Gumby.Path.psm1

<#
.SYNOPSIS
Normalizes a path.
 
.PARAMETER Path
Path to normalize.
 
.OUTPUTS
Normalized path.
#>

function PathNormalize([string] $Path) {
    return $path.Replace('/', '\')
}

<#
.SYNOPSIS
Gets the path separator character for platform the function is running on.
 
.OUTPUTS
Path separator.
#>

function PathSeparator() { return '\' }

<#
.SYNOPSIS
Gets a list of common path separator characters.
 
.OUTPUTS
List of common path separator characters.
#>

function PathSeparators() { return '/', '\' }

<#
.SYNOPSIS
Extracts the base name part of a file path.
 
.PARAMETER Path
Path to extract base name part from.
 
.OUTPUTS
Base name part.
#>

function PathFileBaseName([string] $Path) {

    # a: Position after the last separator (if any)
    # b: Position of the last dot (if any)

    # "p"
    # 0
    # a
    # b

    # "p.q"
    # 012
    # a
    # b

    # "p.q.r"
    # 01234
    # a
    # b

    # "p\q"
    # 012
    # a
    # b

    # "p.q\r"
    # 01234
    # a
    # b

    # "p\q.r\s.t.u"
    # 01234567890
    # a
    # b

    [int] $a = $Path.LastIndexOf((PathSeparator))

    if ($a -lt 0) { $a = 0 } else { ++$a }

    if ($a -ge $Path.Length) { return "" }

    [int] $b = $Path.LastIndexOf('.')

    if ($b -lt $a) {
        return $Path.Substring($a)
    } else {
        return $Path.Substring($a, $b - $a)
    }
}

<#
.SYNOPSIS
Joins file name parts into a path.
 
.PARAMETER Directories
Directory parts.
 
.PARAMETER BaseName
Base name part.
 
.PARAMETER Extension
Extension part.
 
.OUTPUTS
Joined path.
#>

function PathJoin([string[]]$Directories, [string] $BaseName, [string] $Extension) {
    $sb = [Text.StringBuilder]::new()

    foreach ($dir in $Directories) {
        $sb.Append($dir.Trim((PathSeparators))).Append((PathSeparator)) | Out-Null
    }

    $sb.Append($BaseName) | Out-Null

    if (![string]::IsNullOrEmpty($Extension)) {
        if ($Extension.StartsWith('.')) {
            $sb.Append($Extension) | Out-Null
        } else {
            $sb.Append('.').Append($Extension) | Out-Null
        }
    }

    return $sb.ToString()
}

function PathAsUri($Path) {
    return "file:$($Path.Replace('\', '/'))"
}