Custom Prompt Function for powershell

prompt.ps1

############################################################
# FUNCTION: Prompt                                         #
############################################################
# Redefine Prompt setting new color for new sessions       #
# and setting username, servername, PID and WS as title    #
# TODO: Customisable prompt            FIXED/              #
# TODO: Add Domain Information #D      DONE/               #
############################################################
function Prompt {
    <#
    .Description
    Customize your prompt s
    Supported Format
    #S
        Shell, ie PS
    #P
        Current Path
    #L
        Leaf of the current path
    #E
        Powershell classique end '>'
    #C
        Custom entry : 
            Display content set after :
            $Var => Standfor content of variable $Var
            &Var => Standfor content of scriptblock in $Var
            String string to display
        example #C:[ 
    #A
        $ if user ou # if admin
    #U
        USerName
    #M
        MachineName
    #I
        Process ID
    #V
        Powershell Version
    #W
        WorkingSet Size
    #G
        Git Status 
    ~Color 
        each TAG can be colorised by appending ~ColorNAme
    #>
    if (-not($Prompt)) {
        $LocalPrompt = "#S #P#E"
    } else {
        $LocalPrompt = $Prompt
    }
    $items = $LocalPrompt.split('#')
    $items | & { 
        process {
            if (-not($_)) {
    
            } elseif ($_ -match '([SPLECAUMIWDVG]):?([^~ ]*)~?([^ ]*)') {
    
                $splat = @{} 
                if ($matches[3]) {
                    $splat['ForegroundColor'] = $matches[3]
                }
                if ($matches[1] -eq 'S') {
                    $splat['Object'] = $_.Replace($matches[0], "PS")
                } elseif ($matches[1] -eq 'E') {
                    $splat['Object'] = $_.Replace($matches[0], ">")
                } elseif ($matches[1] -eq 'P') {
                    $splat['Object'] = $_.Replace($matches[0], (Get-Location).Path)
                } elseif ($matches[1] -eq 'C') {
                    if ($matches[2].StartsWith('$')) {
                        $var = Get-Variable -Name $matches[2].substring(1)
                        $splat['Object'] = $_.Replace($matches[0], $var )
                    } elseif ($matches[2].StartsWith('&') ) {
                        $var = & $(Get-Variable -Name $matches[2].substring(1)).Value
                        $splat['Object'] = $_.Replace($matches[0], $var )
                    } else {
                        $splat['Object'] = $_.Replace($matches[0], $matches[2])
                    }
                } elseif ($matches[1] -eq 'A') {
                    $elevated = ([Security.Principal.WindowsPrincipal][Security.Principal.WindowsIdentity]::GetCurrent()).IsInRole([Security.Principal.WindowsBuiltInRole]::Administrator)                    
                    if ($elevated) {
                        $splat['Object'] = $_.Replace($matches[0], '#')
                    } else {
                        $splat['Object'] = $_.Replace($matches[0], '$')
                    }
                } elseif ($matches[1] -eq 'U') {
                    $splat['Object'] = $_.Replace($matches[0], $env:username.trim())
                } elseif ($matches[1] -eq 'M') {
                    $splat['Object'] = $_.Replace($matches[0], $env:COMPUTERNAME.trim())
                } elseif ($matches[1] -eq 'I') {
                    $splat['Object'] = $_.Replace($matches[0], $PID)
                } elseif ($matches[1] -eq 'L') {
                    $splat['Object'] = $_.Replace($matches[0], $(Split-Path -Path  (Get-Location).Path -Leaf ))
                } elseif ($matches[1] -eq 'W') {
                    $splat['Object'] = $_.Replace($matches[0], $((Get-Process -pid $PID).WS / 1Mb))
                } elseif ($matches[1] -eq 'D') {
                    $splat['Object'] = $_.Replace($matches[0], $env:USERDOMAIN.Trim() )
                } elseif ($matches[1] -eq 'V') {
                    $splat['Object'] = $_.Replace($matches[0], $psversiontable.PSVersion.Major )
                } elseif ($matches[1] -eq 'G') {
                    $GitStatus = Get-GitStatus
                    $Branch = ""
                    if ($GitStatus) {
                        $Branch = " $($GitStatus.branch)"
                        if ($GitStatus.HasUntracked) {
                            $Branch += "*"
                        }
                        if ($GitStatus.AheadBy -gt 0 ) {
                            $Branch += ">$($GitStatus.AheadBy)"                            
                        } elseif ($GitStatus.BehindBy -gt 0) {
                            $Branch += "<$($GitStatus.BehindBy)"                            
                        }
                    }
                    $splat['Object'] = $_.Replace($matches[0], "$($Branch)" )
                }
                Write-Host -NoNewline @splat 
            }
    
        }
    }
    if ($Title) {
        $items = $Title.split('#')
        $items = $items | & { 
            process {
                if (-not($_)) {
    
                } elseif ($_ -match '([SPLECAUMIWDV]):?([^~ ]*)~?([^ ]*)') {
    
                    if ($matches[1] -eq 'S') {
                        $_.Replace($matches[0], "PowerShell")
                    } elseif ($matches[1] -eq 'E') {
                        $_.Replace($matches[0], ">")
                    } elseif ($matches[1] -eq 'P') {
                        $_.Replace($matches[0], (Get-Location).Path)
                    } elseif ($matches[1] -eq 'C') {
                        if ($matches[2].StartsWith('$')) {
                            $var = Get-Variable -Name $matches[2].substring(1)
                            $_.Replace($matches[0], $var )
                        } elseif ($matches[2].StartsWith('&') ) {
                            $var = & $(Get-Variable -Name $matches[2].substring(1)).Value
                            $_.Replace($matches[0], $var )
                        } else {
                            $_.Replace($matches[0], $matches[2])
                        }
                    } elseif ($matches[1] -eq 'A') {
                        $elevated = ([Security.Principal.WindowsPrincipal][Security.Principal.WindowsIdentity]::GetCurrent()).IsInRole([Security.Principal.WindowsBuiltInRole]::Administrator)                    
                        if ($elevated) {
                            $_.Replace($matches[0], '#')
                        } else {
                            $_.Replace($matches[0], '$')
                        }
                    } elseif ($matches[1] -eq 'U') {
                        $_.Replace($matches[0], $env:username.trim())
                    } elseif ($matches[1] -eq 'M') {
                        $_.Replace($matches[0], $env:COMPUTERNAME.trim())
                    } elseif ($matches[1] -eq 'I') {
                        $_.Replace($matches[0], $PID)
                    } elseif ($matches[1] -eq 'L') {
                        $_.Replace($matches[0], $(Split-Path -Path  (Get-Location).Path -Leaf ))
                    } elseif ($matches[1] -eq 'W') {
                        $_.Replace($matches[0], $((Get-Process -pid $PID).WS / 1Mb))
                    } elseif ($matches[1] -eq 'D') {
                        $_.replace($matches[1], $env:userdomain.trim())
                    } elseif ($matches[1] -eq 'V') {
                        $_.Replace($matches[0], $psversiontable.PSVersion.Major )
                    } elseif ($matches[1] -eq 'G') {
                        $GitStatus = Get-GitStatus
                        $Branch = ""
                        if ($GitStatus) {
                            $Branch = " $($GitStatus.branch)"
                            if ($GitStatus.HasUntracked) {
                                $Branch += "*"
                            }
                            if ($GitStatus.AheadBy -gt 0 ) {
                                $Branch += ">$($GitStatus.AheadBy)"                            
                            } elseif ($GitStatus.BehindBy -gt 0) {
                                $Branch += "<$($GitStatus.BehindBy)"                            
                            }
                        }
                    }
                }
            }
        }
        $host.ui.RawUI.WindowTitle = $items -join ''
    }
    Return " "
}