using namespace System.Diagnostics

# Minishell (Singleshell) is a powershell concept.
# Its primary use-case is when somebody executes a scriptblock in the new powershell process.
# The objects are automatically marshelled to the child process and 
# back to the parent session, so users can avoid custom
# serialization to pass objects between two processes.

Describe 'minishell for native executables' -Tag 'CI' {
    
    BeforeAll {
        $powershell = Join-Path -Path $PsHome -ChildPath "powershell"
    }

    Context 'Streams from minishell' {

        It 'gets a hashtable object from minishell' {
            $output = & $powershell -noprofile { @{'a' = 'b'} }
            ($output | measure).Count | Should Be 1
            ($output.GetType().Name) | Should Be 'Hashtable'
            $output['a'] | Should Be 'b'
        }

        It 'gets the error stream from minishell' {
            $output = & $powershell -noprofile { Write-Error 'foo' } 2>&1
            ($output | measure).Count | Should Be 1
            ($output.GetType().Name) | Should Be 'ErrorRecord'
            $output.FullyQualifiedErrorId | Should Be 'Microsoft.PowerShell.Commands.WriteErrorException'
        }

        It 'gets the information stream from minishell' {
            $output = & $powershell -noprofile { Write-Information 'foo' } 6>&1
            ($output.GetType().Name) | Should Be 'InformationRecord'
            $output | Should Be 'foo'
        }
    }

    Context 'Streams to minishell' {
        It "passes input into minishell" {
            $a = 1,2,3
            $val  = $a | & $powershell -noprofile -command { $input }
            $val.Count | Should Be 3
            $val[0] | Should Be 1
            $val[1] | Should Be 2
            $val[2] | Should Be 3
        }
    }
}

Describe "ConsoleHost unit tests" -tags "Feature" {

    BeforeAll {
        $powershell = Join-Path -Path $PsHome -ChildPath "powershell"

        function NewProcessStartInfo([string]$CommandLine, [switch]$RedirectStdIn)
        {
            return [ProcessStartInfo]@{
                FileName               = $powershell
                Arguments              = $CommandLine
                RedirectStandardInput  = $RedirectStdIn
                RedirectStandardOutput = $true
                RedirectStandardError  = $true
                UseShellExecute        = $false
            }
        }

        function RunPowerShell([ProcessStartInfo]$si)
        {
            $process = [Process]::Start($si)

            return $process
        }

        function EnsureChildHasExited([Process]$process, [int]$WaitTimeInMS = 15000)
        {
            $process.WaitForExit($WaitTimeInMS)

            if (!$process.HasExited)
            {
                $process.HasExited | Should Be $true
                $process.Kill()
            }
        }
    }
    
    AfterEach {
        $Error.Clear()
    }

    Context "ShellInterop" {
        It "Verify Parsing Error Output Format Single Shell should throw exception" {
            try 
            {
                & $powershell -outp blah -comm { $input }
                Throw "Test execution should not reach here!"
            }
            catch
            {
                $_.FullyQualifiedErrorId | Should Be "IncorrectValueForFormatParameter"
            }
        }
        
        It "Verify Validate Dollar Error Populated should throw exception" {
            $origEA = $ErrorActionPreference
            $ErrorActionPreference = "Stop"
            try
            {
                $a = 1,2,3
                $a | & $powershell -noprofile -command { wgwg-wrwrhqwrhrh35h3h3}
                Throw "Test execution should not reach here!"
            }
            catch
            {
                $_.ToString() | Should Match "wgwg-wrwrhqwrhrh35h3h3"
                $_.FullyQualifiedErrorId | Should Be "CommandNotFoundException"
            }
            finally
            {
                $ErrorActionPreference = $origEA
            }
        }
        
        It "Verify Validate Output Format As Text Explicitly Child Single Shell should works" {
            {
                $a="blahblah"
                $a | & $powershell -noprofile -out text -com { $input }
            } | Should Not Throw
        }
        
        It "Verify Parsing Error Input Format Single Shell should throw exception" {
            try 
            {
                & $powershell -input blah -comm { $input }
                Throw "Test execution should not reach here!"
            }
            catch
            {
                $_.FullyQualifiedErrorId | Should Be "IncorrectValueForFormatParameter"
            }
        }
    }
    Context "CommandLine" {
        It "simple -args" {
            & $powershell -noprofile { $args[0] } -args "hello world" | Should Be "hello world"
        }

        It "array -args" {
            & $powershell -noprofile { $args[0] } -args 1,(2,3) | Should Be 1
            (& $powershell -noprofile { $args[1] } -args 1,(2,3))[1]  | Should Be 3
        }
        foreach ($x in "--help", "-help", "-h", "-?", "--he", "-hel", "--HELP", "-hEl") {
            It "Accepts '$x' as a parameter for help" {
                & $powershell -noprofile $x | ?{ $_ -match "PowerShell[.exe] -Help | -? | /?" } | Should Not BeNullOrEmpty
            }
        }

        It "Should accept a Base64 encoded command" {
            $commandString = "Get-Location"
            $encodedCommand = [System.Convert]::ToBase64String([System.Text.Encoding]::Unicode.GetBytes($commandString))
            # We don't compare to `Get-Location` directly because object and formatted output comparisons are difficult
            $expected = & $powershell -noprofile -command $commandString
            $actual = & $powershell -noprofile -EncodedCommand $encodedCommand
            $actual | Should Be $expected
        }

    }

    Context "Pipe to/from powershell" {
        $p = [PSCustomObject]@{X=10;Y=20}

        It "xml input" {
            $p | & $powershell -noprofile { $input | Foreach-Object {$a = 0} { $a += $_.X + $_.Y } { $a } } | Should Be 30
            $p | & $powershell -noprofile -inputFormat xml { $input | Foreach-Object {$a = 0} { $a += $_.X + $_.Y } { $a } } | Should Be 30
        }

        It "text input" {
            # Join (multiple lines) and remove whitespace (we don't care about spacing) to verify we converted to string (by generating a table)
            $p | & $powershell -noprofile -inputFormat text { -join ($input -replace "\s","") } | Should Be "XY--1020"
        }

        It "xml output" {
            & $powershell -noprofile { [PSCustomObject]@{X=10;Y=20} } | Foreach-Object {$a = 0} { $a += $_.X + $_.Y } { $a } | Should Be 30
            & $powershell -noprofile -outputFormat xml { [PSCustomObject]@{X=10;Y=20} } | Foreach-Object {$a = 0} { $a += $_.X + $_.Y } { $a } | Should Be 30
        }

        It "text output" {
            # Join (multiple lines) and remove whitespace (we don't care about spacing) to verify we converted to string (by generating a table)
            -join (& $powershell -noprofile -outputFormat text { [PSCustomObject]@{X=10;Y=20} }) -replace "\s","" | Should Be "XY--1020"
        }
    }

    Context "Redirected standard output" {
        It "Simple redirected output" {
            $si = NewProcessStartInfo "-noprofile 1+1"
            $process = RunPowerShell $si
            $process.StandardOutput.ReadToEnd() | Should Be 2
            EnsureChildHasExited $process
        }
    }

    Context "Input redirected but not reading from stdin (not really interactive)" {
        # Tests under this context are testing that we do not read from StandardInput
        # even though it is redirected - we want to make sure we don't hang.
        # So none of these tests should close StandardInput

        It "Redirected input w/ implicit -Command w/ -NonInteractive" {
            $si = NewProcessStartInfo "-NonInteractive -noprofile 1+1" -RedirectStdIn
            $process = RunPowerShell $si
            $process.StandardOutput.ReadToEnd() | Should Be 2
            EnsureChildHasExited $process
        }

        It "Redirected input w/ implicit -Command w/o -NonInteractive" {
            $si = NewProcessStartInfo "-noprofile 1+1" -RedirectStdIn
            $process = RunPowerShell $si
            $process.StandardOutput.ReadToEnd() | Should Be 2
            EnsureChildHasExited $process
        }

        It "Redirected input w/ explicit -Command w/ -NonInteractive" {
            $si = NewProcessStartInfo "-NonInteractive -noprofile -Command 1+1" -RedirectStdIn
            $process = RunPowerShell $si
            $process.StandardOutput.ReadToEnd() | Should Be 2
            EnsureChildHasExited $process
        }

        It "Redirected input w/ explicit -Command w/o -NonInteractive" {
            $si = NewProcessStartInfo "-noprofile -Command 1+1" -RedirectStdIn
            $process = RunPowerShell $si
            $process.StandardOutput.ReadToEnd() | Should Be 2
            EnsureChildHasExited $process
        }

        It "Redirected input w/ -File w/ -NonInteractive" {
            '1+1' | Out-File -Encoding Ascii -FilePath TestDrive:test.ps1 -Force
            $si = NewProcessStartInfo "-noprofile -NonInteractive -File $testDrive\test.ps1" -RedirectStdIn
            $process = RunPowerShell $si
            $process.StandardOutput.ReadToEnd() | Should Be 2
            EnsureChildHasExited $process
        }

        It "Redirected input w/ -File w/o -NonInteractive" {
            '1+1' | Out-File -Encoding Ascii -FilePath TestDrive:test.ps1 -Force
            $si = NewProcessStartInfo "-noprofile -File $testDrive\test.ps1" -RedirectStdIn
            $process = RunPowerShell $si
            $process.StandardOutput.ReadToEnd() | Should Be 2
            EnsureChildHasExited $process
        }
    }

    Context "Redirected standard input for 'interactive' use" {
        $nl = [Environment]::Newline

        # All of the following tests replace the prompt (either via an initial command or interactively)
        # so that we can read StandardOutput and reliably know exactly what the prompt is.

        It "Interactive redirected input" {
            $si = NewProcessStartInfo "-noprofile -nologo" -RedirectStdIn
            $process = RunPowerShell $si
            $process.StandardInput.Write("`$function:prompt = { 'PS> ' }`n")
            $null = $process.StandardOutput.ReadLine()
            $process.StandardInput.Write("1+1`n")
            $process.StandardOutput.ReadLine() | Should Be "PS> 1+1"
            $process.StandardOutput.ReadLine() | Should Be "2"
            $process.StandardInput.Write("1+2`n")
            $process.StandardOutput.ReadLine() | Should Be "PS> 1+2"
            $process.StandardOutput.ReadLine() | Should Be "3"

            # Backspace should work as expected
            $process.StandardInput.Write("1+2`b3`n")
            # A real console should render 2`b3 as just 3, but we're just capturing exactly what is written
            $process.StandardOutput.ReadLine() | Should Be "PS> 1+2`b3"
            $process.StandardOutput.ReadLine() | Should Be "4"
            $process.StandardInput.Close()
            $process.StandardOutput.ReadToEnd() | Should Be "PS> "
            EnsureChildHasExited $process
        }

        It "Interactive redirected input w/ initial command" {
            $si = NewProcessStartInfo "-noprofile -noexit ""`$function:prompt = { 'PS> ' }""" -RedirectStdIn
            $process = RunPowerShell $si
            $process.StandardInput.Write("1+1`n")
            $process.StandardOutput.ReadLine() | Should Be "PS> 1+1"
            $process.StandardOutput.ReadLine() | Should Be "2"
            $process.StandardInput.Write("1+2`n")
            $process.StandardOutput.ReadLine() | Should Be "PS> 1+2"
            $process.StandardOutput.ReadLine() | Should Be "3"
            $process.StandardInput.Close()
            $process.StandardOutput.ReadToEnd() | Should Be "PS> "
            EnsureChildHasExited $process
        }

        It "Redirected input explicit prompting (-File -)" {
            $si = NewProcessStartInfo "-noprofile -File -" -RedirectStdIn
            $process = RunPowerShell $si
            $process.StandardInput.Write("`$function:prompt = { 'PS> ' }`n")
            $null = $process.StandardOutput.ReadLine()
            $process.StandardInput.Write("1+1`n")
            $process.StandardOutput.ReadLine() | Should Be "PS> 1+1"
            $process.StandardOutput.ReadLine() | Should Be "2"
            $process.StandardInput.Close()
            $process.StandardOutput.ReadToEnd() | Should Be "PS> "
            EnsureChildHasExited $process
        }

        It "Redirected input no prompting (-Command -)" {
            $si = NewProcessStartInfo "-noprofile -" -RedirectStdIn
            $process = RunPowerShell $si
            $process.StandardInput.Write("1+1`n")
            $process.StandardOutput.ReadLine() | Should Be "2"

            # Multi-line input
            $process.StandardInput.Write("if (1)`n{`n    42`n}`n`n")
            $process.StandardOutput.ReadLine() | Should Be "42"
            $process.StandardInput.Write(@"
function foo
{
    'in foo'
}

foo

"@)
            $process.StandardOutput.ReadLine() | Should Be "in foo"

            # Backspace sent through stdin should be in the final string
            $process.StandardInput.Write("`"a`bc`".Length`n")
            $process.StandardOutput.ReadLine() | Should Be "3"

            # Last command with no newline - should be accepted and
            # produce output after closing stdin.
            $process.StandardInput.Write('22 + 22')
            $process.StandardInput.Close()
            $process.StandardOutput.ReadLine() | Should Be "44"

            EnsureChildHasExited $process
        }

        It "Redirected input w/ nested prompt" {
            $si = NewProcessStartInfo "-noprofile -noexit ""`$function:prompt = { 'PS' + ('>'*(`$nestedPromptLevel+1)) + ' ' }""" -RedirectStdIn
            $process = RunPowerShell $si
            $process.StandardInput.Write("`$host.EnterNestedPrompt()`n")
            $process.StandardOutput.ReadLine() | Should Be "PS> `$host.EnterNestedPrompt()"
            $process.StandardInput.Write("exit`n")
            $process.StandardOutput.ReadLine() | Should Be "PS>> exit"
            $process.StandardInput.Close()
            $process.StandardOutput.ReadToEnd() | Should Be "PS> "
            EnsureChildHasExited $process
        }
    }

    Context "Exception handling" {
        It "Should handle a CallDepthOverflow" {
            # Infinite recursion
            function recurse
            {
                recurse $args
            }

            try
            {
                recurse "args"
                Throw "Incorrect exception"
            }
            catch
            {
                $_.FullyQualifiedErrorId | Should Be "CallDepthOverflow"
            }
        }
    }
}

Describe "Console host api tests" -Tag CI {
    Context "String escape sequences" {
        $esc = [char]0x1b
        $testCases = 
            @{InputObject = "abc"; Length = 3; Name = "No escapes"},
            @{InputObject = "${esc} [31mabc"; Length = 9; Name = "Malformed escape - extra space"},
            @{InputObject = "${esc}abc"; Length = 4; Name = "Malformed escape - no csi"},
            @{InputObject = "[31mabc"; Length = 7; Name = "Malformed escape - no escape"}

        $testCases += if ($host.UI.SupportsVirtualTerminal)
        {
            @{InputObject = "$esc[31mabc"; Length = 3; Name = "Escape at start"}
            @{InputObject = "$esc[31mabc$esc[0m"; Length = 3; Name = "Escape at start and end"}
        }
        else
        {
            @{InputObject = "$esc[31mabc"; Length = 8; Name = "Escape at start - no virtual term support"}
            @{InputObject = "$esc[31mabc$esc[0m"; Length = 12; Name = "Escape at start and end - no virtual term support"}
        }

        It "Should properly calculate buffer cell width of '<Name>'" -TestCases $testCases {
            param($InputObject, $Length)
            $host.UI.RawUI.LengthInBufferCells($InputObject) | Should Be $Length
        }
    }
}