. $PSScriptRoot\..\..\Load-PesterModules.ps1
$here = Split-Path -Parent $MyInvocation.MyCommand.Path
$sut = (Split-Path -Leaf $MyInvocation.MyCommand.Path) -replace '\.tests\.', '.'
$functionPath = Join-Path -Path $here -ChildPath $sut
Write-Host "Overriding SUT: $functionPath"
Import-Module $functionPath -Force
$moduleForMock = ""

Describe "Get-CurrentInstanceAvailabilityZone" {

    Context "When Not Running in AWS" {

        Mock -ModuleName $moduleForMock Test-IsAws { return $false }
        Mock -ModuleName $moduleForMock Write-Warning {}
        Mock -ModuleName $moduleForMock Get-InstanceMetadata {}

        Get-CurrentInstanceAvailabilityZone -WarningAction SilentlyContinue

        It "Calls Test-IsAws" {

            Assert-MockCalled -ModuleName $moduleForMock Test-IsAws -Times 1 -Exactly -Scope Context
        }

        It "Writes a Warning" {

            Assert-MockCalled -ModuleName $moduleForMock Write-Warning -Times 1 -Exactly -Scope Context
        }

        It "Returns Without Calling AWS APIs" {

            Assert-MockCalled -ModuleName $moduleForMock Get-InstanceMetadata -ParameterFilter {$Endpoint -Match $azEndpointPath } -Times 0 -Exactly -Scope Context
        }
    }

    Context "When Running in AWS" {

        $azEndpointPath = "meta-data/placement/availability-zone"
        Mock -ModuleName $moduleForMock Test-IsAws { return $true }
        Mock -ModuleName $moduleForMock Write-Warning {}
        Mock -ModuleName $moduleForMock Get-InstanceMetadata {

            return (New-Object PSObject -Property @{
                    "StatusCode" = "200";
                    "Content" = "us-fake-1a";
                } )
        }

        It "Returns the Instance AvailabilityZone" {

            $testResult = Get-CurrentInstanceAvailabilityZone
            Assert-MockCalled -ModuleName $moduleForMock Get-InstanceMetadata -ParameterFilter {$Endpoint -Match $azEndpointPath } -Times 1 -Exactly -Scope It

            $testResult | Should -Be "us-fake-1a"
        }

        It "Throws if not success" {
            Mock -ModuleName $moduleForMock Get-InstanceMetadata {
                return (New-Object PSObject -Property @{
                    "StatusCode" = "404";
                    "Content" = "Not found";
                } )
            }

            {Get-CurrentInstanceAvailabilityZone} | Should -Throw
        }
    }
}