            Next



            ' Write copyright details

            File.Write("COPYRIGHTLINE")

            File.Write(MyBase.CopyrightLine)



            ' Close the file

            File.Close()



        End Sub



    End Class



End Namespace