microsoft-visualbasic-runtime/CommandLine/Interpreters/InteractiveConsole.vb

#Region "Microsoft.VisualBasic::09098ae865331d9e19fb5d120aa4c694, Microsoft.VisualBasic.Core\CommandLine\Interpreters\InteractiveConsole.vb"

    ' Author:
    ' 
    '       asuka (amethyst.asuka@gcmodeller.org)
    '       xie (genetics@smrucc.org)
    '       xieguigang (xie.guigang@live.com)
    ' 
    ' Copyright (c) 2018 GPL3 Licensed
    ' 
    ' 
    ' GNU GENERAL PUBLIC LICENSE (GPL3)
    ' 
    ' 
    ' This program is free software: you can redistribute it and/or modify
    ' it under the terms of the GNU General Public License as published by
    ' the Free Software Foundation, either version 3 of the License, or
    ' (at your option) any later version.
    ' 
    ' This program is distributed in the hope that it will be useful,
    ' but WITHOUT ANY WARRANTY; without even the implied warranty of
    ' MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    ' GNU General Public License for more details.
    ' 
    ' You should have received a copy of the GNU General Public License
    ' along with this program. If not, see <http://www.gnu.org/licenses/>.



    ' /********************************************************************************/

    ' Summaries:

    '     Class InteractiveConsole
    ' 
    '         Constructor: (+1 Overloads) Sub New
    ' 
    '         Function: RunApp
    ' 
    '         Sub: doListingDirectory, RunAppInternal
    ' 
    ' 
    ' /********************************************************************************/

#End Region

Imports System.IO
Imports Microsoft.VisualBasic.ApplicationServices.Terminal
Imports Microsoft.VisualBasic.Language.UnixBash
Imports Microsoft.VisualBasic.Linq
Imports Microsoft.VisualBasic.Scripting.Expressions

Namespace CommandLine

    ''' <summary>
    ''' interactive console in ``/i`` mode, example:
    ''' 
    ''' ```bash
    ''' # This command will makes your CLI program enter 
    ''' # the interactive console mode.
    ''' # 
    ''' # type quit() for exit.
    ''' #
    ''' App /i
    ''' ```
    ''' </summary>
    ''' <remarks></remarks>
    Public NotInheritable Class InteractiveConsole : Inherits Interpreter

        Sub New(App As Type)
            Call MyBase.New(App)
        End Sub

        Public Function RunApp() As Integer
            Dim shell As New Shell(
                ps1:=PS1.Fedora12,
                exec:=Sub(input)
                          Call CLITools.TryParse(input).DoCall(AddressOf RunAppInternal)
                      End Sub
            ) With {
                .Quite = "exit"
            }

            Call MyBase.Execute(args:=New CommandLine With {.Name = "?"})

            Call Console.WriteLine()
            Call Console.WriteLine()
            Call Console.Write(shell.ps1.ToString)
            Call Console.Write(" ")

            ' 代码执行会被阻塞在这里, 直到输入exit退出
            Call shell.Run()
            Call Console.WriteLine("Bye bye.")

            Return 0
        End Function

        Private Sub doListingDirectory(cmd As CommandLine)
            Dim directory$ = If(cmd.Tokens.ElementAtOrDefault(1), App.CurrentDirectory)

            If Not directory.DirectoryExists Then
                Console.ForegroundColor = ConsoleColor.Red
                Console.WriteLine($"Directory ""{directory}"" not exist on your filesystem!")
                Console.ForegroundColor = ConsoleColor.White

                Return
            End If

            Dim directories = FileIO.FileSystem.GetDirectories(directory)
            Dim files = FileIO.FileSystem.GetFiles(directory)

            For Each dir As String In directories
                Call Console.WriteLine("<directory> " & dir.Replace("\"c, "/"c).Split("/"c).Last)
            Next

            Dim table = files _
                .Select(Function(path)
                            Return {
                                path.Replace("\"c, "/"c).Split("/"c).Last,
                                New FileInfo(path).Length & " Bytes"
                            }
                        End Function) _
                .ToArray

            Call PrintAsTable.Print(table, New StreamWriter(Console.OpenStandardOutput))
        End Sub

        ''' <summary>
        ''' Contains sevral build in command about file system operation and the program CLI interpreter commands
        ''' </summary>
        ''' <param name="cmd"></param>
        Private Sub RunAppInternal(cmd As CommandLine)
            Select Case cmd.Name.ToLower

                Case "ls"   ' list directory

                    Call doListingDirectory(cmd)

                Case "cd"   ' change directory

                    App.CurrentDirectory = cmd.Tokens.ElementAtOrDefault(1)

                Case "cat"  ' display text file content

                    Call Console.WriteLine(cmd.Tokens.ElementAtOrDefault(1).ReadAllText)

                Case "help" ' view commandline help 

                    Call MyBase.Execute(args:=New CommandLine With {.Name = "?"})
                    Call Console.WriteLine()
                    Call Console.WriteLine()

                Case "pwd"
                    Call Console.WriteLine(App.CurrentDirectory)

                Case "/@set"

                    ' /@set var value
                    Dim var$ = cmd.Tokens.ElementAtOrDefault(1)
                    Dim value$ = cmd _
                        .Tokens _
                        .ElementAtOrDefault(2) _
                        .Interpolate(AddressOf App.GetVariable, escape:=False)

                    Call App.JoinVariable(var, value)

                Case "/@get"

                    ' /@get var
                    Call Console.WriteLine(App.GetVariable(cmd.Tokens.ElementAtOrDefault(1)))

                Case Else

                    Call MyBase.Execute(args:=cmd)

            End Select
        End Sub
    End Class
End Namespace