# Copyright (c) Microsoft Corporation. All rights reserved.
# Licensed under the MIT License.
function Wait-UntilTrue
{
    [CmdletBinding()]
    param (
        [ScriptBlock]$sb,
        [int]$TimeoutInMilliseconds = 10000,
        [int]$IntervalInMilliseconds = 1000
        )
    # Get the current time
    $startTime = [DateTime]::Now

    # Loop until the script block evaluates to true
    while (-not ($sb.Invoke())) {
        # If the timeout period has passed, return false
        if (([DateTime]::Now - $startTime).TotalMilliseconds -gt $timeoutInMilliseconds) {
            return $false
        }
        # Sleep for the specified interval
        Start-Sleep -Milliseconds $intervalInMilliseconds
    }
    return $true
}

function Wait-FileToBePresent
{
    [CmdletBinding()]
    param (
        [string]$File,
        [int]$TimeoutInSeconds = 10,
        [int]$IntervalInMilliseconds = 100
    )

    Wait-UntilTrue -sb { Test-Path $File } -TimeoutInMilliseconds ($TimeoutInSeconds*1000) -IntervalInMilliseconds $IntervalInMilliseconds > $null
}

function Test-IsElevated
{
    $IsElevated = $False
    if ( $IsWindows ) {
        # on Windows we can determine whether we're executing in an
        # elevated context
        $identity = [System.Security.Principal.WindowsIdentity]::GetCurrent()
        $windowsPrincipal = new-object 'Security.Principal.WindowsPrincipal' $identity
        if ($windowsPrincipal.IsInRole("Administrators") -eq 1)
        {
            $IsElevated = $true
        }
    }
    else {
        # on Linux, tests run via sudo will generally report "root" for whoami
        if ( (whoami) -match "root" ) {
            $IsElevated = $true
        }
    }
    return $IsElevated
}
#This function follows the pester naming convention
function ShouldBeErrorId
{
    param([Parameter(ValueFromPipeline, Mandatory)]
        [ScriptBlock]
        $sb,

        [Parameter(Mandatory, Position=0)]
        [string]
        $FullyQualifiedErrorId)

        try
        {
            & $sb | Out-Null
            Throw "No Exception!"
        }
        catch
        {
            $_.FullyQualifiedErrorId | Should Be $FullyQualifiedErrorId | Out-Null
            # Write the exception to output that allow us to check later other properies of the exception
            Write-Output $_
        }
}

function Get-RandomFileName
{
    [System.IO.Path]::GetFileNameWithoutExtension([IO.Path]::GetRandomFileName())
}

#
# Testhook setting functions
# note these manipulate private data in the PowerShell engine which will
# enable us to not actually alter the system or mock returned data
#
$SCRIPT:TesthookType = [system.management.automation.internal.internaltesthooks] 
function Test-TesthookIsSet
{
    param (
        [ValidateNotNullOrEmpty()]
        [Parameter(Mandatory=$true)]
        $testhookName
    )
    try {
        return ${Script:TesthookType}.GetField($testhookName, "NonPublic,Static").GetValue($null)
    }
    catch {
        # fall through
    }
    return $false
}

function Enable-Testhook
{
    param (
        [ValidateNotNullOrEmpty()]
        [Parameter(Mandatory=$true)]
        $testhookName
    )
    ${Script:TesthookType}::SetTestHook($testhookName, $true)
}

function Disable-Testhook
{
    param (
        [ValidateNotNullOrEmpty()]
        [Parameter(Mandatory=$true)]
        $testhookName
    )
    ${Script:TesthookType}::SetTestHook($testhookName, $false)
}

function Set-TesthookResult
{
    param (
        [ValidateNotNullOrEmpty()]
        [Parameter(Mandatory=$true)]
        $testhookName, 
        [ValidateNotNullOrEmpty()]
        [Parameter(Mandatory=$true)]
        $value
    )
    ${Script:TesthookType}::SetTestHook($testhookName, $value)
}