# Copyright 2012 Aaron Jensen
# 
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
# 
#     http://www.apache.org/licenses/LICENSE-2.0
# 
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

function Get-PathProvider
{
    <#
    .SYNOPSIS
    Returns a path's PowerShell provider.

    .DESCRIPTION
    When you want to do something with a path that depends on its provider, use this function.  The path doesn't have to exist.

    If you pass in a relative path, it is resolved relative to the current directory.  So make sure you're in the right place.

    .OUTPUTS
    System.Management.Automation.ProviderInfo.

    .EXAMPLE
    Get-PathProvider -Path 'C:\Windows'

    Demonstrates how to get the path provider for an NTFS path.
    #>
    [CmdletBinding()]
    param(
        [Parameter(Mandatory=$true)]
        [string]
        # The path whose provider to get.
        $Path
    )

    Set-StrictMode -Version 'Latest'

    $pathQualifier = Split-Path -Qualifier $Path -ErrorAction SilentlyContinue
    if( -not $pathQualifier )
    {
        $Path = Join-Path -Path (Get-Location) -ChildPath $Path
        $pathQualifier = Split-Path -Qualifier $Path -ErrorAction SilentlyContinue
        if( -not $pathQualifier )
        {
            Write-Error "Qualifier for path '$Path' not found."
            return
        }
    }
    Get-PSDrive $pathQualifier.Trim(':') |
        Select-Object -ExpandProperty 'Provider'

}