PasswordResetDialog.vb

Imports System.Windows.Forms
Imports System.Drawing

''' <summary>
''' Small modal dialog that asks an administrator for a new password, entered
''' twice and masked. Use the shared <see cref="Prompt"/> helper; it returns the
''' validated new password, or Nothing if the admin cancels.
''' Built entirely in code so it needs no Designer/.resx file.
''' </summary>
Public Class PasswordResetDialog
    Inherits Form

    Private Const MinPasswordLength As Integer = 4

    Private ReadOnly txtNew As New TextBox()
    Private ReadOnly txtConfirm As New TextBox()
    Private ReadOnly lblError As New Label()

    Public Property NewPassword As String = Nothing

    Private Sub New(targetUser As String)
        Me.Text = "Reset Password"
        Me.FormBorderStyle = FormBorderStyle.FixedDialog
        Me.StartPosition = FormStartPosition.CenterParent
        Me.MaximizeBox = False
        Me.MinimizeBox = False
        Me.ShowInTaskbar = False
        Me.ClientSize = New Size(380, 226)

        Dim lblInfo As New Label() With {
            .Text = "Set a new password for: " & targetUser,
            .Location = New Point(16, 14), .Size = New Size(348, 22),
            .Font = New Font("Segoe UI", 9.0!, FontStyle.Bold)
        }

        Dim lblNew As New Label() With {.Text = "New password", .Location = New Point(16, 46), .Size = New Size(160, 20)}
        txtNew.Location = New Point(16, 68) : txtNew.Size = New Size(348, 26)
        txtNew.UseSystemPasswordChar = True

        Dim lblConfirm As New Label() With {.Text = "Confirm password", .Location = New Point(16, 100), .Size = New Size(160, 20)}
        txtConfirm.Location = New Point(16, 122) : txtConfirm.Size = New Size(348, 26)
        txtConfirm.UseSystemPasswordChar = True

        lblError.Location = New Point(16, 154) : lblError.Size = New Size(348, 20)
        lblError.ForeColor = Color.Firebrick

        Dim btnOk As New Button() With {.Text = "Reset", .Location = New Point(196, 184), .Size = New Size(80, 30)}
        Dim btnCancel As New Button() With {.Text = "Cancel", .Location = New Point(284, 184), .Size = New Size(80, 30), .DialogResult = DialogResult.Cancel}
        AddHandler btnOk.Click, AddressOf OnOk

        Me.Controls.AddRange(New Control() {lblInfo, lblNew, txtNew, lblConfirm, txtConfirm, lblError, btnOk, btnCancel})
        Me.AcceptButton = btnOk
        Me.CancelButton = btnCancel

        UiHelper.Polish(Me)
    End Sub

    Private Sub OnOk(sender As Object, e As EventArgs)
        Dim pwd As String = txtNew.Text
        If String.IsNullOrWhiteSpace(pwd) Then
            lblError.Text = "Password is required."
            Return
        End If
        If pwd.Length < MinPasswordLength Then
            lblError.Text = $"Password must be at least {MinPasswordLength} characters."
            Return
        End If
        If pwd <> txtConfirm.Text Then
            lblError.Text = "Passwords do not match."
            Return
        End If

        NewPassword = pwd
        Me.DialogResult = DialogResult.OK
        Me.Close()
    End Sub

    ''' <summary>Show the dialog; returns the new password, or Nothing if cancelled.</summary>
    Public Shared Function Prompt(owner As IWin32Window, targetUser As String) As String
        Using dlg As New PasswordResetDialog(targetUser)
            If dlg.ShowDialog(owner) = DialogResult.OK Then
                Return dlg.NewPassword
            End If
            Return Nothing
        End Using
    End Function

End Class