$PROFILE_PSReadLine.ps1

using namespace System.Management.Automation
using namespace System.Management.Automation.Language

if ($host.Name -eq 'ConsoleHost')
{
    Import-Module PSReadLine
}

Set-PSReadLineOption -PredictionSource History
Set-PSReadLineOption -PredictionViewStyle ListView
Set-PSReadLineOption -EditMode Windows

# 設定按下 Ctrl+d 可以退出 PowerShell 執行環境
Set-PSReadlineKeyHandler -Chord ctrl+d -Function ViExit

# 設定按下 Ctrl+w 可以刪除一個單字
Set-PSReadlineKeyHandler -Chord ctrl+w -Function BackwardDeleteWord

# 設定按下 Ctrl+e 可以移動游標到最後面(End)
Set-PSReadlineKeyHandler -Chord ctrl+e -Function EndOfLine

# 設定按下 Ctrl+a 可以移動游標到最前面(Begin)
Set-PSReadlineKeyHandler -Chord ctrl+a -Function BeginningOfLine

#Set-PSReadLineKeyHandler -Key UpArrow -Function HistorySearchBackward
#Set-PSReadLineKeyHandler -Key DownArrow -Function HistorySearchForward

# This key handler shows the entire or filtered history using Out-GridView. The
# typed text is used as the substring pattern for filtering. A selected command
# is inserted to the command line without invoking. Multiple command selection
# is supported, e.g. selected by Ctrl + Click.
Set-PSReadLineKeyHandler -Key F7 `
                         -BriefDescription History `
                         -LongDescription 'Show command history' `
                         -ScriptBlock {
    $pattern = $null
    [Microsoft.PowerShell.PSConsoleReadLine]::GetBufferState([ref]$pattern, [ref]$null)
    if ($pattern)
    {
        $pattern = [regex]::Escape($pattern)
    }

    $history = [System.Collections.ArrayList]@(
        $last = ''
        $lines = ''
        foreach ($line in [System.IO.File]::ReadLines((Get-PSReadLineOption).HistorySavePath))
        {
            if ($line.EndsWith('`'))
            {
                $line = $line.Substring(0, $line.Length - 1)
                $lines = if ($lines)
                {
                    "$lines`n$line"
                }
                else
                {
                    $line
                }
                continue
            }

            if ($lines)
            {
                $line = "$lines`n$line"
                $lines = ''
            }

            if (($line -cne $last) -and (!$pattern -or ($line -match $pattern)))
            {
                $last = $line
                $line
            }
        }
    )
    $history.Reverse()

    $command = $history | Out-GridView -Title History -PassThru
    if ($command)
    {
        [Microsoft.PowerShell.PSConsoleReadLine]::RevertLine()
        [Microsoft.PowerShell.PSConsoleReadLine]::Insert(($command -join "`n"))
    }
}


# F1 for help on the command line - naturally
Set-PSReadLineKeyHandler -Key F1 `
                         -BriefDescription CommandHelp `
                         -LongDescription "Open the help window for the current command" `
                         -ScriptBlock {
    param($key, $arg)

    $ast = $null
    $tokens = $null
    $errors = $null
    $cursor = $null
    [Microsoft.PowerShell.PSConsoleReadLine]::GetBufferState([ref]$ast, [ref]$tokens, [ref]$errors, [ref]$cursor)

    $commandAst = $ast.FindAll( {
        $node = $args[0]
        $node -is [CommandAst] -and
            $node.Extent.StartOffset -le $cursor -and
            $node.Extent.EndOffset -ge $cursor
        }, $true) | Select-Object -Last 1

    if ($commandAst -ne $null)
    {
        $commandName = $commandAst.GetCommandName()
        if ($commandName -ne $null)
        {
            $command = $ExecutionContext.InvokeCommand.GetCommand($commandName, 'All')
            if ($command -is [AliasInfo])
            {
                $commandName = $command.ResolvedCommandName
            }

            if ($commandName -ne $null)
            {
                Get-Help $commandName -ShowWindow
            }
        }
    }
}

Set-PSReadLineKeyHandler -Key '"',"'" `
                         -BriefDescription SmartInsertQuote `
                         -LongDescription "Insert paired quotes if not already on a quote" `
                         -ScriptBlock {
    param($key, $arg)

    $quote = $key.KeyChar

    $selectionStart = $null
    $selectionLength = $null
    [Microsoft.PowerShell.PSConsoleReadLine]::GetSelectionState([ref]$selectionStart, [ref]$selectionLength)

    $line = $null
    $cursor = $null
    [Microsoft.PowerShell.PSConsoleReadLine]::GetBufferState([ref]$line, [ref]$cursor)

    # If text is selected, just quote it without any smarts
    if ($selectionStart -ne -1)
    {
        [Microsoft.PowerShell.PSConsoleReadLine]::Replace($selectionStart, $selectionLength, $quote + $line.SubString($selectionStart, $selectionLength) + $quote)
        [Microsoft.PowerShell.PSConsoleReadLine]::SetCursorPosition($selectionStart + $selectionLength + 2)
        return
    }

    $ast = $null
    $tokens = $null
    $parseErrors = $null
    [Microsoft.PowerShell.PSConsoleReadLine]::GetBufferState([ref]$ast, [ref]$tokens, [ref]$parseErrors, [ref]$null)

    function FindToken
    {
        param($tokens, $cursor)

        foreach ($token in $tokens)
        {
            if ($cursor -lt $token.Extent.StartOffset) { continue }
            if ($cursor -lt $token.Extent.EndOffset) {
                $result = $token
                $token = $token -as [StringExpandableToken]
                if ($token) {
                    $nested = FindToken $token.NestedTokens $cursor
                    if ($nested) { $result = $nested }
                }

                return $result
            }
        }
        return $null
    }

    $token = FindToken $tokens $cursor

    # If we're on or inside a **quoted** string token (so not generic), we need to be smarter
    if ($token -is [StringToken] -and $token.Kind -ne [TokenKind]::Generic) {
        # If we're at the start of the string, assume we're inserting a new string
        if ($token.Extent.StartOffset -eq $cursor) {
            [Microsoft.PowerShell.PSConsoleReadLine]::Insert("$quote$quote ")
            [Microsoft.PowerShell.PSConsoleReadLine]::SetCursorPosition($cursor + 1)
            return
        }

        # If we're at the end of the string, move over the closing quote if present.
        if ($token.Extent.EndOffset -eq ($cursor + 1) -and $line[$cursor] -eq $quote) {
            [Microsoft.PowerShell.PSConsoleReadLine]::SetCursorPosition($cursor + 1)
            return
        }
    }

    if ($null -eq $token -or
        $token.Kind -eq [TokenKind]::RParen -or $token.Kind -eq [TokenKind]::RCurly -or $token.Kind -eq [TokenKind]::RBracket) {
        if ($line[0..$cursor].Where{$_ -eq $quote}.Count % 2 -eq 1) {
            # Odd number of quotes before the cursor, insert a single quote
            [Microsoft.PowerShell.PSConsoleReadLine]::Insert($quote)
        }
        else {
            # Insert matching quotes, move cursor to be in between the quotes
            [Microsoft.PowerShell.PSConsoleReadLine]::Insert("$quote$quote")
            [Microsoft.PowerShell.PSConsoleReadLine]::SetCursorPosition($cursor + 1)
        }
        return
    }

    # If cursor is at the start of a token, enclose it in quotes.
    if ($token.Extent.StartOffset -eq $cursor) {
        if ($token.Kind -eq [TokenKind]::Generic -or $token.Kind -eq [TokenKind]::Identifier -or 
            $token.Kind -eq [TokenKind]::Variable -or $token.TokenFlags.hasFlag([TokenFlags]::Keyword)) {
            $end = $token.Extent.EndOffset
            $len = $end - $cursor
            [Microsoft.PowerShell.PSConsoleReadLine]::Replace($cursor, $len, $quote + $line.SubString($cursor, $len) + $quote)
            [Microsoft.PowerShell.PSConsoleReadLine]::SetCursorPosition($end + 2)
            return
        }
    }

    # We failed to be smart, so just insert a single quote
    [Microsoft.PowerShell.PSConsoleReadLine]::Insert($quote)
}

Set-PSReadLineKeyHandler -Key '(','{','[' `
                         -BriefDescription InsertPairedBraces `
                         -LongDescription "Insert matching braces" `
                         -ScriptBlock {
    param($key, $arg)

    $closeChar = switch ($key.KeyChar)
    {
        <#case#> '(' { [char]')'; break }
        <#case#> '{' { [char]'}'; break }
        <#case#> '[' { [char]']'; break }
    }

    $selectionStart = $null
    $selectionLength = $null
    [Microsoft.PowerShell.PSConsoleReadLine]::GetSelectionState([ref]$selectionStart, [ref]$selectionLength)

    $line = $null
    $cursor = $null
    [Microsoft.PowerShell.PSConsoleReadLine]::GetBufferState([ref]$line, [ref]$cursor)
    
    if ($selectionStart -ne -1)
    {
      # Text is selected, wrap it in brackets
      [Microsoft.PowerShell.PSConsoleReadLine]::Replace($selectionStart, $selectionLength, $key.KeyChar + $line.SubString($selectionStart, $selectionLength) + $closeChar)
      [Microsoft.PowerShell.PSConsoleReadLine]::SetCursorPosition($selectionStart + $selectionLength + 2)
    } else {
      # No text is selected, insert a pair
      [Microsoft.PowerShell.PSConsoleReadLine]::Insert("$($key.KeyChar)$closeChar")
      [Microsoft.PowerShell.PSConsoleReadLine]::SetCursorPosition($cursor + 1)
    }
}

Set-PSReadLineKeyHandler -Key ')',']','}' `
                         -BriefDescription SmartCloseBraces `
                         -LongDescription "Insert closing brace or skip" `
                         -ScriptBlock {
    param($key, $arg)

    $line = $null
    $cursor = $null
    [Microsoft.PowerShell.PSConsoleReadLine]::GetBufferState([ref]$line, [ref]$cursor)

    if ($line[$cursor] -eq $key.KeyChar)
    {
        [Microsoft.PowerShell.PSConsoleReadLine]::SetCursorPosition($cursor + 1)
    }
    else
    {
        [Microsoft.PowerShell.PSConsoleReadLine]::Insert("$($key.KeyChar)")
    }
}

Set-PSReadLineKeyHandler -Key Backspace `
                         -BriefDescription SmartBackspace `
                         -LongDescription "Delete previous character or matching quotes/parens/braces" `
                         -ScriptBlock {
    param($key, $arg)

    $line = $null
    $cursor = $null
    [Microsoft.PowerShell.PSConsoleReadLine]::GetBufferState([ref]$line, [ref]$cursor)

    if ($cursor -gt 0)
    {
        $toMatch = $null
        if ($cursor -lt $line.Length)
        {
            switch ($line[$cursor])
            {
                <#case#> '"' { $toMatch = '"'; break }
                <#case#> "'" { $toMatch = "'"; break }
                <#case#> ')' { $toMatch = '('; break }
                <#case#> ']' { $toMatch = '['; break }
                <#case#> '}' { $toMatch = '{'; break }
            }
        }

        if ($toMatch -ne $null -and $line[$cursor-1] -eq $toMatch)
        {
            [Microsoft.PowerShell.PSConsoleReadLine]::Delete($cursor - 1, 2)
        }
        else
        {
            [Microsoft.PowerShell.PSConsoleReadLine]::BackwardDeleteChar($key, $arg)
        }
    }
}