microsoft-visualbasic-runtime/CommandLine/InteropService/CLIAbstractor.vb

#Region "Microsoft.VisualBasic::620a74df1490b707ca723085e2996b2e, Microsoft.VisualBasic.Core\CommandLine\InteropService\CLIAbstractor.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:

    '     Module CLIAbstractor
    ' 
    '         Function: CLICaller, CLIUsage
    ' 
    ' 
    ' /********************************************************************************/

#End Region

Imports System.Reflection
Imports System.Runtime.CompilerServices
Imports System.Text
Imports Microsoft.VisualBasic.Language
Imports Microsoft.VisualBasic.Scripting.Runtime

Namespace CommandLine.InteropService

    ''' <summary>
    ''' 将函数的定义抽象为一个命令行，从而能够提供更好的命令行编写服务
    ''' </summary>
    Public Module CLIAbstractor

        ''' <summary>
        ''' Abstract the function declare as a CLI usage declare. This tool not support the generic function method.
        ''' (不支持泛型函数)
        ''' </summary>
        ''' <param name="api"></param>
        ''' <param name="prefix$"></param>
        ''' <returns></returns>
        Public Function CLIUsage(api As MethodInfo, Optional prefix$ = "/") As String
            Dim isGeneric = (Not api.GetGenericArguments.IsNullOrEmpty) Or die($"Function abstract tool not working on a generic method: {api.DeclaringType.FullName}::{api.Name}!")
            Dim name$ = prefix & api.Name
            Dim args As New List(Of ParameterInfo)(api.GetParameters)
            Dim optionalArguments = args.Where(Function(param) param.IsOptional).ToArray
            Dim requiredArguments = args - optionalArguments
            Dim usage As New StringBuilder
            Dim required$ = requiredArguments _
                .Select(Function(param)
                            Return $"{prefix}{param.Name} <value:={param.Name}>"
                        End Function) _
                .JoinBy(" ")
            Dim optionals = optionalArguments _
                .Select(Function(param)
                            If param.ParameterType Is GetType(Boolean) Then
                                Return $"{prefix}{param.Name}"
                            Else
                                Dim default$ = $"<default={CStrSafe(param.DefaultValue)}>"
                                Return $"{prefix}{param.Name} {[default]}"
                            End If
                        End Function) _
                .JoinBy(" ")

            Call usage.Append(name & " ")
            Call usage.Append(required)
            Call usage.Append(" ")
            Call usage.Append($"[{optionals}]")

            Return usage.ToString.Trim
        End Function

        <Extension> Public Function CLICaller(api As MethodInfo, args As CommandLine) As Integer
            Dim paramValues As List(Of Object)
            Dim names As Dictionary(Of String, String)
            Dim parameters = api.GetParameters

            If parameters.Length = 1 AndAlso parameters(Scan0).ParameterType Is GetType(CommandLine) Then
                Return DirectCast(api.Invoke(Nothing, {args}), Integer)
            Else
                paramValues = New List(Of Object)
            End If

            names = args _
                .Keys _
                .ToDictionary(Function(k)
                                  Return k.Trim("/"c, "-"c).Trim.ToLower
                              End Function)

            For Each param As ParameterInfo In api.GetParameters
                Dim name$ = param.Name.ToLower

                If param.ParameterType Is GetType(Boolean) Then
                    paramValues += names.ContainsKey(name)
                Else
                    paramValues += Scripting.CTypeDynamic(
                        args(names(name)),
                        param.ParameterType
                    )
                End If
            Next

            Dim result% = DirectCast(api.Invoke(Nothing, paramValues.ToArray), Integer)
            Return result
        End Function
    End Module
End Namespace