Option Explicit On 
Option Strict On

Public Class Person

    Public Sub New( _
        ByVal firstName As String, _
        ByVal lastName As String)

        Me.SetFirstName(firstName)
        Me.SetLastName(lastName)
        Me.SetCountryOfBirth(DEFAULT_COUNTRY_OF_BIRTH)

    End Sub

    Public Sub New( _
        ByVal firstName As String, _
        ByVal middleName As String, _
        ByVal lastName As String, _
        ByVal countryOfBirth As String)

        Me.SetFirstName(firstName)
        Me.SetMiddleName(middleName)
        Me.SetLastName(lastName)
        Me.SetCountryOfBirth(countryOfBirth)

    End Sub

    '
    ' FirstName
    '

    Private m_firstName As String = Nothing

    Public Function GetFirstName() As String
        If m_firstName Is Nothing Then
            Throw New Exception("firstName not set")
        End If
        Return m_firstName
    End Function

    Public Sub SetFirstName(ByVal firstName As String)
        If firstName Is Nothing Then
            Throw New ArgumentNullException( _
                "firstName cannot be null")
        End If
        If firstName = "" Then
            Throw New ArgumentException( _
                "firstName cannot be blank")
        End If
        m_firstName = firstName
    End Sub

    '
    ' MiddleName
    '

    Private m_middleName As String = Nothing

    Public Function GetMiddleName() As String
        If m_middleName Is Nothing Then
            Throw New Exception("middleName not set")
        End If
        Return m_middleName
    End Function

    Public Sub SetMiddleName(ByVal middleName As String)
        If middleName Is Nothing Then
            Throw New ArgumentNullException( _
                "middleName cannot be null")
        End If
        If middleName = "" Then
            Throw New ArgumentException( _
                "middleName cannot be blank")
        End If
        m_middleName = middleName
    End Sub

    Public Sub ClearMiddleName()
        m_middleName = Nothing
    End Sub

    Public Function HasMiddleName() As Boolean
        Return Not m_middleName Is Nothing
    End Function

    '
    ' LastName
    '

    Private m_lastName As String = Nothing

    Public Function GetLastName() As String
        If m_lastName Is Nothing Then
            Throw New Exception("lastName not set")
        End If
        Return m_lastName
    End Function

    Public Sub SetLastName(ByVal lastName As String)
        If lastName Is Nothing Then
            Throw New ArgumentNullException( _
                "lastName cannot be null")
        End If
        If lastName = "" Then
            Throw New ArgumentException( _
                "lastName cannot be blank")
        End If
        m_lastName = lastName
    End Sub

    '
    ' CountryOfBirth
    '

    Private Shared ReadOnly DEFAULT_COUNTRY_OF_BIRTH As String = "Thailand"

    Private m_countryOfBirth As String = Nothing

    Public Function GetCountryOfBirth() As String
        If m_countryOfBirth Is Nothing Then
            Throw New Exception("countryOfBirth not set")
        End If
        Return m_countryOfBirth
    End Function

    Public Sub SetCountryOfBirth(ByVal countryOfBirth As String)
        If countryOfBirth Is Nothing Then
            Throw New ArgumentNullException( _
                "countryOfBirth cannot be null")
        End If
        If countryOfBirth = "" Then
            Throw New ArgumentException( _
                "countryOfBirth cannot be blank")
        End If
        m_countryOfBirth = countryOfBirth
    End Sub


End Class